what is limitation of study in research work

How to Write Limitations of the Study (with examples)

This blog emphasizes the importance of recognizing and effectively writing about limitations in research. It discusses the types of limitations, their significance, and provides guidelines for writing about them, highlighting their role in advancing scholarly research.

Updated on August 24, 2023

No matter how well thought out, every research endeavor encounters challenges. There is simply no way to predict all possible variances throughout the process.

These uncharted boundaries and abrupt constraints are known as limitations in research . Identifying and acknowledging limitations is crucial for conducting rigorous studies. Limitations provide context and shed light on gaps in the prevailing inquiry and literature.

This article explores the importance of recognizing limitations and discusses how to write them effectively. By interpreting limitations in research and considering prevalent examples, we aim to reframe the perception from shameful mistakes to respectable revelations.

What are limitations in research?

In the clearest terms, research limitations are the practical or theoretical shortcomings of a study that are often outside of the researcher’s control . While these weaknesses limit the generalizability of a study’s conclusions, they also present a foundation for future research.

Sometimes limitations arise from tangible circumstances like time and funding constraints, or equipment and participant availability. Other times the rationale is more obscure and buried within the research design. Common types of limitations and their ramifications include:

• Theoretical: limits the scope, depth, or applicability of a study.
• Methodological: limits the quality, quantity, or diversity of the data.
• Empirical: limits the representativeness, validity, or reliability of the data.
• Analytical: limits the accuracy, completeness, or significance of the findings.
• Ethical: limits the access, consent, or confidentiality of the data.

Regardless of how, when, or why they arise, limitations are a natural part of the research process and should never be ignored . Like all other aspects, they are vital in their own purpose.

Why is identifying limitations important?

Whether to seek acceptance or avoid struggle, humans often instinctively hide flaws and mistakes. Merging this thought process into research by attempting to hide limitations, however, is a bad idea. It has the potential to negate the validity of outcomes and damage the reputation of scholars.

By identifying and addressing limitations throughout a project, researchers strengthen their arguments and curtail the chance of peer censure based on overlooked mistakes. Pointing out these flaws shows an understanding of variable limits and a scrupulous research process.

Showing awareness of and taking responsibility for a project’s boundaries and challenges validates the integrity and transparency of a researcher. It further demonstrates the researchers understand the applicable literature and have thoroughly evaluated their chosen research methods.

Presenting limitations also benefits the readers by providing context for research findings. It guides them to interpret the project’s conclusions only within the scope of very specific conditions. By allowing for an appropriate generalization of the findings that is accurately confined by research boundaries and is not too broad, limitations boost a study’s credibility .

Limitations are true assets to the research process. They highlight opportunities for future research. When researchers identify the limitations of their particular approach to a study question, they enable precise transferability and improve chances for reproducibility. 

Simply stating a project’s limitations is not adequate for spurring further research, though. To spark the interest of other researchers, these acknowledgements must come with thorough explanations regarding how the limitations affected the current study and how they can potentially be overcome with amended methods.

How to write limitations

Typically, the information about a study’s limitations is situated either at the beginning of the discussion section to provide context for readers or at the conclusion of the discussion section to acknowledge the need for further research. However, it varies depending upon the target journal or publication guidelines. 

Don’t hide your limitations

It is also important to not bury a limitation in the body of the paper unless it has a unique connection to a topic in that section. If so, it needs to be reiterated with the other limitations or at the conclusion of the discussion section. Wherever it is included in the manuscript, ensure that the limitations section is prominently positioned and clearly introduced.

While maintaining transparency by disclosing limitations means taking a comprehensive approach, it is not necessary to discuss everything that could have potentially gone wrong during the research study. If there is no commitment to investigation in the introduction, it is unnecessary to consider the issue a limitation to the research. Wholly consider the term ‘limitations’ and ask, “Did it significantly change or limit the possible outcomes?” Then, qualify the occurrence as either a limitation to include in the current manuscript or as an idea to note for other projects. 

Writing limitations

Once the limitations are concretely identified and it is decided where they will be included in the paper, researchers are ready for the writing task. Including only what is pertinent, keeping explanations detailed but concise, and employing the following guidelines is key for crafting valuable limitations:

1) Identify and describe the limitations : Clearly introduce the limitation by classifying its form and specifying its origin. For example:

• An unintentional bias encountered during data collection
• An intentional use of unplanned post-hoc data analysis

2) Explain the implications : Describe how the limitation potentially influences the study’s findings and how the validity and generalizability are subsequently impacted. Provide examples and evidence to support claims of the limitations’ effects without making excuses or exaggerating their impact. Overall, be transparent and objective in presenting the limitations, without undermining the significance of the research. 

3) Provide alternative approaches for future studies : Offer specific suggestions for potential improvements or avenues for further investigation. Demonstrate a proactive approach by encouraging future research that addresses the identified gaps and, therefore, expands the knowledge base.

Whether presenting limitations as an individual section within the manuscript or as a subtopic in the discussion area, authors should use clear headings and straightforward language to facilitate readability. There is no need to complicate limitations with jargon, computations, or complex datasets.

Examples of common limitations

Limitations are generally grouped into two categories , methodology and research process .

Methodology limitations

Methodology may include limitations due to:

• Sample size
• Lack of available or reliable data
• Lack of prior research studies on the topic
• Measure used to collect the data
• Self-reported data

The researcher is addressing how the large sample size requires a reassessment of the measures used to collect and analyze the data.

Research process limitations

Limitations during the research process may arise from:

• Access to information
• Longitudinal effects
• Cultural and other biases
• Language fluency
• Time constraints

The author is pointing out that the model’s estimates are based on potentially biased observational studies.

Final thoughts

Successfully proving theories and touting great achievements are only two very narrow goals of scholarly research. The true passion and greatest efforts of researchers comes more in the form of confronting assumptions and exploring the obscure.

In many ways, recognizing and sharing the limitations of a research study both allows for and encourages this type of discovery that continuously pushes research forward. By using limitations to provide a transparent account of the project's boundaries and to contextualize the findings, researchers pave the way for even more robust and impactful research in the future.

Charla Viera, MS

See our "Privacy Policy"

Ensure your structure and ideas are consistent and clearly communicated

Pair your Premium Editing with our add-on service Presubmission Review for an overall assessment of your manuscript.

• USC Libraries
• Research Guides

Organizing Your Social Sciences Research Paper

• Limitations of the Study
• Purpose of Guide
• Design Flaws to Avoid
• Independent and Dependent Variables
• Glossary of Research Terms
• Reading Research Effectively
• Narrowing a Topic Idea
• Broadening a Topic Idea
• Extending the Timeliness of a Topic Idea
• Academic Writing Style
• Applying Critical Thinking
• Choosing a Title
• Making an Outline
• Paragraph Development
• Research Process Video Series
• Executive Summary
• The C.A.R.S. Model
• Background Information
• The Research Problem/Question
• Theoretical Framework
• Citation Tracking
• Content Alert Services
• Evaluating Sources
• Primary Sources
• Secondary Sources
• Tiertiary Sources
• Scholarly vs. Popular Publications
• Qualitative Methods
• Quantitative Methods
• Insiderness
• Using Non-Textual Elements
• Common Grammar Mistakes
• Writing Concisely
• Avoiding Plagiarism
• Footnotes or Endnotes?
• Further Readings
• Generative AI and Writing
• USC Libraries Tutorials and Other Guides
• Bibliography

The limitations of the study are those characteristics of design or methodology that impacted or influenced the interpretation of the findings from your research. Study limitations are the constraints placed on the ability to generalize from the results, to further describe applications to practice, and/or related to the utility of findings that are the result of the ways in which you initially chose to design the study or the method used to establish internal and external validity or the result of unanticipated challenges that emerged during the study.

Price, James H. and Judy Murnan. “Research Limitations and the Necessity of Reporting Them.” American Journal of Health Education 35 (2004): 66-67; Theofanidis, Dimitrios and Antigoni Fountouki. "Limitations and Delimitations in the Research Process." Perioperative Nursing 7 (September-December 2018): 155-163. .

Importance of...

Always acknowledge a study's limitations. It is far better that you identify and acknowledge your study’s limitations than to have them pointed out by your professor and have your grade lowered because you appeared to have ignored them or didn't realize they existed.

Keep in mind that acknowledgment of a study's limitations is an opportunity to make suggestions for further research. If you do connect your study's limitations to suggestions for further research, be sure to explain the ways in which these unanswered questions may become more focused because of your study.

Acknowledgment of a study's limitations also provides you with opportunities to demonstrate that you have thought critically about the research problem, understood the relevant literature published about it, and correctly assessed the methods chosen for studying the problem. A key objective of the research process is not only discovering new knowledge but also to confront assumptions and explore what we don't know.

Claiming limitations is a subjective process because you must evaluate the impact of those limitations . Don't just list key weaknesses and the magnitude of a study's limitations. To do so diminishes the validity of your research because it leaves the reader wondering whether, or in what ways, limitation(s) in your study may have impacted the results and conclusions. Limitations require a critical, overall appraisal and interpretation of their impact. You should answer the question: do these problems with errors, methods, validity, etc. eventually matter and, if so, to what extent?

Price, James H. and Judy Murnan. “Research Limitations and the Necessity of Reporting Them.” American Journal of Health Education 35 (2004): 66-67; Structure: How to Structure the Research Limitations Section of Your Dissertation. Dissertations and Theses: An Online Textbook. Laerd.com.

Descriptions of Possible Limitations

All studies have limitations . However, it is important that you restrict your discussion to limitations related to the research problem under investigation. For example, if a meta-analysis of existing literature is not a stated purpose of your research, it should not be discussed as a limitation. Do not apologize for not addressing issues that you did not promise to investigate in the introduction of your paper.

Here are examples of limitations related to methodology and the research process you may need to describe and discuss how they possibly impacted your results. Note that descriptions of limitations should be stated in the past tense because they were discovered after you completed your research.

Possible Methodological Limitations

• Sample size -- the number of the units of analysis you use in your study is dictated by the type of research problem you are investigating. Note that, if your sample size is too small, it will be difficult to find significant relationships from the data, as statistical tests normally require a larger sample size to ensure a representative distribution of the population and to be considered representative of groups of people to whom results will be generalized or transferred. Note that sample size is generally less relevant in qualitative research if explained in the context of the research problem.
• Lack of available and/or reliable data -- a lack of data or of reliable data will likely require you to limit the scope of your analysis, the size of your sample, or it can be a significant obstacle in finding a trend and a meaningful relationship. You need to not only describe these limitations but provide cogent reasons why you believe data is missing or is unreliable. However, don’t just throw up your hands in frustration; use this as an opportunity to describe a need for future research based on designing a different method for gathering data.
• Lack of prior research studies on the topic -- citing prior research studies forms the basis of your literature review and helps lay a foundation for understanding the research problem you are investigating. Depending on the currency or scope of your research topic, there may be little, if any, prior research on your topic. Before assuming this to be true, though, consult with a librarian! In cases when a librarian has confirmed that there is little or no prior research, you may be required to develop an entirely new research typology [for example, using an exploratory rather than an explanatory research design ]. Note again that discovering a limitation can serve as an important opportunity to identify new gaps in the literature and to describe the need for further research.
• Measure used to collect the data -- sometimes it is the case that, after completing your interpretation of the findings, you discover that the way in which you gathered data inhibited your ability to conduct a thorough analysis of the results. For example, you regret not including a specific question in a survey that, in retrospect, could have helped address a particular issue that emerged later in the study. Acknowledge the deficiency by stating a need for future researchers to revise the specific method for gathering data.
• Self-reported data -- whether you are relying on pre-existing data or you are conducting a qualitative research study and gathering the data yourself, self-reported data is limited by the fact that it rarely can be independently verified. In other words, you have to the accuracy of what people say, whether in interviews, focus groups, or on questionnaires, at face value. However, self-reported data can contain several potential sources of bias that you should be alert to and note as limitations. These biases become apparent if they are incongruent with data from other sources. These are: (1) selective memory [remembering or not remembering experiences or events that occurred at some point in the past]; (2) telescoping [recalling events that occurred at one time as if they occurred at another time]; (3) attribution [the act of attributing positive events and outcomes to one's own agency, but attributing negative events and outcomes to external forces]; and, (4) exaggeration [the act of representing outcomes or embellishing events as more significant than is actually suggested from other data].

Possible Limitations of the Researcher

• Access -- if your study depends on having access to people, organizations, data, or documents and, for whatever reason, access is denied or limited in some way, the reasons for this needs to be described. Also, include an explanation why being denied or limited access did not prevent you from following through on your study.
• Longitudinal effects -- unlike your professor, who can literally devote years [even a lifetime] to studying a single topic, the time available to investigate a research problem and to measure change or stability over time is constrained by the due date of your assignment. Be sure to choose a research problem that does not require an excessive amount of time to complete the literature review, apply the methodology, and gather and interpret the results. If you're unsure whether you can complete your research within the confines of the assignment's due date, talk to your professor.
• Cultural and other type of bias -- we all have biases, whether we are conscience of them or not. Bias is when a person, place, event, or thing is viewed or shown in a consistently inaccurate way. Bias is usually negative, though one can have a positive bias as well, especially if that bias reflects your reliance on research that only support your hypothesis. When proof-reading your paper, be especially critical in reviewing how you have stated a problem, selected the data to be studied, what may have been omitted, the manner in which you have ordered events, people, or places, how you have chosen to represent a person, place, or thing, to name a phenomenon, or to use possible words with a positive or negative connotation. NOTE :   If you detect bias in prior research, it must be acknowledged and you should explain what measures were taken to avoid perpetuating that bias. For example, if a previous study only used boys to examine how music education supports effective math skills, describe how your research expands the study to include girls.
• Fluency in a language -- if your research focuses , for example, on measuring the perceived value of after-school tutoring among Mexican-American ESL [English as a Second Language] students and you are not fluent in Spanish, you are limited in being able to read and interpret Spanish language research studies on the topic or to speak with these students in their primary language. This deficiency should be acknowledged.

Aguinis, Hermam and Jeffrey R. Edwards. “Methodological Wishes for the Next Decade and How to Make Wishes Come True.” Journal of Management Studies 51 (January 2014): 143-174; Brutus, Stéphane et al. "Self-Reported Limitations and Future Directions in Scholarly Reports: Analysis and Recommendations." Journal of Management 39 (January 2013): 48-75; Senunyeme, Emmanuel K. Business Research Methods. Powerpoint Presentation. Regent University of Science and Technology; ter Riet, Gerben et al. “All That Glitters Isn't Gold: A Survey on Acknowledgment of Limitations in Biomedical Studies.” PLOS One 8 (November 2013): 1-6.

Structure and Writing Style

Information about the limitations of your study are generally placed either at the beginning of the discussion section of your paper so the reader knows and understands the limitations before reading the rest of your analysis of the findings, or, the limitations are outlined at the conclusion of the discussion section as an acknowledgement of the need for further study. Statements about a study's limitations should not be buried in the body [middle] of the discussion section unless a limitation is specific to something covered in that part of the paper. If this is the case, though, the limitation should be reiterated at the conclusion of the section.

If you determine that your study is seriously flawed due to important limitations , such as, an inability to acquire critical data, consider reframing it as an exploratory study intended to lay the groundwork for a more complete research study in the future. Be sure, though, to specifically explain the ways that these flaws can be successfully overcome in a new study.

But, do not use this as an excuse for not developing a thorough research paper! Review the tab in this guide for developing a research topic . If serious limitations exist, it generally indicates a likelihood that your research problem is too narrowly defined or that the issue or event under study is too recent and, thus, very little research has been written about it. If serious limitations do emerge, consult with your professor about possible ways to overcome them or how to revise your study.

When discussing the limitations of your research, be sure to:

• Describe each limitation in detailed but concise terms;
• Explain why each limitation exists;
• Provide the reasons why each limitation could not be overcome using the method(s) chosen to acquire or gather the data [cite to other studies that had similar problems when possible];
• Assess the impact of each limitation in relation to the overall findings and conclusions of your study; and,
• If appropriate, describe how these limitations could point to the need for further research.

Remember that the method you chose may be the source of a significant limitation that has emerged during your interpretation of the results [for example, you didn't interview a group of people that you later wish you had]. If this is the case, don't panic. Acknowledge it, and explain how applying a different or more robust methodology might address the research problem more effectively in a future study. A underlying goal of scholarly research is not only to show what works, but to demonstrate what doesn't work or what needs further clarification.

Aguinis, Hermam and Jeffrey R. Edwards. “Methodological Wishes for the Next Decade and How to Make Wishes Come True.” Journal of Management Studies 51 (January 2014): 143-174; Brutus, Stéphane et al. "Self-Reported Limitations and Future Directions in Scholarly Reports: Analysis and Recommendations." Journal of Management 39 (January 2013): 48-75; Ioannidis, John P.A. "Limitations are not Properly Acknowledged in the Scientific Literature." Journal of Clinical Epidemiology 60 (2007): 324-329; Pasek, Josh. Writing the Empirical Social Science Research Paper: A Guide for the Perplexed. January 24, 2012. Academia.edu; Structure: How to Structure the Research Limitations Section of Your Dissertation. Dissertations and Theses: An Online Textbook. Laerd.com; What Is an Academic Paper? Institute for Writing Rhetoric. Dartmouth College; Writing the Experimental Report: Methods, Results, and Discussion. The Writing Lab and The OWL. Purdue University.

Writing Tip

Don't Inflate the Importance of Your Findings!

After all the hard work and long hours devoted to writing your research paper, it is easy to get carried away with attributing unwarranted importance to what you’ve done. We all want our academic work to be viewed as excellent and worthy of a good grade, but it is important that you understand and openly acknowledge the limitations of your study. Inflating the importance of your study's findings could be perceived by your readers as an attempt hide its flaws or encourage a biased interpretation of the results. A small measure of humility goes a long way!

Another Writing Tip

Negative Results are Not a Limitation!

Negative evidence refers to findings that unexpectedly challenge rather than support your hypothesis. If you didn't get the results you anticipated, it may mean your hypothesis was incorrect and needs to be reformulated. Or, perhaps you have stumbled onto something unexpected that warrants further study. Moreover, the absence of an effect may be very telling in many situations, particularly in experimental research designs. In any case, your results may very well be of importance to others even though they did not support your hypothesis. Do not fall into the trap of thinking that results contrary to what you expected is a limitation to your study. If you carried out the research well, they are simply your results and only require additional interpretation.

Lewis, George H. and Jonathan F. Lewis. “The Dog in the Night-Time: Negative Evidence in Social Research.” The British Journal of Sociology 31 (December 1980): 544-558.

Yet Another Writing Tip

Sample Size Limitations in Qualitative Research

Sample sizes are typically smaller in qualitative research because, as the study goes on, acquiring more data does not necessarily lead to more information. This is because one occurrence of a piece of data, or a code, is all that is necessary to ensure that it becomes part of the analysis framework. However, it remains true that sample sizes that are too small cannot adequately support claims of having achieved valid conclusions and sample sizes that are too large do not permit the deep, naturalistic, and inductive analysis that defines qualitative inquiry. Determining adequate sample size in qualitative research is ultimately a matter of judgment and experience in evaluating the quality of the information collected against the uses to which it will be applied and the particular research method and purposeful sampling strategy employed. If the sample size is found to be a limitation, it may reflect your judgment about the methodological technique chosen [e.g., single life history study versus focus group interviews] rather than the number of respondents used.

Boddy, Clive Roland. "Sample Size for Qualitative Research." Qualitative Market Research: An International Journal 19 (2016): 426-432; Huberman, A. Michael and Matthew B. Miles. "Data Management and Analysis Methods." In Handbook of Qualitative Research . Norman K. Denzin and Yvonna S. Lincoln, eds. (Thousand Oaks, CA: Sage, 1994), pp. 428-444; Blaikie, Norman. "Confounding Issues Related to Determining Sample Size in Qualitative Research." International Journal of Social Research Methodology 21 (2018): 635-641; Oppong, Steward Harrison. "The Problem of Sampling in qualitative Research." Asian Journal of Management Sciences and Education 2 (2013): 202-210.

• << Previous: 8. The Discussion
• Next: 9. The Conclusion >>
• Last Updated: May 9, 2024 11:05 AM
• URL: https://libguides.usc.edu/writingguide

How to present limitations in research

Last updated

30 January 2024

Reviewed by

Limitations don’t invalidate or diminish your results, but it’s best to acknowledge them. This will enable you to address any questions your study failed to answer because of them.

In this guide, learn how to recognize, present, and overcome limitations in research.

• What is a research limitation?

Research limitations are weaknesses in your research design or execution that may have impacted outcomes and conclusions. Uncovering limitations doesn’t necessarily indicate poor research design—it just means you encountered challenges you couldn’t have anticipated that limited your research efforts.

Does basic research have limitations?

Basic research aims to provide more information about your research topic. It requires the same standard research methodology and data collection efforts as any other research type, and it can also have limitations.

• Common research limitations

Researchers encounter common limitations when embarking on a study. Limitations can occur in relation to the methods you apply or the research process you design. They could also be connected to you as the researcher.

Methodology limitations

Not having access to data or reliable information can impact the methods used to facilitate your research. A lack of data or reliability may limit the parameters of your study area and the extent of your exploration.

Your sample size may also be affected because you won’t have any direction on how big or small it should be and who or what you should include. Having too few participants won’t adequately represent the population or groups of people needed to draw meaningful conclusions.

Research process limitations

The study’s design can impose constraints on the process. For example, as you’re conducting the research, issues may arise that don’t conform to the data collection methodology you developed. You may not realize until well into the process that you should have incorporated more specific questions or comprehensive experiments to generate the data you need to have confidence in your results.

Constraints on resources can also have an impact. Being limited on participants or participation incentives may limit your sample sizes. Insufficient tools, equipment, and materials to conduct a thorough study may also be a factor.

Common researcher limitations

Here are some of the common researcher limitations you may encounter:

Time: some research areas require multi-year longitudinal approaches, but you might not be able to dedicate that much time. Imagine you want to measure how much memory a person loses as they age. This may involve conducting multiple tests on a sample of participants over 20–30 years, which may be impossible.

Bias: researchers can consciously or unconsciously apply bias to their research. Biases can contribute to relying on research sources and methodologies that will only support your beliefs about the research you’re embarking on. You might also omit relevant issues or participants from the scope of your study because of your biases.

Limited access to data : you may need to pay to access specific databases or journals that would be helpful to your research process. You might also need to gain information from certain people or organizations but have limited access to them. These cases require readjusting your process and explaining why your findings are still reliable.

• Why is it important to identify limitations?

Identifying limitations adds credibility to research and provides a deeper understanding of how you arrived at your conclusions.

Constraints may have prevented you from collecting specific data or information you hoped would prove or disprove your hypothesis or provide a more comprehensive understanding of your research topic.

However, identifying the limitations contributing to your conclusions can inspire further research efforts that help gather more substantial information and data.

• Where to put limitations in a research paper

A research paper is broken up into different sections that appear in the following order:

Introduction

Methodology

The discussion portion of your paper explores your findings and puts them in the context of the overall research. Either place research limitations at the beginning of the discussion section before the analysis of your findings or at the end of the section to indicate that further research needs to be pursued.

What not to include in the limitations section

Evidence that doesn’t support your hypothesis is not a limitation, so you shouldn’t include it in the limitation section. Don’t just list limitations and their degree of severity without further explanation.

• How to present limitations

You’ll want to present the limitations of your study in a way that doesn’t diminish the validity of your research and leave the reader wondering if your results and conclusions have been compromised.

Include only the limitations that directly relate to and impact how you addressed your research questions. Following a specific format enables the reader to develop an understanding of the weaknesses within the context of your findings without doubting the quality and integrity of your research.

Identify the limitations specific to your study

You don’t have to identify every possible limitation that might have occurred during your research process. Only identify those that may have influenced the quality of your findings and your ability to answer your research question.

Explain study limitations in detail

This explanation should be the most significant portion of your limitation section.

Link each limitation with an interpretation and appraisal of their impact on the study. You’ll have to evaluate and explain whether the error, method, or validity issues influenced the study’s outcome and how.

Propose a direction for future studies and present alternatives

In this section, suggest how researchers can avoid the pitfalls you experienced during your research process.

If an issue with methodology was a limitation, propose alternate methods that may help with a smoother and more conclusive research project. Discuss the pros and cons of your alternate recommendation.

Describe steps taken to minimize each limitation

You probably took steps to try to address or mitigate limitations when you noticed them throughout the course of your research project. Describe these steps in the limitation section.

• Limitation example

“Approaches like stem cell transplantation and vaccination in AD [Alzheimer’s disease] work on a cellular or molecular level in the laboratory. However, translation into clinical settings will remain a challenge for the next decade.”

The authors are saying that even though these methods showed promise in helping people with memory loss when conducted in the lab (in other words, using animal studies), more studies are needed. These may be controlled clinical trials, for example. 

However, the short life span of stem cells outside the lab and the vaccination’s severe inflammatory side effects are limitations. Researchers won’t be able to conduct clinical trials until these issues are overcome.

• How to overcome limitations in research

You’ve already started on the road to overcoming limitations in research by acknowledging that they exist. However, you need to ensure readers don’t mistake weaknesses for errors within your research design.

To do this, you’ll need to justify and explain your rationale for the methods, research design, and analysis tools you chose and how you noticed they may have presented limitations.

Your readers need to know that even when limitations presented themselves, you followed best practices and the ethical standards of your field. You didn’t violate any rules and regulations during your research process.

You’ll also want to reinforce the validity of your conclusions and results with multiple sources, methods, and perspectives. This prevents readers from assuming your findings were derived from a single or biased source.

• Learning and improving starts with limitations in research

Dealing with limitations with transparency and integrity helps identify areas for future improvements and developments. It’s a learning process, providing valuable insights into how you can improve methodologies, expand sample sizes, or explore alternate approaches to further support the validity of your findings.

Editor’s picks

Last updated: 11 January 2024

Last updated: 15 January 2024

Last updated: 25 November 2023

Last updated: 12 May 2023

Last updated: 30 April 2024

Last updated: 18 May 2023

Last updated: 10 April 2023

Latest articles

Related topics, .css-je19u9{-webkit-align-items:flex-end;-webkit-box-align:flex-end;-ms-flex-align:flex-end;align-items:flex-end;display:-webkit-box;display:-webkit-flex;display:-ms-flexbox;display:flex;-webkit-flex-direction:row;-ms-flex-direction:row;flex-direction:row;-webkit-box-flex-wrap:wrap;-webkit-flex-wrap:wrap;-ms-flex-wrap:wrap;flex-wrap:wrap;-webkit-box-pack:center;-ms-flex-pack:center;-webkit-justify-content:center;justify-content:center;row-gap:0;text-align:center;max-width:671px;}@media (max-width: 1079px){.css-je19u9{max-width:400px;}.css-je19u9>span{white-space:pre;}}@media (max-width: 799px){.css-je19u9{max-width:400px;}.css-je19u9>span{white-space:pre;}} decide what to .css-1kiodld{max-height:56px;display:-webkit-box;display:-webkit-flex;display:-ms-flexbox;display:flex;-webkit-align-items:center;-webkit-box-align:center;-ms-flex-align:center;align-items:center;}@media (max-width: 1079px){.css-1kiodld{display:none;}} build next, decide what to build next.

Users report unexpectedly high data usage, especially during streaming sessions.

Users find it hard to navigate from the home page to relevant playlists in the app.

It would be great to have a sleep timer feature, especially for bedtime listening.

I need better filters to find the songs or artists I’m looking for.

Log in or sign up

Get started for free

What are the limitations in research and how to write them?

Learn about the potential limitations in research and how to appropriately address them in order to deliver honest and ethical research.

It is fairly uncommon for researchers to stumble into the term research limitations when working on their research paper. Limitations in research can arise owing to constraints on design, methods, materials, and so on, and these aspects, unfortunately, may have an influence on your subject’s findings.

In this Mind The Graph’s article, we’ll discuss some recommendations for writing limitations in research , provide examples of various common types of limitations, and suggest how to properly present this information.

What are the limitations in research?

The limitations in research are the constraints in design, methods or even researchers’ limitations that affect and influence the interpretation of your research’s ultimate findings. These are limitations on the generalization and usability of findings that emerge from the design of the research and/or the method employed to ensure validity both internally and externally. 

Researchers are usually cautious to acknowledge the limitations of their research in their publications for fear of undermining the research’s scientific validity. No research is faultless or covers every possible angle. As a result, addressing the constraints of your research exhibits honesty and integrity .

Why should include limitations of research in my paper?

Though limitations tackle potential flaws in research, commenting on them at the conclusion of your paper, by demonstrating that you are aware of these limitations and explaining how they impact the conclusions that may be taken from the research, improves your research by disclosing any issues before other researchers or reviewers do . 

Additionally, emphasizing research constraints implies that you have thoroughly investigated the ramifications of research shortcomings and have a thorough understanding of your research problem. 

Limits exist in any research; being honest about them and explaining them would impress researchers and reviewers more than disregarding them. 

Remember that acknowledging a research’s shortcomings offers a chance to provide ideas for future research, but be careful to describe how your study may help to concentrate on these outstanding problems.

Possible limitations examples

Here are some limitations connected to methodology and the research procedure that you may need to explain and discuss in connection to your findings.

Methodological limitations

Sample size.

The number of units of analysis used in your study is determined by the sort of research issue being investigated. It is important to note that if your sample is too small, finding significant connections in the data will be challenging, as statistical tests typically require a larger sample size to ensure a fair representation and this can be limiting. 

Lack of available or reliable data

A lack of data or trustworthy data will almost certainly necessitate limiting the scope of your research or the size of your sample, or it can be a substantial impediment to identifying a pattern and a relevant connection.

Lack of prior research on the subject

Citing previous research papers forms the basis of your literature review and aids in comprehending the research subject you are researching. Yet there may be little if any, past research on your issue.

The measure used to collect data

After finishing your analysis of the findings, you realize that the method you used to collect data limited your capacity to undertake a comprehensive evaluation of the findings. Recognize the flaw by mentioning that future researchers should change the specific approach for data collection.

Issues with research samples and selection

Sampling inaccuracies arise when a probability sampling method is employed to choose a sample, but that sample does not accurately represent the overall population or the relevant group. As a result, your study suffers from “sampling bias” or “selection bias.”

Limitations of the research

When your research requires polling certain persons or a specific group, you may have encountered the issue of limited access to these interviewees. Because of the limited access, you may need to reorganize or rearrange your research. In this scenario, explain why access is restricted and ensure that your findings are still trustworthy and valid despite the constraint.

Time constraints

Practical difficulties may limit the amount of time available to explore a research issue and monitor changes as they occur. If time restrictions have any detrimental influence on your research, recognize this impact by expressing the necessity for a future investigation.

Due to their cultural origins or opinions on observed events, researchers may carry biased opinions, which can influence the credibility of a research. Furthermore, researchers may exhibit biases toward data and conclusions that only support their hypotheses or arguments.

The structure of the limitations section 

The limitations of your research are usually stated at the beginning of the discussion section of your paper so that the reader is aware of and comprehends the limitations prior to actually reading the rest of your findings, or they are stated at the end of the discussion section as an acknowledgment of the need for further research.

The ideal way is to divide your limitations section into three steps: 

1. Identify the research constraints; 

2. Describe in great detail how they affect your research; 

3. Mention the opportunity for future investigations and give possibilities. 

By following this method while addressing the constraints of your research, you will be able to effectively highlight your research’s shortcomings without jeopardizing the quality and integrity of your research.

Present your research or paper in an innovative way

If you want your readers to be engaged and participate in your research, try Mind The Graph tool to add visual assets to your content. Infographics may improve comprehension and are easy to read, just as the Mind The Graph tool is simple to use and offers a variety of templates from which you can select the one that best suits your information.

Subscribe to our newsletter

Exclusive high quality content about effective visual communication in science.

Unlock Your Creativity

Create infographics, presentations and other scientifically-accurate designs without hassle — absolutely free for 7 days!

About Jessica Abbadia

Jessica Abbadia is a lawyer that has been working in Digital Marketing since 2020, improving organic performance for apps and websites in various regions through ASO and SEO. Currently developing scientific and intellectual knowledge for the community's benefit. Jessica is an animal rights activist who enjoys reading and drinking strong coffee.

Content tags

Writing Limitations of Research Study — 4 Reasons Why It Is Important!

It is not unusual for researchers to come across the term limitations of research during their academic paper writing. More often this is interpreted as something terrible. However, when it comes to research study, limitations can help structure the research study better. Therefore, do not underestimate significance of limitations of research study.

Allow us to take you through the context of how to evaluate the limits of your research and conclude an impactful relevance to your results.

Table of Contents

What Are the Limitations of a Research Study?

Every research has its limit and these limitations arise due to restrictions in methodology or research design.  This could impact your entire research or the research paper you wish to publish. Unfortunately, most researchers choose not to discuss their limitations of research fearing it will affect the value of their article in the eyes of readers.

However, it is very important to discuss your study limitations and show it to your target audience (other researchers, journal editors, peer reviewers etc.). It is very important that you provide an explanation of how your research limitations may affect the conclusions and opinions drawn from your research. Moreover, when as an author you state the limitations of research, it shows that you have investigated all the weaknesses of your study and have a deep understanding of the subject. Being honest could impress your readers and mark your study as a sincere effort in research.

Why and Where Should You Include the Research Limitations?

The main goal of your research is to address your research objectives. Conduct experiments, get results and explain those results, and finally justify your research question . It is best to mention the limitations of research in the discussion paragraph of your research article.

At the very beginning of this paragraph, immediately after highlighting the strengths of the research methodology, you should write down your limitations. You can discuss specific points from your research limitations as suggestions for further research in the conclusion of your thesis.

1. Common Limitations of the Researchers

Limitations that are related to the researcher must be mentioned. This will help you gain transparency with your readers. Furthermore, you could provide suggestions on decreasing these limitations in you and your future studies.

2. Limited Access to Information

Your work may involve some institutions and individuals in research, and sometimes you may have problems accessing these institutions. Therefore, you need to redesign and rewrite your work. You must explain your readers the reason for limited access.

3. Limited Time

All researchers are bound by their deadlines when it comes to completing their studies. Sometimes, time constraints can affect your research negatively. However, the best practice is to acknowledge it and mention a requirement for future study to solve the research problem in a better way.

4. Conflict over Biased Views and Personal Issues

Biased views can affect the research. In fact, researchers end up choosing only those results and data that support their main argument, keeping aside the other loose ends of the research.

Types of Limitations of Research

Before beginning your research study, know that there are certain limitations to what you are testing or possible research results. There are different types that researchers may encounter, and they all have unique characteristics, such as:

1. Research Design Limitations

Certain restrictions on your research or available procedures may affect your final results or research outputs. You may have formulated research goals and objectives too broadly. However, this can help you understand how you can narrow down the formulation of research goals and objectives, thereby increasing the focus of your study.

2. Impact Limitations

Even if your research has excellent statistics and a strong design, it can suffer from the influence of the following factors:

• Presence of increasing findings as researched
• Being population specific
• A strong regional focus.

3. Data or statistical limitations

In some cases, it is impossible to collect sufficient data for research or very difficult to get access to the data. This could lead to incomplete conclusion to your study. Moreover, this insufficiency in data could be the outcome of your study design. The unclear, shabby research outline could produce more problems in interpreting your findings.

How to Correctly Structure Your Research Limitations?

There are strict guidelines for narrowing down research questions, wherein you could justify and explain potential weaknesses of your academic paper. You could go through these basic steps to get a well-structured clarity of research limitations:

• Declare that you wish to identify your limitations of research and explain their importance,
• Provide the necessary depth, explain their nature, and justify your study choices.
• Write how you are suggesting that it is possible to overcome them in the future.

In this section, your readers will see that you are aware of the potential weaknesses in your business, understand them and offer effective solutions, and it will positively strengthen your article as you clarify all limitations of research to your target audience.

Know that you cannot be perfect and there is no individual without flaws. You could use the limitations of research as a great opportunity to take on a new challenge and improve the future of research. In a typical academic paper, research limitations may relate to:

1. Formulating your goals and objectives

If you formulate goals and objectives too broadly, your work will have some shortcomings. In this case, specify effective methods or ways to narrow down the formula of goals and aim to increase your level of study focus.

2. Application of your data collection methods in research

If you do not have experience in primary data collection, there is a risk that there will be flaws in the implementation of your methods. It is necessary to accept this, and learn and educate yourself to understand data collection methods.

3. Sample sizes

This depends on the nature of problem you choose. Sample size is of a greater importance in quantitative studies as opposed to qualitative ones. If your sample size is too small, statistical tests cannot identify significant relationships or connections within a given data set.

You could point out that other researchers should base the same study on a larger sample size to get more accurate results.

4. The absence of previous studies in the field you have chosen

Writing a literature review is an important step in any scientific study because it helps researchers determine the scope of current work in the chosen field. It is a major foundation for any researcher who must use them to achieve a set of specific goals or objectives.

However, if you are focused on the most current and evolving research problem or a very narrow research problem, there may be very little prior research on your topic. For example, if you chose to explore the role of Bitcoin as the currency of the future, you may not find tons of scientific papers addressing the research problem as Bitcoins are only a new phenomenon.

It is important that you learn to identify research limitations examples at each step. Whatever field you choose, feel free to add the shortcoming of your work. This is mainly because you do not have many years of experience writing scientific papers or completing complex work. Therefore, the depth and scope of your discussions may be compromised at different levels compared to academics with a lot of expertise. Include specific points from limitations of research. Use them as suggestions for the future.

Have you ever faced a challenge of writing the limitations of research study in your paper? How did you overcome it? What ways did you follow? Were they beneficial? Let us know in the comments below!

Frequently Asked Questions

Setting limitations in our study helps to clarify the outcomes drawn from our research and enhance understanding of the subject. Moreover, it shows that the author has investigated all the weaknesses in the study.

Scope is the range and limitations of a research project which are set to define the boundaries of a project. Limitations are the impacts on the overall study due to the constraints on the research design.

Limitation in research is an impact of a constraint on the research design in the overall study. They are the flaws or weaknesses in the study, which may influence the outcome of the research.

1. Limitations in research can be written as follows: Formulate your goals and objectives 2. Analyze the chosen data collection method and the sample sizes 3. Identify your limitations of research and explain their importance 4. Provide the necessary depth, explain their nature, and justify your study choices 5. Write how you are suggesting that it is possible to overcome them in the future

Excellent article ,,,it has helped me big

This is very helpful information. It has given me an insight on how to go about my study limitations.

Good comments and helpful

Rate this article Cancel Reply

Your email address will not be published.

Enago Academy's Most Popular Articles

• Diversity and Inclusion
• Trending Now

The Silent Struggle: Confronting gender bias in science funding

In the 1990s, Dr. Katalin Kariko’s pioneering mRNA research seemed destined for obscurity, doomed by…

• Promoting Research

Plain Language Summary — Communicating your research to bridge the academic-lay gap

Science can be complex, but does that mean it should not be accessible to the…

Addressing Barriers in Academia: Navigating unconscious biases in the Ph.D. journey

In the journey of academia, a Ph.D. marks a transitional phase, like that of a…

• Manuscripts & Grants
• Reporting Research

Unraveling Research Population and Sample: Understanding their role in statistical inference

Research population and sample serve as the cornerstones of any scientific inquiry. They hold the…

• Manuscript Preparation
• Publishing Research

Research Problem Statement — Find out how to write an impactful one!

What Is a Research Problem Statement? A research problem statement is a clear, concise, and…

How to Develop a Good Research Question? — Types & Examples

5 Effective Ways to Avoid Ghostwriting for Busy Researchers

Top 5 Key Differences Between Methods and Methodology

Sign-up to read more

Subscribe for free to get unrestricted access to all our resources on research writing and academic publishing including:

• 2000+ blog articles
• 50+ Webinars
• 10+ Expert podcasts
• 50+ Infographics
• 10+ Checklists
• Research Guides

We hate spam too. We promise to protect your privacy and never spam you.

I am looking for Editing/ Proofreading services for my manuscript Tentative date of next journal submission:

As a researcher, what do you consider most when choosing an image manipulation detector?

Research Limitations: A Comprehensive Guide

Embarking on a research journey is an exciting endeavor, but every study has its boundaries and constraints. Understanding and transparently acknowledging these limitations is a crucial aspect of scholarly work. In this guide, we'll explore the concept of research limitations, why they matter, and how to effectively address and navigate them in your academic endeavors.

1. Defining Research Limitations:

• Definition: Research limitations are the constraints or shortcomings that affect the scope, applicability, and generalizability of a study.
• Inherent in Research: Every research project, regardless of its scale or significance, possesses limitations.

2. Types of Research Limitations:

• Methodological Limitations: Constraints related to the research design, data collection methods, or analytical techniques.
• Sampling Limitations: Issues associated with the representativeness or size of the study sample.
• Contextual Limitations: Restrictions stemming from the specific time, place, or cultural context of the study.
• Resource Limitations: Constraints related to time, budget, or access to necessary resources.

3. Why Acknowledge Limitations?

• Transparency: Acknowledging limitations demonstrates transparency and honesty in your research.
• Robustness of Findings: Recognizing limitations adds nuance to your findings, making them more robust.
• Future Research Directions: Addressing limitations provides a foundation for future researchers to build upon.

4. Identifying Research Limitations:

• Reflect on Methodology: Consider the strengths and weaknesses of your research design, data collection methods, and analysis.
• Examine Sample Characteristics: Evaluate the representativeness and size of your study sample.
• Consider External Factors: Assess external factors that may impact the generalizability of your findings.

5. How to Address Limitations:

• In the Methodology Section: Clearly articulate limitations in the methodology section of your research paper.
• Offer Solutions: If possible, propose ways to mitigate or address identified limitations.
• Future Research Suggestions: Use limitations as a springboard to suggest areas for future research.

6. Common Phrases to Express Limitations:

• "This study is not without limitations."
• "One limitation of our research is..."
• "It is important to acknowledge the constraints of this study, including..."

7. Examples of Addressing Limitations:

• Example 1 (Methodological): "While our survey provided valuable insights, the reliance on self-reported data introduces the possibility of response bias."
• Example 2 (Sampling): "The small sample size of our study limits the generalizability of our findings to a broader population."
• Example 3 (Resource): "Due to budget constraints, our research was limited to a single geographical location, potentially impacting the external validity."

8. Balancing Strengths and Limitations:

• Emphasize Contributions: Highlight the contributions and strengths of your research alongside the limitations.
• Maintain a Positive Tone: Discuss limitations objectively without undermining the significance of your study.

9. Feedback and Peer Review:

• Seek Feedback: Share your research with peers or mentors to gain valuable insights.
• Peer Review: Embrace the feedback received during the peer-review process to enhance the robustness of your work.

10. Continuous Reflection:

• Throughout the Research Process: Continuously reflect on potential limitations during the entire research process.
• Adjust as Needed: Be willing to adjust your approach as you encounter unforeseen challenges.

Conclusion:

Understanding and effectively addressing research limitations is a hallmark of rigorous and responsible scholarship. By openly acknowledging these constraints, you not only enhance the credibility of your work but also contribute to the broader academic discourse. Embrace the nuances of your research journey, navigate its limitations thoughtfully, and pave the way for future investigations.

Related Guides

• How to Write a Thesis Statement?
• Analyze and Discuss Your Research Findings Like a Pro
• Quantitative Research Methods
• How to Write a Research Question?
• How to Write the Abstract of Your Research Paper?
• How to Write the Body of a Research Paper?

• Link to facebook
• Link to linkedin
• Link to twitter
• Link to youtube
• Writing Tips

Academic Writing Tips: What Are Study Limitations?

4-minute read

• 7th December 2020

An important part of writing up research is to consider whether your study has any limitations. But what are study limitations? And why are they important? In this post, we explain what you need to know.

What Are Study Limitations?

The term “study limitations” refers to anything that may affect the reliability or generalizability of the results in a study or experiment.

This could relate to the design of the research (e.g., your methods or research approach). Or it could be an issue with how the study was carried out (e.g., running out of time and resources before the study is over).

In either case, it’s important to note limitations when writing up your study. Typically, this will be as part of the discussion and analysis . However, different schools may have different guidelines on this, so make sure to check your style guide for advice on where to discuss study limitations.

Why Write About Study Limitations?

It may seem counterintuitive to include limitations when writing up your research, especially if something went wrong. But there are several good reasons to mention study limitations, including:

• It shows you understand that every study will have at least some limitations and that you’re able to critically analyze your own work.
• You can discuss how the limitations affect your analysis, or how you would address the problems you encountered if you did the study again.
• It may offer opportunities for further research .
• It ensures transparency, making your results more useful for others.

In addition, most of the time your professor will spot any problems with your study regardless of whether you mention them. Thus, it’s much better to embrace limitations and make them part of your analysis.

But what exactly counts as a limitation? Typically, they come in two broad types: methodological limitations and researcher limitations.

Find this useful?

Subscribe to our newsletter and get writing tips from our editors straight to your inbox.

Methodological Limitations

Methodological limitations are to do with the way a study was designed and carried out. Some examples include:

• A small or unrepresentative sample may mean one unusual result skews your conclusions. It also limits the degree to which you can generalize your results to a wider or more varied population.
• Flaws in data collection may mean data is incorrect or incomplete. For example, if you rely on self-reporting in a study, you may later find out that one participant was misleading you, making the results unreliable.
• A lack of prior research in the area you are studying, which might make it difficult for you to predict outcomes and draw meaningful conclusions.
• Your chosen research approach may be limited. For instance, if you only work with quantitative data , you may overlook something a qualitative approach would have worked better for.

There are other methodological limitations you may encounter depending on what you’re studying. But, in all cases, it is important to think about your methods and how they may affect your results.

Researcher Limitations

These are factors to do with the attitudes, capabilities, and situation of the researcher. Examples of this type of limitation include:

• Time or budget constraints may limit the extent of the research that can be carried out, or force you to abandon a study before it is complete.
• Limited access to the necessary equipment, documents, or people may mean you had to limit the scope of your study accordingly.
• A lack of linguistic fluency could limit your access to data. For instance, if previous studies in your subject area are mostly in Chinese and you only know English, you may not be able to read key research.
• Cultural and other biases may shape your methodological choices and your interpretation of the data, which may mean you miss other factors .

As above, the key here is thinking about how these limitations may affect your results. If you do this, you can then factor any limitations into your analysis and discussion when writing up your study.

Expert Academic Proofreading

In conclusion, remember that study limitations occur in all research. This isn’t something to worry about or try and hide. However, you should:

• Think about potential limitations when designing your study. This will help you to make informed decisions about your research approach, objectives, and methodology.
• Acknowledge limitations when you write up your research. You can then take them into consideration when you’re analyzing your results.

To ensure your academic writing is clear and consistent, moreover, why not make use of our expert proofreaders ? Sign up for a free trial today.

Share this article:

Post A New Comment

Got content that needs a quick turnaround? Let us polish your work. Explore our editorial business services.

3-minute read

How to Insert a Text Box in a Google Doc

Google Docs is a powerful collaborative tool, and mastering its features can significantly enhance your...

2-minute read

How to Cite the CDC in APA

If you’re writing about health issues, you might need to reference the Centers for Disease...

5-minute read

Six Product Description Generator Tools for Your Product Copy

Introduction If you’re involved with ecommerce, you’re likely familiar with the often painstaking process of...

What Is a Content Editor?

Are you interested in learning more about the role of a content editor and the...

The Benefits of Using an Online Proofreading Service

Proofreading is important to ensure your writing is clear and concise for your readers. Whether...

6 Online AI Presentation Maker Tools

Creating presentations can be time-consuming and frustrating. Trying to construct a visually appealing and informative...

Make sure your writing is the best it can be with our expert English proofreading and editing.

• Affiliate Program

• UNITED STATES
• 台灣 (TAIWAN)
• TÜRKIYE (TURKEY)
• Academic Editing Services
• - Research Paper
• - Journal Manuscript
• - Dissertation
• - College & University Assignments
• Admissions Editing Services
• - Application Essay
• - Personal Statement
• - Recommendation Letter
• - Cover Letter
• - CV/Resume
• Business Editing Services
• - Business Documents
• - Report & Brochure
• - Website & Blog
• Writer Editing Services
• - Script & Screenplay
• Our Editors
• Client Reviews
• Editing & Proofreading Prices
• Wordvice Points
• Partner Discount
• Plagiarism Checker

APA Citation Generator

MLA Citation Generator

Chicago Citation Generator

Vancouver Citation Generator

• - APA Style
• - MLA Style
• - Chicago Style
• - Vancouver Style
• Writing & Editing Guide
• Academic Resources
• Admissions Resources

How to Present the Limitations of the Study Examples

What are the limitations of a study?

The limitations of a study are the elements of methodology or study design that impact the interpretation of your research results. The limitations essentially detail any flaws or shortcomings in your study. Study limitations can exist due to constraints on research design, methodology, materials, etc., and these factors may impact the findings of your study. However, researchers are often reluctant to discuss the limitations of their study in their papers, feeling that bringing up limitations may undermine its research value in the eyes of readers and reviewers.

In spite of the impact it might have (and perhaps because of it) you should clearly acknowledge any limitations in your research paper in order to show readers—whether journal editors, other researchers, or the general public—that you are aware of these limitations and to explain how they affect the conclusions that can be drawn from the research.

In this article, we provide some guidelines for writing about research limitations, show examples of some frequently seen study limitations, and recommend techniques for presenting this information. And after you have finished drafting and have received manuscript editing for your work, you still might want to follow this up with academic editing before submitting your work to your target journal.

Why do I need to include limitations of research in my paper?

Although limitations address the potential weaknesses of a study, writing about them toward the end of your paper actually strengthens your study by identifying any problems before other researchers or reviewers find them.

Furthermore, pointing out study limitations shows that you’ve considered the impact of research weakness thoroughly and have an in-depth understanding of your research topic. Since all studies face limitations, being honest and detailing these limitations will impress researchers and reviewers more than ignoring them.

Where should I put the limitations of the study in my paper?

Some limitations might be evident to researchers before the start of the study, while others might become clear while you are conducting the research. Whether these limitations are anticipated or not, and whether they are due to research design or to methodology, they should be clearly identified and discussed in the discussion section —the final section of your paper. Most journals now require you to include a discussion of potential limitations of your work, and many journals now ask you to place this “limitations section” at the very end of your article. 

Some journals ask you to also discuss the strengths of your work in this section, and some allow you to freely choose where to include that information in your discussion section—make sure to always check the author instructions of your target journal before you finalize a manuscript and submit it for peer review .

Limitations of the Study Examples

There are several reasons why limitations of research might exist. The two main categories of limitations are those that result from the methodology and those that result from issues with the researcher(s).

Common Methodological Limitations of Studies

Limitations of research due to methodological problems can be addressed by clearly and directly identifying the potential problem and suggesting ways in which this could have been addressed—and SHOULD be addressed in future studies. The following are some major potential methodological issues that can impact the conclusions researchers can draw from the research.

Issues with research samples and selection

Sampling errors occur when a probability sampling method is used to select a sample, but that sample does not reflect the general population or appropriate population concerned. This results in limitations of your study known as “sample bias” or “selection bias.”

For example, if you conducted a survey to obtain your research results, your samples (participants) were asked to respond to the survey questions. However, you might have had limited ability to gain access to the appropriate type or geographic scope of participants. In this case, the people who responded to your survey questions may not truly be a random sample.

Insufficient sample size for statistical measurements

When conducting a study, it is important to have a sufficient sample size in order to draw valid conclusions. The larger the sample, the more precise your results will be. If your sample size is too small, it will be difficult to identify significant relationships in the data.

Normally, statistical tests require a larger sample size to ensure that the sample is considered representative of a population and that the statistical result can be generalized to a larger population. It is a good idea to understand how to choose an appropriate sample size before you conduct your research by using scientific calculation tools—in fact, many journals now require such estimation to be included in every manuscript that is sent out for review.

Lack of previous research studies on the topic

Citing and referencing prior research studies constitutes the basis of the literature review for your thesis or study, and these prior studies provide the theoretical foundations for the research question you are investigating. However, depending on the scope of your research topic, prior research studies that are relevant to your thesis might be limited.

When there is very little or no prior research on a specific topic, you may need to develop an entirely new research typology. In this case, discovering a limitation can be considered an important opportunity to identify literature gaps and to present the need for further development in the area of study.

Methods/instruments/techniques used to collect the data

After you complete your analysis of the research findings (in the discussion section), you might realize that the manner in which you have collected the data or the ways in which you have measured variables has limited your ability to conduct a thorough analysis of the results.

For example, you might realize that you should have addressed your survey questions from another viable perspective, or that you were not able to include an important question in the survey. In these cases, you should acknowledge the deficiency or deficiencies by stating a need for future researchers to revise their specific methods for collecting data that includes these missing elements.

Common Limitations of the Researcher(s)

Study limitations that arise from situations relating to the researcher or researchers (whether the direct fault of the individuals or not) should also be addressed and dealt with, and remedies to decrease these limitations—both hypothetically in your study, and practically in future studies—should be proposed.

Limited access to data

If your research involved surveying certain people or organizations, you might have faced the problem of having limited access to these respondents. Due to this limited access, you might need to redesign or restructure your research in a different way. In this case, explain the reasons for limited access and be sure that your finding is still reliable and valid despite this limitation.

Time constraints

Just as students have deadlines to turn in their class papers, academic researchers might also have to meet deadlines for submitting a manuscript to a journal or face other time constraints related to their research (e.g., participants are only available during a certain period; funding runs out; collaborators move to a new institution). The time available to study a research problem and to measure change over time might be constrained by such practical issues. If time constraints negatively impacted your study in any way, acknowledge this impact by mentioning a need for a future study (e.g., a longitudinal study) to answer this research problem.

Conflicts arising from cultural bias and other personal issues

Researchers might hold biased views due to their cultural backgrounds or perspectives of certain phenomena, and this can affect a study’s legitimacy. Also, it is possible that researchers will have biases toward data and results that only support their hypotheses or arguments. In order to avoid these problems, the author(s) of a study should examine whether the way the research problem was stated and the data-gathering process was carried out appropriately.

Steps for Organizing Your Study Limitations Section

When you discuss the limitations of your study, don’t simply list and describe your limitations—explain how these limitations have influenced your research findings. There might be multiple limitations in your study, but you only need to point out and explain those that directly relate to and impact how you address your research questions.

We suggest that you divide your limitations section into three steps: (1) identify the study limitations; (2) explain how they impact your study in detail; and (3) propose a direction for future studies and present alternatives. By following this sequence when discussing your study’s limitations, you will be able to clearly demonstrate your study’s weakness without undermining the quality and integrity of your research.

Step 1. Identify the limitation(s) of the study

• This part should comprise around 10%-20% of your discussion of study limitations.

The first step is to identify the particular limitation(s) that affected your study. There are many possible limitations of research that can affect your study, but you don’t need to write a long review of all possible study limitations. A 200-500 word critique is an appropriate length for a research limitations section. In the beginning of this section, identify what limitations your study has faced and how important these limitations are.

You only need to identify limitations that had the greatest potential impact on: (1) the quality of your findings, and (2) your ability to answer your research question.

Step 2. Explain these study limitations in detail

• This part should comprise around 60-70% of your discussion of limitations.

After identifying your research limitations, it’s time to explain the nature of the limitations and how they potentially impacted your study. For example, when you conduct quantitative research, a lack of probability sampling is an important issue that you should mention. On the other hand, when you conduct qualitative research, the inability to generalize the research findings could be an issue that deserves mention.

Explain the role these limitations played on the results and implications of the research and justify the choice you made in using this “limiting” methodology or other action in your research. Also, make sure that these limitations didn’t undermine the quality of your dissertation .

Step 3. Propose a direction for future studies and present alternatives (optional)

• This part should comprise around 10-20% of your discussion of limitations.

After acknowledging the limitations of the research, you need to discuss some possible ways to overcome these limitations in future studies. One way to do this is to present alternative methodologies and ways to avoid issues with, or “fill in the gaps of” the limitations of this study you have presented.  Discuss both the pros and cons of these alternatives and clearly explain why researchers should choose these approaches.

Make sure you are current on approaches used by prior studies and the impacts they have had on their findings. Cite review articles or scientific bodies that have recommended these approaches and why. This might be evidence in support of the approach you chose, or it might be the reason you consider your choices to be included as limitations. This process can act as a justification for your approach and a defense of your decision to take it while acknowledging the feasibility of other approaches.

P hrases and Tips for Introducing Your Study Limitations in the Discussion Section

The following phrases are frequently used to introduce the limitations of the study:

• “There may be some possible limitations in this study.”
• “The findings of this study have to be seen in light of some limitations.”
•  “The first is the…The second limitation concerns the…”
•  “The empirical results reported herein should be considered in the light of some limitations.”
• “This research, however, is subject to several limitations.”
• “The primary limitation to the generalization of these results is…”
• “Nonetheless, these results must be interpreted with caution and a number of limitations should be borne in mind.”
• “As with the majority of studies, the design of the current study is subject to limitations.”
• “There are two major limitations in this study that could be addressed in future research. First, the study focused on …. Second ….”

For more articles on research writing and the journal submissions and publication process, visit Wordvice’s Academic Resources page.

And be sure to receive professional English editing and proofreading services , including paper editing services , for your journal manuscript before submitting it to journal editors.

Wordvice Resources

Proofreading & Editing Guide

Writing the Results Section for a Research Paper

How to Write a Literature Review

Research Writing Tips: How to Draft a Powerful Discussion Section

How to Captivate Journal Readers with a Strong Introduction

Tips That Will Make Your Abstract a Success!

APA In-Text Citation Guide for Research Writing

Additional Resources

• Diving Deeper into Limitations and Delimitations (PhD student)
• Organizing Your Social Sciences Research Paper: Limitations of the Study (USC Library)
• Research Limitations (Research Methodology)
• How to Present Limitations and Alternatives (UMASS)

Article References

Pearson-Stuttard, J., Kypridemos, C., Collins, B., Mozaffarian, D., Huang, Y., Bandosz, P.,…Micha, R. (2018). Estimating the health and economic effects of the proposed US Food and Drug Administration voluntary sodium reformulation: Microsimulation cost-effectiveness analysis. PLOS. https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1002551

Xu, W.L, Pedersen, N.L., Keller, L., Kalpouzos, G., Wang, H.X., Graff, C,. Fratiglioni, L. (2015). HHEX_23 AA Genotype Exacerbates Effect of Diabetes on Dementia and Alzheimer Disease: A Population-Based Longitudinal Study. PLOS. Retrieved from https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1001853

Organizing Academic Research Papers: Limitations of the Study

• Purpose of Guide
• Design Flaws to Avoid
• Glossary of Research Terms
• Narrowing a Topic Idea
• Broadening a Topic Idea
• Extending the Timeliness of a Topic Idea
• Academic Writing Style
• Choosing a Title
• Making an Outline
• Paragraph Development
• Executive Summary
• Background Information
• The Research Problem/Question
• Theoretical Framework
• Citation Tracking
• Content Alert Services
• Evaluating Sources
• Primary Sources
• Secondary Sources
• Tertiary Sources
• What Is Scholarly vs. Popular?
• Qualitative Methods
• Quantitative Methods
• Using Non-Textual Elements
• Limitations of the Study
• Common Grammar Mistakes
• Avoiding Plagiarism
• Footnotes or Endnotes?
• Further Readings
• Annotated Bibliography
• Dealing with Nervousness
• Using Visual Aids
• Grading Someone Else's Paper
• How to Manage Group Projects
• Multiple Book Review Essay
• Reviewing Collected Essays
• About Informed Consent
• Writing Field Notes
• Writing a Policy Memo
• Writing a Research Proposal
• Acknowledgements

The limitations of the study are those characteristics of design or methodology that impacted or influenced the application or interpretation of the results of your study. They are the constraints on generalizability and utility of findings that are the result of the ways in which you chose to design the study and/or the method used to establish internal and external validity.

Importance of...

Always acknowledge a study's limitations. It is far better for you to identify and acknowledge your study’s limitations than to have them pointed out by your professor and be graded down because you appear to have ignored them.

Keep in mind that acknowledgement of a study's limitations is an opportunity to make suggestions for further research. If you do connect your study's limitations to suggestions for further research, be sure to explain the ways in which these unanswered questions may become more focused because of your study.

Acknowledgement of a study's limitations also provides you with an opportunity to demonstrate to your professor that you have thought critically about the research problem, understood the relevant literature published about it, and correctly assessed the methods chosen for studying the problem. A key objective of the research process is not only discovering new knowledge but also to confront assumptions and explore what we don't know.

Claiming limitiations is a subjective process because you must evaluate the impact of those limitations . Don't just list key weaknesses and the magnitude of a study's limitations. To do so diminishes the validity of your research because it leaves the reader wondering whether, or in what ways, limitation(s) in your study may have impacted the findings and conclusions. Limitations require a critical, overall appraisal and interpretation of their impact. You should answer the question: do these problems with errors, methods, validity, etc. eventually matter and, if so, to what extent?

Structure: How to Structure the Research Limitations Section of Your Dissertation . Dissertations and Theses: An Online Textbook. Laerd.com.

Descriptions of Possible Limitations

All studies have limitations . However, it is important that you restrict your discussion to limitations related to the research problem under investigation. For example, if a meta-analysis of existing literature is not a stated purpose of your research, it should not be discussed as a limitation. Do not apologize for not addressing issues that you did not promise to investigate in your paper.

Here are examples of limitations you may need to describe and to discuss how they possibly impacted your findings. Descriptions of limitations should be stated in the past tense.

Possible Methodological Limitations

• Sample size -- the number of the units of analysis you use in your study is dictated by the type of research problem you are investigating. Note that, if your sample size is too small, it will be difficult to find significant relationships from the data, as statistical tests normally require a larger sample size to ensure a representative distribution of the population and to be considered representative of groups of people to whom results will be generalized or transferred.
• Lack of available and/or reliable data -- a lack of data or of reliable data will likely require you to limit the scope of your analysis, the size of your sample, or it can be a significant obstacle in finding a trend and a meaningful relationship. You need to not only describe these limitations but to offer reasons why you believe data is missing or is unreliable. However, don’t just throw up your hands in frustration; use this as an opportunity to describe the need for future research.
• Lack of prior research studies on the topic -- citing prior research studies forms the basis of your literature review and helps lay a foundation for understanding the research problem you are investigating. Depending on the currency or scope of your research topic, there may be little, if any, prior research on your topic. Before assuming this to be true, consult with a librarian! In cases when a librarian has confirmed that there is a lack of prior research, you may be required to develop an entirely new research typology [for example, using an exploratory rather than an explanatory research design]. Note that this limitation can serve as an important opportunity to describe the need for further research.
• Measure used to collect the data -- sometimes it is the case that, after completing your interpretation of the findings, you discover that the way in which you gathered data inhibited your ability to conduct a thorough analysis of the results. For example, you regret not including a specific question in a survey that, in retrospect, could have helped address a particular issue that emerged later in the study. Acknowledge the deficiency by stating a need in future research to revise the specific method for gathering data.
• Self-reported data -- whether you are relying on pre-existing self-reported data or you are conducting a qualitative research study and gathering the data yourself, self-reported data is limited by the fact that it rarely can be independently verified. In other words, you have to take what people say, whether in interviews, focus groups, or on questionnaires, at face value. However, self-reported data contain several potential sources of bias that should be noted as limitations: (1) selective memory (remembering or not remembering experiences or events that occurred at some point in the past); (2) telescoping [recalling events that occurred at one time as if they occurred at another time]; (3) attribution [the act of attributing positive events and outcomes to one's own agency but attributing negative events and outcomes to external forces]; and, (4) exaggeration [the act of representing outcomes or embellishing events as more significant than is actually suggested from other data].

Possible Limitations of the Researcher

• Access -- if your study depends on having access to people, organizations, or documents and, for whatever reason, access is denied or otherwise limited, the reasons for this need to be described.
• Longitudinal effects -- unlike your professor, who can literally devote years [even a lifetime] to studying a single research problem, the time available to investigate a research problem and to measure change or stability within a sample is constrained by the due date of your assignment. Be sure to choose a topic that does not require an excessive amount of time to complete the literature review, apply the methodology, and gather and interpret the results. If you're unsure, talk to your professor.
• Cultural and other type of bias -- we all have biases, whether we are conscience of them or not. Bias is when a person, place, or thing is viewed or shown in a consistently inaccurate way. It is usually negative, though one can have a positive bias as well. When proof-reading your paper, be especially critical in reviewing how you have stated a problem, selected the data to be studied, what may have been omitted, the manner in which you have ordered events, people, or places and how you have chosen to represent a person, place, or thing, to name a phenomenon, or to use possible words with a positive or negative connotation. Note that if you detect bias in prior research, it must be acknowledged and you should explain what measures were taken to avoid perpetuating bias.
• Fluency in a language -- if your research focuses on measuring the perceived value of after-school tutoring among Mexican-American ESL [English as a Second Language] students, for example, and you are not fluent in Spanish, you are limited in being able to read and interpret Spanish language research studies on the topic. This deficiency should be acknowledged.

Brutus, Stéphane et al. Self-Reported Limitations and Future Directions in Scholarly Reports: Analysis and Recommendations. Journal of Management 39 (January 2013): 48-75; Senunyeme, Emmanuel K. Business Research Methods . Powerpoint Presentation. Regent University of Science and Technology.

Structure and Writing Style

Information about the limitations of your study are generally placed either at the beginning of the discussion section of your paper so the reader knows and understands the limitations before reading the rest of your analysis of the findings, or, the limitations are outlined at the conclusion of the discussion section as an acknowledgement of the need for further study. Statements about a study's limitations should not be buried in the body [middle] of the discussion section unless a limitation is specific to something covered in that part of the paper. If this is the case, though, the limitation should be reiterated at the conclusion of the section.

If you determine that your study is seriously flawed due to important limitations , such as, an inability to acquire critical data, consider reframing it as a pilot study intended to lay the groundwork for a more complete research study in the future. Be sure, though, to specifically explain the ways that these flaws can be successfully overcome in later studies.

But, do not use this as an excuse for not developing a thorough research paper! Review the tab in this guide for developing a research topic . If serious limitations exist, it generally indicates a likelihood that your research problem is too narrowly defined or that the issue or event under study  is too recent and, thus, very little research has been written about it. If serious limitations do emerge, consult with your professor about possible ways to overcome them or how to reframe your study.

When discussing the limitations of your research, be sure to:

• Describe each limitation in detailed but concise terms;
• Explain why each limitation exists;
• Provide the reasons why each limitation could not be overcome using the method(s) chosen to gather the data [cite to other studies that had similar problems when possible];
• Assess the impact of each limitation in relation to  the overall findings and conclusions of your study; and,
• If appropriate, describe how these limitations could point to the need for further research.

Remember that the method you chose may be the source of a significant limitation that has emerged during your interpretation of the results [for example, you didn't ask a particular question in a survey that you later wish you had]. If this is the case, don't panic. Acknowledge it, and explain how applying a different or more robust methodology might address the research problem more effectively in any future study. A underlying goal of scholarly research is not only to prove what works, but to demonstrate what doesn't work or what needs further clarification.

Brutus, Stéphane et al. Self-Reported Limitations and Future Directions in Scholarly Reports: Analysis and Recommendations. Journal of Management 39 (January 2013): 48-75; Ioannidis, John P.A. Limitations are not Properly Acknowledged in the Scientific Literature. Journal of Clinical Epidemiology 60 (2007): 324-329; Pasek, Josh. Writing the Empirical Social Science Research Paper: A Guide for the Perplexed . January 24, 2012. Academia.edu; Structure: How to Structure the Research Limitations Section of Your Dissertation . Dissertations and Theses: An Online Textbook. Laerd.com; What Is an Academic Paper? Institute for Writing Rhetoric. Dartmouth College; Writing the Experimental Report: Methods, Results, and Discussion. The Writing Lab and The OWL. Purdue University.

Writing Tip

Don't Inflate the Importance of Your Findings! After all the hard work and long hours devoted to writing your research paper, it is easy to get carried away with attributing unwarranted importance to what you’ve done. We all want our academic work to be viewed as excellent and worthy of a good grade, but it is important that you understand and openly acknowledge the limitiations of your study. Inflating of the importance of your study's findings in an attempt hide its flaws is a big turn off to your readers. A measure of humility goes a long way!

Another Writing Tip

Negative Results are Not a Limitation!

Negative evidence refers to findings that unexpectedly challenge rather than support your hypothesis. If you didn't get the results you anticipated, it may mean your hypothesis was incorrect and needs to be reformulated, or, perhaps you have stumbled onto something unexpected that warrants further study. Moreover, the absence of an effect may be very telling in many situations, particularly in experimental research designs. In any case, your results may be of importance to others even though they did not support your hypothesis. Do not fall into the trap of thinking that results contrary to what you expected is a limitation to your study. If you carried out the research well, they are simply your results and only require additional interpretation.

Yet Another Writing Tip

A Note about Sample Size Limitations in Qualitative Research

Sample sizes are typically smaller in qualitative research because, as the study goes on, acquiring more data does not necessarily lead to more information. This is because one occurrence of a piece of data, or a code, is all that is necessary to ensure that it becomes part of the analysis framework. However, it remains true that sample sizes that are too small cannot adequately support claims of having achieved valid conclusions and sample sizes that are too large do not permit the deep, naturalistic, and inductive analysis that defines qualitative inquiry. Determining adequate sample size in qualitative research is ultimately a matter of judgment and experience in evaluating the quality of the information collected against the uses to which it will be applied and the particular research method and purposeful sampling strategy employed. If the sample size is found to be a limitation, it may reflect your judgement about the methodological technique chosen [e.g., single life history study versus focus group interviews] rather than the number of respondents used.

Huberman, A. Michael and Matthew B. Miles. Data Management and Analysis Methods. In Handbook of Qualitative Research. Norman K. Denzin and Yvonna S. Lincoln, eds. (Thousand Oaks, CA: Sage, 1994), pp. 428-444.

• << Previous: 8. The Discussion
• Next: 9. The Conclusion >>
• Last Updated: Jul 18, 2023 11:58 AM
• URL: https://library.sacredheart.edu/c.php?g=29803
• QuickSearch
• Library Catalog
• Databases A-Z
• Publication Finder
• Course Reserves
• Citation Linker
• Digital Commons
• Our Website

Research Support

• Ask a Librarian
• Appointments
• Interlibrary Loan (ILL)
• Research Guides
• Databases by Subject
• Citation Help

Using the Library

• Reserve a Group Study Room
• Renew Books
• Honors Study Rooms
• Off-Campus Access
• Library Policies
• Library Technology

User Information

• Grad Students
• Online Students
• COVID-19 Updates
• Staff Directory
• News & Announcements
• Library Newsletter

My Accounts

• Interlibrary Loan
• Staff Site Login

FIND US ON  

21 Research Limitations Examples

Research limitations refer to the potential weaknesses inherent in a study. All studies have limitations of some sort, meaning declaring limitations doesn’t necessarily need to be a bad thing, so long as your declaration of limitations is well thought-out and explained.

Rarely is a study perfect. Researchers have to make trade-offs when developing their studies, which are often based upon practical considerations such as time and monetary constraints, weighing the breadth of participants against the depth of insight, and choosing one methodology or another.

In research, studies can have limitations such as limited scope, researcher subjectivity, and lack of available research tools.

Acknowledging the limitations of your study should be seen as a strength. It demonstrates your willingness for transparency, humility, and submission to the scientific method and can bolster the integrity of the study. It can also inform future research direction.

Typically, scholars will explore the limitations of their study in either their methodology section, their conclusion section, or both.

Research Limitations Examples

Qualitative and quantitative research offer different perspectives and methods in exploring phenomena, each with its own strengths and limitations. So, I’ve split the limitations examples sections into qualitative and quantitative below.

Qualitative Research Limitations

Qualitative research seeks to understand phenomena in-depth and in context. It focuses on the ‘why’ and ‘how’ questions.

It’s often used to explore new or complex issues, and it provides rich, detailed insights into participants’ experiences, behaviors, and attitudes. However, these strengths also create certain limitations, as explained below.

1. Subjectivity

Qualitative research often requires the researcher to interpret subjective data. One researcher may examine a text and identify different themes or concepts as more dominant than others.

Close qualitative readings of texts are necessarily subjective – and while this may be a limitation, qualitative researchers argue this is the best way to deeply understand everything in context.

Suggested Solution and Response: To minimize subjectivity bias, you could consider cross-checking your own readings of themes and data against other scholars’ readings and interpretations. This may involve giving the raw data to a supervisor or colleague and asking them to code the data separately, then coming together to compare and contrast results.

2. Researcher Bias

The concept of researcher bias is related to, but slightly different from, subjectivity.

Researcher bias refers to the perspectives and opinions you bring with you when doing your research.

For example, a researcher who is explicitly of a certain philosophical or political persuasion may bring that persuasion to bear when interpreting data.

In many scholarly traditions, we will attempt to minimize researcher bias through the utilization of clear procedures that are set out in advance or through the use of statistical analysis tools.

However, in other traditions, such as in postmodern feminist research , declaration of bias is expected, and acknowledgment of bias is seen as a positive because, in those traditions, it is believed that bias cannot be eliminated from research, so instead, it is a matter of integrity to present it upfront.

Suggested Solution and Response: Acknowledge the potential for researcher bias and, depending on your theoretical framework , accept this, or identify procedures you have taken to seek a closer approximation to objectivity in your coding and analysis.

3. Generalizability

If you’re struggling to find a limitation to discuss in your own qualitative research study, then this one is for you: all qualitative research, of all persuasions and perspectives, cannot be generalized.

This is a core feature that sets qualitative data and quantitative data apart.

The point of qualitative data is to select case studies and similarly small corpora and dig deep through in-depth analysis and thick description of data.

Often, this will also mean that you have a non-randomized sample size.

While this is a positive – you’re going to get some really deep, contextualized, interesting insights – it also means that the findings may not be generalizable to a larger population that may not be representative of the small group of people in your study.

Suggested Solution and Response: Suggest future studies that take a quantitative approach to the question.

4. The Hawthorne Effect

The Hawthorne effect refers to the phenomenon where research participants change their ‘observed behavior’ when they’re aware that they are being observed.

This effect was first identified by Elton Mayo who conducted studies of the effects of various factors ton workers’ productivity. He noticed that no matter what he did – turning up the lights, turning down the lights, etc. – there was an increase in worker outputs compared to prior to the study taking place.

Mayo realized that the mere act of observing the workers made them work harder – his observation was what was changing behavior.

So, if you’re looking for a potential limitation to name for your observational research study , highlight the possible impact of the Hawthorne effect (and how you could reduce your footprint or visibility in order to decrease its likelihood).

Suggested Solution and Response: Highlight ways you have attempted to reduce your footprint while in the field, and guarantee anonymity to your research participants.

5. Replicability

Quantitative research has a great benefit in that the studies are replicable – a researcher can get a similar sample size, duplicate the variables, and re-test a study. But you can’t do that in qualitative research.

Qualitative research relies heavily on context – a specific case study or specific variables that make a certain instance worthy of analysis. As a result, it’s often difficult to re-enter the same setting with the same variables and repeat the study.

Furthermore, the individual researcher’s interpretation is more influential in qualitative research, meaning even if a new researcher enters an environment and makes observations, their observations may be different because subjectivity comes into play much more. This doesn’t make the research bad necessarily (great insights can be made in qualitative research), but it certainly does demonstrate a weakness of qualitative research.

6. Limited Scope

“Limited scope” is perhaps one of the most common limitations listed by researchers – and while this is often a catch-all way of saying, “well, I’m not studying that in this study”, it’s also a valid point.

No study can explore everything related to a topic. At some point, we have to make decisions about what’s included in the study and what is excluded from the study.

So, you could say that a limitation of your study is that it doesn’t look at an extra variable or concept that’s certainly worthy of study but will have to be explored in your next project because this project has a clearly and narrowly defined goal.

Suggested Solution and Response: Be clear about what’s in and out of the study when writing your research question.

7. Time Constraints

This is also a catch-all claim you can make about your research project: that you would have included more people in the study, looked at more variables, and so on. But you’ve got to submit this thing by the end of next semester! You’ve got time constraints.

And time constraints are a recognized reality in all research.

But this means you’ll need to explain how time has limited your decisions. As with “limited scope”, this may mean that you had to study a smaller group of subjects, limit the amount of time you spent in the field, and so forth.

Suggested Solution and Response: Suggest future studies that will build on your current work, possibly as a PhD project.

8. Resource Intensiveness

Qualitative research can be expensive due to the cost of transcription, the involvement of trained researchers, and potential travel for interviews or observations.

So, resource intensiveness is similar to the time constraints concept. If you don’t have the funds, you have to make decisions about which tools to use, which statistical software to employ, and how many research assistants you can dedicate to the study.

Suggested Solution and Response: Suggest future studies that will gain more funding on the back of this ‘ exploratory study ‘.

9. Coding Difficulties

Data analysis in qualitative research often involves coding, which can be subjective and complex, especially when dealing with ambiguous or contradicting data.

After naming this as a limitation in your research, it’s important to explain how you’ve attempted to address this. Some ways to ‘limit the limitation’ include:

• Triangulation: Have 2 other researchers code the data as well and cross-check your results with theirs to identify outliers that may need to be re-examined, debated with the other researchers, or removed altogether.
• Procedure: Use a clear coding procedure to demonstrate reliability in your coding process. I personally use the thematic network analysis method outlined in this academic article by Attride-Stirling (2001).

Suggested Solution and Response: Triangulate your coding findings with colleagues, and follow a thematic network analysis procedure.

10. Risk of Non-Responsiveness

There is always a risk in research that research participants will be unwilling or uncomfortable sharing their genuine thoughts and feelings in the study.

This is particularly true when you’re conducting research on sensitive topics, politicized topics, or topics where the participant is expressing vulnerability .

This is similar to the Hawthorne effect (aka participant bias), where participants change their behaviors in your presence; but it goes a step further, where participants actively hide their true thoughts and feelings from you.

Suggested Solution and Response: One way to manage this is to try to include a wider group of people with the expectation that there will be non-responsiveness from some participants.

11. Risk of Attrition

Attrition refers to the process of losing research participants throughout the study.

This occurs most commonly in longitudinal studies , where a researcher must return to conduct their analysis over spaced periods of time, often over a period of years.

Things happen to people over time – they move overseas, their life experiences change, they get sick, change their minds, and even die. The more time that passes, the greater the risk of attrition.

Suggested Solution and Response: One way to manage this is to try to include a wider group of people with the expectation that there will be attrition over time.

12. Difficulty in Maintaining Confidentiality and Anonymity

Given the detailed nature of qualitative data , ensuring participant anonymity can be challenging.

If you have a sensitive topic in a specific case study, even anonymizing research participants sometimes isn’t enough. People might be able to induce who you’re talking about.

Sometimes, this will mean you have to exclude some interesting data that you collected from your final report. Confidentiality and anonymity come before your findings in research ethics – and this is a necessary limiting factor.

Suggested Solution and Response: Highlight the efforts you have taken to anonymize data, and accept that confidentiality and accountability place extremely important constraints on academic research.

13. Difficulty in Finding Research Participants

A study that looks at a very specific phenomenon or even a specific set of cases within a phenomenon means that the pool of potential research participants can be very low.

Compile on top of this the fact that many people you approach may choose not to participate, and you could end up with a very small corpus of subjects to explore. This may limit your ability to make complete findings, even in a quantitative sense.

You may need to therefore limit your research question and objectives to something more realistic.

Suggested Solution and Response: Highlight that this is going to limit the study’s generalizability significantly.

14. Ethical Limitations

Ethical limitations refer to the things you cannot do based on ethical concerns identified either by yourself or your institution’s ethics review board.

This might include threats to the physical or psychological well-being of your research subjects, the potential of releasing data that could harm a person’s reputation, and so on.

Furthermore, even if your study follows all expected standards of ethics, you still, as an ethical researcher, need to allow a research participant to pull out at any point in time, after which you cannot use their data, which demonstrates an overlap between ethical constraints and participant attrition.

Suggested Solution and Response: Highlight that these ethical limitations are inevitable but important to sustain the integrity of the research.

For more on Qualitative Research, Explore my Qualitative Research Guide

Quantitative Research Limitations

Quantitative research focuses on quantifiable data and statistical, mathematical, or computational techniques. It’s often used to test hypotheses, assess relationships and causality, and generalize findings across larger populations.

Quantitative research is widely respected for its ability to provide reliable, measurable, and generalizable data (if done well!). Its structured methodology has strengths over qualitative research, such as the fact it allows for replication of the study, which underpins the validity of the research.

However, this approach is not without it limitations, explained below.

1. Over-Simplification

Quantitative research is powerful because it allows you to measure and analyze data in a systematic and standardized way. However, one of its limitations is that it can sometimes simplify complex phenomena or situations.

In other words, it might miss the subtleties or nuances of the research subject.

For example, if you’re studying why people choose a particular diet, a quantitative study might identify factors like age, income, or health status. But it might miss other aspects, such as cultural influences or personal beliefs, that can also significantly impact dietary choices.

When writing about this limitation, you can say that your quantitative approach, while providing precise measurements and comparisons, may not capture the full complexity of your subjects of study.

Suggested Solution and Response: Suggest a follow-up case study using the same research participants in order to gain additional context and depth.

2. Lack of Context

Another potential issue with quantitative research is that it often focuses on numbers and statistics at the expense of context or qualitative information.

Let’s say you’re studying the effect of classroom size on student performance. You might find that students in smaller classes generally perform better. However, this doesn’t take into account other variables, like teaching style , student motivation, or family support.

When describing this limitation, you might say, “Although our research provides important insights into the relationship between class size and student performance, it does not incorporate the impact of other potentially influential variables. Future research could benefit from a mixed-methods approach that combines quantitative analysis with qualitative insights.”

3. Applicability to Real-World Settings

Oftentimes, experimental research takes place in controlled environments to limit the influence of outside factors.

This control is great for isolation and understanding the specific phenomenon but can limit the applicability or “external validity” of the research to real-world settings.

For example, if you conduct a lab experiment to see how sleep deprivation impacts cognitive performance, the sterile, controlled lab environment might not reflect real-world conditions where people are dealing with multiple stressors.

Therefore, when explaining the limitations of your quantitative study in your methodology section, you could state:

“While our findings provide valuable information about [topic], the controlled conditions of the experiment may not accurately represent real-world scenarios where extraneous variables will exist. As such, the direct applicability of our results to broader contexts may be limited.”

Suggested Solution and Response: Suggest future studies that will engage in real-world observational research, such as ethnographic research.

4. Limited Flexibility

Once a quantitative study is underway, it can be challenging to make changes to it. This is because, unlike in grounded research, you’re putting in place your study in advance, and you can’t make changes part-way through.

Your study design, data collection methods, and analysis techniques need to be decided upon before you start collecting data.

For example, if you are conducting a survey on the impact of social media on teenage mental health, and halfway through, you realize that you should have included a question about their screen time, it’s generally too late to add it.

When discussing this limitation, you could write something like, “The structured nature of our quantitative approach allows for consistent data collection and analysis but also limits our flexibility to adapt and modify the research process in response to emerging insights and ideas.”

Suggested Solution and Response: Suggest future studies that will use mixed-methods or qualitative research methods to gain additional depth of insight.

5. Risk of Survey Error

Surveys are a common tool in quantitative research, but they carry risks of error.

There can be measurement errors (if a question is misunderstood), coverage errors (if some groups aren’t adequately represented), non-response errors (if certain people don’t respond), and sampling errors (if your sample isn’t representative of the population).

For instance, if you’re surveying college students about their study habits , but only daytime students respond because you conduct the survey during the day, your results will be skewed.

In discussing this limitation, you might say, “Despite our best efforts to develop a comprehensive survey, there remains a risk of survey error, including measurement, coverage, non-response, and sampling errors. These could potentially impact the reliability and generalizability of our findings.”

Suggested Solution and Response: Suggest future studies that will use other survey tools to compare and contrast results.

6. Limited Ability to Probe Answers

With quantitative research, you typically can’t ask follow-up questions or delve deeper into participants’ responses like you could in a qualitative interview.

For instance, imagine you are surveying 500 students about study habits in a questionnaire. A respondent might indicate that they study for two hours each night. You might want to follow up by asking them to elaborate on what those study sessions involve or how effective they feel their habits are.

However, quantitative research generally disallows this in the way a qualitative semi-structured interview could.

When discussing this limitation, you might write, “Given the structured nature of our survey, our ability to probe deeper into individual responses is limited. This means we may not fully understand the context or reasoning behind the responses, potentially limiting the depth of our findings.”

Suggested Solution and Response: Suggest future studies that engage in mixed-method or qualitative methodologies to address the issue from another angle.

7. Reliance on Instruments for Data Collection

In quantitative research, the collection of data heavily relies on instruments like questionnaires, surveys, or machines.

The limitation here is that the data you get is only as good as the instrument you’re using. If the instrument isn’t designed or calibrated well, your data can be flawed.

For instance, if you’re using a questionnaire to study customer satisfaction and the questions are vague, confusing, or biased, the responses may not accurately reflect the customers’ true feelings.

When discussing this limitation, you could say, “Our study depends on the use of questionnaires for data collection. Although we have put significant effort into designing and testing the instrument, it’s possible that inaccuracies or misunderstandings could potentially affect the validity of the data collected.”

Suggested Solution and Response: Suggest future studies that will use different instruments but examine the same variables to triangulate results.

8. Time and Resource Constraints (Specific to Quantitative Research)

Quantitative research can be time-consuming and resource-intensive, especially when dealing with large samples.

It often involves systematic sampling, rigorous design, and sometimes complex statistical analysis.

If resources and time are limited, it can restrict the scale of your research, the techniques you can employ, or the extent of your data analysis.

For example, you may want to conduct a nationwide survey on public opinion about a certain policy. However, due to limited resources, you might only be able to survey people in one city.

When writing about this limitation, you could say, “Given the scope of our research and the resources available, we are limited to conducting our survey within one city, which may not fully represent the nationwide public opinion. Hence, the generalizability of the results may be limited.”

Suggested Solution and Response: Suggest future studies that will have more funding or longer timeframes.

How to Discuss Your Research Limitations

1. in your research proposal and methodology section.

In the research proposal, which will become the methodology section of your dissertation, I would recommend taking the four following steps, in order:

• Be Explicit about your Scope – If you limit the scope of your study in your research question, aims, and objectives, then you can set yourself up well later in the methodology to say that certain questions are “outside the scope of the study.” For example, you may identify the fact that the study doesn’t address a certain variable, but you can follow up by stating that the research question is specifically focused on the variable that you are examining, so this limitation would need to be looked at in future studies.
• Acknowledge the Limitation – Acknowledging the limitations of your study demonstrates reflexivity and humility and can make your research more reliable and valid. It also pre-empts questions the people grading your paper may have, so instead of them down-grading you for your limitations; they will congratulate you on explaining the limitations and how you have addressed them!
• Explain your Decisions – You may have chosen your approach (despite its limitations) for a very specific reason. This might be because your approach remains, on balance, the best one to answer your research question. Or, it might be because of time and monetary constraints that are outside of your control.
• Highlight the Strengths of your Approach – Conclude your limitations section by strongly demonstrating that, despite limitations, you’ve worked hard to minimize the effects of the limitations and that you have chosen your specific approach and methodology because it’s also got some terrific strengths. Name the strengths.

Overall, you’ll want to acknowledge your own limitations but also explain that the limitations don’t detract from the value of your study as it stands.

2. In the Conclusion Section or Chapter

In the conclusion of your study, it is generally expected that you return to a discussion of the study’s limitations. Here, I recommend the following steps:

• Acknowledge issues faced – After completing your study, you will be increasingly aware of issues you may have faced that, if you re-did the study, you may have addressed earlier in order to avoid those issues. Acknowledge these issues as limitations, and frame them as recommendations for subsequent studies.
• Suggest further research – Scholarly research aims to fill gaps in the current literature and knowledge. Having established your expertise through your study, suggest lines of inquiry for future researchers. You could state that your study had certain limitations, and “future studies” can address those limitations.
• Suggest a mixed methods approach – Qualitative and quantitative research each have pros and cons. So, note those ‘cons’ of your approach, then say the next study should approach the topic using the opposite methodology or could approach it using a mixed-methods approach that could achieve the benefits of quantitative studies with the nuanced insights of associated qualitative insights as part of an in-study case-study.

Overall, be clear about both your limitations and how those limitations can inform future studies.

In sum, each type of research method has its own strengths and limitations. Qualitative research excels in exploring depth, context, and complexity, while quantitative research excels in examining breadth, generalizability, and quantifiable measures. Despite their individual limitations, each method contributes unique and valuable insights, and researchers often use them together to provide a more comprehensive understanding of the phenomenon being studied.

Attride-Stirling, J. (2001). Thematic networks: an analytic tool for qualitative research. Qualitative research , 1 (3), 385-405. ( Source )

Atkinson, P., Delamont, S., Cernat, A., Sakshaug, J., & Williams, R. A. (2021).  SAGE research methods foundations . London: Sage Publications.

Clark, T., Foster, L., Bryman, A., & Sloan, L. (2021).  Bryman’s social research methods . Oxford: Oxford University Press.

Köhler, T., Smith, A., & Bhakoo, V. (2022). Templates in qualitative research methods: Origins, limitations, and new directions.  Organizational Research Methods ,  25 (2), 183-210. ( Source )

Lenger, A. (2019). The rejection of qualitative research methods in economics.  Journal of Economic Issues ,  53 (4), 946-965. ( Source )

Taherdoost, H. (2022). What are different research approaches? Comprehensive review of qualitative, quantitative, and mixed method research, their applications, types, and limitations.  Journal of Management Science & Engineering Research ,  5 (1), 53-63. ( Source )

Walliman, N. (2021).  Research methods: The basics . New York: Routledge.

Chris Drew (PhD)

Dr. Chris Drew is the founder of the Helpful Professor. He holds a PhD in education and has published over 20 articles in scholarly journals. He is the former editor of the Journal of Learning Development in Higher Education. [Image Descriptor: Photo of Chris]

• Chris Drew (PhD) https://helpfulprofessor.com/author/chris-drew-phd/ Social-Emotional Learning (Definition, Examples, Pros & Cons)
• Chris Drew (PhD) https://helpfulprofessor.com/author/chris-drew-phd/ What is Educational Psychology?
• Chris Drew (PhD) https://helpfulprofessor.com/author/chris-drew-phd/ What is IQ? (Intelligence Quotient)
• Chris Drew (PhD) https://helpfulprofessor.com/author/chris-drew-phd/ 5 Top Tips for Succeeding at University

Leave a Comment Cancel Reply

Your email address will not be published. Required fields are marked *

CPS Online Graduate Studies Research Paper (UNH Manchester Library): Limitations of the Study

• Overview of the Research Process for Capstone Projects
• Types of Research Design
• Selecting a Research Problem
• The Title of Your Research Paper
• Before You Begin Writing
• 7 Parts of the Research Paper
• Background Information
• Quanitative and Qualitative Methods
• Qualitative Methods
• Quanitative Methods
• Resources to Help You With the Literature Review
• Non-Textual Elements

Limitations of the Study

• Format of Capstone Research Projects at GSC
• Editing and Proofreading Your Paper
• Acknowledgements
• UNH Scholar's Repository

The limitations of the study are those characteristics of design or methodology that impacted or influenced the interpretation of the findings from your research. They are the constraints on generalizability, applications to practice, and/or utility of findings that are the result of the ways in which you initially chose to design the study and/or the method used to establish internal and external validity.

Price, James H. and Judy Murnan. “Research Limitations and the Necessity of Reporting Them.” American Journal of Health Education 35 (2004): 66-67.

Always acknowledge a study's limitations. It is far better that you identify and acknowledge your study’s limitations than to have them pointed out by your professor and be graded down because you appear to have ignored them.

Keep in mind that acknowledgement of a study's limitations is an opportunity to make suggestions for further research. If you do connect your study's limitations to suggestions for further research, be sure to explain the ways in which these unanswered questions may become more focused because of your study.

Acknowledgement of a study's limitations also provides you with an opportunity to demonstrate that you have thought critically about the research problem, understood the relevant literature published about it, and correctly assessed the methods chosen for studying the problem. A key objective of the research process is not only discovering new knowledge but to also confront assumptions and explore what we don't know.

Claiming limitations is a subjective process because you must evaluate the impact of those limitations . Don't just list key weaknesses and the magnitude of a study's limitations. To do so diminishes the validity of your research because it leaves the reader wondering whether, or in what ways, limitation(s) in your study may have impacted the results and conclusions. Limitations require a critical, overall appraisal and interpretation of their impact. You should answer the question: do these problems with errors, methods, validity, etc. eventually matter and, if so, to what extent?

Price, James H. and Judy Murnan. “Research Limitations and the Necessity of Reporting Them.” American Journal of Health Education 35 (2004): 66-67; Structure: How to Structure the Research Limitations Section of Your Dissertation . Dissertations and Theses: An Online Textbook. Laerd.com.

Descriptions of Possible Limitations

All studies have limitations . However, it is important that you restrict your discussion to limitations related to the research problem under investigation. For example, if a meta-analysis of existing literature is not a stated purpose of your research, it should not be discussed as a limitation. Do not apologize for not addressing issues that you did not promise to investigate in the introduction of your paper.

Here are examples of limitations related to methodology and the research process you may need to describe and to discuss how they possibly impacted your results. Descriptions of limitations should be stated in the past tense because they were discovered after you completed your research.

Possible Methodological Limitations

• Sample size -- the number of the units of analysis you use in your study is dictated by the type of research problem you are investigating. Note that, if your sample size is too small, it will be difficult to find significant relationships from the data, as statistical tests normally require a larger sample size to ensure a representative distribution of the population and to be considered representative of groups of people to whom results will be generalized or transferred. Note that sample size is less relevant in qualitative research.
• Lack of available and/or reliable data -- a lack of data or of reliable data will likely require you to limit the scope of your analysis, the size of your sample, or it can be a significant obstacle in finding a trend and a meaningful relationship. You need to not only describe these limitations but to offer reasons why you believe data is missing or is unreliable. However, don’t just throw up your hands in frustration; use this as an opportunity to describe the need for future research.
• Lack of prior research studies on the topic -- citing prior research studies forms the basis of your literature review and helps lay a foundation for understanding the research problem you are investigating. Depending on the currency or scope of your research topic, there may be little, if any, prior research on your topic. Before assuming this to be true, though, consult with a librarian. In cases when a librarian has confirmed that there is no prior research, you may be required to develop an entirely new research typology [for example, using an exploratory rather than an explanatory research design]. Note again that discovering a limitation can serve as an important opportunity to identify new gaps in the literature and to describe the need for further research.
• Measure used to collect the data -- sometimes it is the case that, after completing your interpretation of the findings, you discover that the way in which you gathered data inhibited your ability to conduct a thorough analysis of the results. For example, you regret not including a specific question in a survey that, in retrospect, could have helped address a particular issue that emerged later in the study. Acknowledge the deficiency by stating a need for future researchers to revise the specific method for gathering data.
• Self-reported data -- whether you are relying on pre-existing data or you are conducting a qualitative research study and gathering the data yourself, self-reported data is limited by the fact that it rarely can be independently verified. In other words, you have to take what people say, whether in interviews, focus groups, or on questionnaires, at face value. However, self-reported data can contain several potential sources of bias that you should be alert to and note as limitations. These biases become apparent if they are incongruent with data from other sources. These are: (1) selective memory [remembering or not remembering experiences or events that occurred at some point in the past]; (2) telescoping [recalling events that occurred at one time as if they occurred at another time]; (3) attribution [the act of attributing positive events and outcomes to one's own agency but attributing negative events and outcomes to external forces]; and, (4) exaggeration [the act of representing outcomes or embellishing events as more significant than is actually suggested from other data].

Possible Limitations of the Researcher

• Access -- if your study depends on having access to people, organizations, or documents and, for whatever reason, access is denied or limited in some way, the reasons for this need to be described.
• Longitudinal effects -- unlike your professor, who can literally devote years [even a lifetime] to studying a single topic, the time available to investigate a research problem and to measure change or stability over time is pretty much constrained by the due date of your assignment. Be sure to choose a research problem that does not require an excessive amount of time to complete the literature review, apply the methodology, and gather and interpret the results. If you're unsure whether you can complete your research within the confines of the assignment's due date, talk to your professor.
• Cultural and other type of bias -- we all have biases, whether we are conscience of them or not. Bias is when a person, place, or thing is viewed or shown in a consistently inaccurate way. Bias is usually negative, though one can have a positive bias as well, especially if that bias reflects your reliance on research that only support for your hypothesis. When proof-reading your paper, be especially critical in reviewing how you have stated a problem, selected the data to be studied, what may have been omitted, the manner in which you have ordered events, people, or places, how you have chosen to represent a person, place, or thing, to name a phenomenon, or to use possible words with a positive or negative connotation.

NOTE:   If you detect bias in prior research, it must be acknowledged and you should explain what measures were taken to avoid perpetuating that bias.

• Fluency in a language -- if your research focuses on measuring the perceived value of after-school tutoring among Mexican-American ESL [English as a Second Language] students, for example, and you are not fluent in Spanish, you are limited in being able to read and interpret Spanish language research studies on the topic. This deficiency should be acknowledged.

Aguinis, Hermam and Jeffrey R. Edwards. “Methodological Wishes for the Next Decade and How to Make Wishes Come True.” Journal of Management Studies 51 (January 2014): 143-174; Brutus, Stéphane et al. "Self-Reported Limitations and Future Directions in Scholarly Reports: Analysis and Recommendations." Journal of Management 39 (January 2013): 48-75; Senunyeme, Emmanuel K. Business Research Methods . Powerpoint Presentation. Regent University of Science and Technology; ter Riet, Gerben et al. “All That Glitters Isn't Gold: A Survey on Acknowledgment of Limitations in Biomedical Studies.” PLOS One 8 (November 2013): 1-6.

Structure and Writing Style

Information about the limitations of your study are generally placed either at the beginning of the discussion section of your paper so the reader knows and understands the limitations before reading the rest of your analysis of the findings, or, the limitations are outlined at the conclusion of the discussion section as an acknowledgement of the need for further study. Statements about a study's limitations should not be buried in the body [middle] of the discussion section unless a limitation is specific to something covered in that part of the paper. If this is the case, though, the limitation should be reiterated at the conclusion of the section. If you determine that your study is seriously flawed due to important limitations, such as, an inability to acquire critical data, consider reframing it as an exploratory study intended to lay the groundwork for a more complete research study in the future. Be sure, though, to specifically explain the ways that these flaws can be successfully overcome in a new study. But, do not use this as an excuse for not developing a thorough research paper! Review the tab in this guide for developing a research topic. If serious limitations exist, it generally indicates a likelihood that your research problem is too narrowly defined or that the issue or event under study is too recent and, thus, very little research has been written about it. If serious limitations do emerge, consult with your professor about possible ways to overcome them or how to revise your study. When discussing the limitations of your research, be sure to: Describe each limitation in detailed but concise terms; Explain why each limitation exists; Provide the reasons why each limitation could not be overcome using the method(s) chosen to acquire or gather the data [cite to other studies that had similar problems when possible]; Assess the impact of each limitation in relation to the overall findings and conclusions of your study; and, If appropriate, describe how these limitations could point to the need for further research. Remember that the method you chose may be the source of a significant limitation that has emerged during your interpretation of the results [for example, you didn't interview a group of people that you later wish you had]. If this is the case, don't panic. Acknowledge it, and explain how applying a different or more robust methodology might address the research problem more effectively in a future study. A underlying goal of scholarly research is not only to show what works, but to demonstrate what doesn't work or what needs further clarification. Aguinis, Hermam and Jeffrey R. Edwards. “Methodological Wishes for the Next Decade and How to Make Wishes Come True.” Journal of Management Studies 51 (January 2014): 143-174; Brutus, Stéphane et al. "Self-Reported Limitations and Future Directions in Scholarly Reports: Analysis and Recommendations." Journal of Management 39 (January 2013): 48-75; Ioannidis, John P.A. "Limitations are not Properly Acknowledged in the Scientific Literature." Journal of Clinical Epidemiology 60 (2007): 324-329; Pasek, Josh. Writing the Empirical Social Science Research Paper: A Guide for the Perplexed. January 24, 2012. Academia.edu; Structure: How to Structure the Research Limitations Section of Your Dissertation. Dissertations and Theses: An Online Textbook. Laerd.com; What Is an Academic Paper? Institute for Writing Rhetoric. Dartmouth College; Writing the Experimental Report: Methods, Results, and Discussion. The Writing Lab and The OWL. Purdue University.

Information about the limitations of your study are generally placed either at the beginning of the discussion section of your paper so the reader knows and understands the limitations before reading the rest of your analysis of the findings, or, the limitations are outlined at the conclusion of the discussion section as an acknowledgement of the need for further study. Statements about a study's limitations should not be buried in the body [middle] of the discussion section unless a limitation is specific to something covered in that part of the paper. If this is the case, though, the limitation should be reiterated at the conclusion of the section.

If you determine that your study is seriously flawed due to important limitations , such as, an inability to acquire critical data, consider reframing it as an exploratory study intended to lay the groundwork for a more complete research study in the future. Be sure, though, to specifically explain the ways that these flaws can be successfully overcome in a new study.

But, do not use this as an excuse for not developing a thorough research paper! Review the tab in this guide for developing a research topic . If serious limitations exist, it generally indicates a likelihood that your research problem is too narrowly defined or that the issue or event under study is too recent and, thus, very little research has been written about it. If serious limitations do emerge, consult with your professor about possible ways to overcome them or how to revise your study.

When discussing the limitations of your research, be sure to:

• Describe each limitation in detailed but concise terms;
• Explain why each limitation exists;
• Provide the reasons why each limitation could not be overcome using the method(s) chosen to acquire or gather the data [cite to other studies that had similar problems when possible];
• Assess the impact of each limitation in relation to the overall findings and conclusions of your study; and,
• If appropriate, describe how these limitations could point to the need for further research.

Remember that the method you chose may be the source of a significant limitation that has emerged during your interpretation of the results [for example, you didn't interview a group of people that you later wish you had]. If this is the case, don't panic. Acknowledge it, and explain how applying a different or more robust methodology might address the research problem more effectively in a future study. A underlying goal of scholarly research is not only to show what works, but to demonstrate what doesn't work or what needs further clarification.

Aguinis, Hermam and Jeffrey R. Edwards. “Methodological Wishes for the Next Decade and How to Make Wishes Come True.” Journal of Management Studies 51 (January 2014): 143-174; Brutus, Stéphane et al. "Self-Reported Limitations and Future Directions in Scholarly Reports: Analysis and Recommendations." Journal of Management 39 (January 2013): 48-75; Ioannidis, John P.A. "Limitations are not Properly Acknowledged in the Scientific Literature." Journal of Clinical Epidemiology 60 (2007): 324-329; Pasek, Josh. Writing the Empirical Social Science Research Paper: A Guide for the Perplexed . January 24, 2012. Academia.edu; Structure: How to Structure the Research Limitations Section of Your Dissertation . Dissertations and Theses: An Online Textbook. Laerd.com; What Is an Academic Paper? Institute for Writing Rhetoric. Dartmouth College; Writing the Experimental Report: Methods, Results, and Discussion . The Writing Lab and The OWL. Purdue University.

• << Previous: The Discussion
• Next: Conclusion >>
• Last Updated: Nov 6, 2023 1:43 PM
• URL: https://libraryguides.unh.edu/cpsonlinegradpaper

Research Limitations & Delimitations

What they are and how they’re different (with examples)

By: Derek Jansen (MBA) | Expert Reviewed By: David Phair (PhD) | September 2022

If you’re new to the world of research, you’ve probably heard the terms “ research limitations ” and “ research delimitations ” being thrown around, often quite loosely. In this post, we’ll unpack what both of these mean, how they’re similar and how they’re different – so that you can write up these sections the right way.

Overview: Limitations vs Delimitations

• Are they the same?
• What are research limitations
• What are research delimitations
• Limitations vs delimitations

First things first…

Let’s start with the most important takeaway point of this post – research limitations and research delimitations are not the same – but they are related to each other (we’ll unpack that a little later). So, if you hear someone using these two words interchangeably, be sure to share this post with them!

Research Limitations

Research limitations are, at the simplest level, the weaknesses of the study , based on factors that are often outside of your control as the researcher. These factors could include things like time , access to funding, equipment , data or participants . For example, if you weren’t able to access a random sample of participants for your study and had to adopt a convenience sampling strategy instead, that would impact the generalizability of your findings and therefore reflect a limitation of your study.

Research limitations can also emerge from the research design itself . For example, if you were undertaking a correlational study, you wouldn’t be able to infer causality (since correlation doesn’t mean certain causation). Similarly, if you utilised online surveys to collect data from your participants, you naturally wouldn’t be able to get the same degree of rich data that you would from in-person interviews .

Simply put, research limitations reflect the shortcomings of a study , based on practical (or theoretical) constraints that the researcher faced. These shortcomings limit what you can conclude from a study, but at the same time, present a foundation for future research . Importantly, all research has limitations , so there’s no need to hide anything here – as long as you discuss how the limitations might affect your findings, it’s all good.

Research Delimitations

Alright, now that we’ve unpacked the limitations, let’s move on to the delimitations .

Research delimitations are similar to limitations in that they also “ limit ” the study, but their focus is entirely different. Specifically, the delimitations of a study refer to the scope of the research aims and research questions . In other words, delimitations reflect the choices you, as the researcher, intentionally make in terms of what you will and won’t try to achieve with your study. In other words, what your research aims and research questions will and won’t include.

As we’ve spoken about many times before, it’s important to have a tight, narrow focus for your research, so that you can dive deeply into your topic, apply your energy to one specific area and develop meaningful insights. If you have an overly broad scope or unfocused topic, your research will often pull in multiple, even opposing directions, and you’ll just land up with a muddy mess of findings .

So, the delimitations section is where you’ll clearly state what your research aims and research questions will focus on – and just as importantly, what they will exclude . For example, you might investigate a widespread phenomenon, but choose to focus your study on a specific age group, ethnicity or gender. Similarly, your study may focus exclusively on one country, city or even organization. As long as the scope is well justified (in other words, it represents a novel, valuable research topic), this is perfectly acceptable – in fact, it’s essential. Remember, focus is your friend.

Need a helping hand?

Conclusion: Limitations vs Delimitations

Ok, so let’s recap.

Research limitations and research delimitations are related in that they both refer to “limits” within a study. But, they are distinctly different. Limitations reflect the shortcomings of your study, based on practical or theoretical constraints that you faced.

Contrasted to that, delimitations reflect the choices that you made in terms of the focus and scope of your research aims and research questions. If you want to learn more about research aims and questions, you can check out this video post , where we unpack those concepts in detail.

Psst... there’s more!

This post was based on one of our popular Research Bootcamps . If you're working on a research project, you'll definitely want to check this out ...

You Might Also Like:

18 Comments

Good clarification of ideas on how a researcher ought to do during Process of choice

Thank you so much for this very simple but explicit explanation on limitation and delimitation. It has so helped me to develop my masters proposal. hope to recieve more from your site as time progresses

Thank you for this explanation – very clear.

Thanks for the explanation, really got it well.

This website is really helpful for my masters proposal

Thank you very much for helping to explain these two terms

I spent almost the whole day trying to figure out the differences

when I came across your notes everything became very clear

thanks for the clearly outlined explanation on the two terms, limitation and delimitation.

Very helpful Many thanks 🙏

Excellent it resolved my conflict .

I would like you to assist me please. If in my Research, I interviewed some participants and I submitted Questionnaires to other participants to answered to the questions, in the same organization, Is this a Qualitative methodology , a Quantitative Methodology or is it a Mixture Methodology I have used in my research? Please help me

How do I cite this article in APA format

Really so great ,finally have understood it’s difference now

Getting more clear regarding Limitations and Delimitation and concepts

I really appreciate your apt and precise explanation of the two concepts namely ; Limitations and Delimitations.

This is a good sources of research information for learners.

thank you for this, very helpful to researchers

Very good explained

Great and clear explanation, after a long confusion period on the two words, i can now explain to someone with ease.

Submit a Comment Cancel reply

Your email address will not be published. Required fields are marked *

Save my name, email, and website in this browser for the next time I comment.

• Print Friendly

Submit Manuscript

Easy Online Form

Get Newsletter

Sign Up Today

How to Write About the Limitations of a Scientific Study

Home » Writing the Manuscript » How to Write About the Limitations of a Scientific Study

You’ve analyzed your results and reached some conclusions. Now, you’re ready to tell the world about what you’ve found and convince editors, peer reviewers, and readers that it’s important. So how do you tackle the task of also telling them about the limitations of your work?

How to write about the limitations of a study

No study is perfect, no matter how elegant its design may be, and many journals require authors to write a section at the end of the discussion about the limitations of their study. For some studies, these limitations will be obvious: small sample size, multiple comparisons without corrections, observational design and risk for confounding. For other designs, the limitations may be less obvious, but you’ll still need to list them.

Six tips for writing your limitations section

• Focus on weaknesses in your design and analyses, rather than results.
• Start with a bold statement: “This study has some limitations.” Don’t try to soften it with less obvious language.
• Enumerate the limitations, if you can. If you have three limitations to discuss, say so: “This study has three main limitations.”
• Be direct about what they are. “The first limitation is the small number of participants.”
• Explain if needed, but without being defensive. “Because this condition is so rare, we anticipated that recruitment might not meet targets. However, also because the condition is rare, the findings of this study offer new, potentially useful information for this patient population.”
• Signal that you are wrapping up your limitations: “Finally, we could not control for every possible lifestyle factor, and the observational nature of this design leaves the possibility of residual confounding.”

What not to include in the limitations section

You do not need to include every single thing that you personally view as a limitation of the work. For example, if you were late in making a measurement one day, but that timing did not affect outcomes, you probably don’t need to mention it.

Do not be extremely defensive. Don’t expend a lot of language explaining why your work had the limitation. See above for an example of how to explain a limitation while still emphasizing the importance of your work.

Usually, avoid pointing fingers in an accusatory way at other studies. If your work has a specific limitation because of real-world considerations, you can point that out, rather than saying as justification that some other author group or groups did the same thing.

In a similar vein, the limitations section is not usually the place to compare a limitation of your study favorably to the limitations of other studies. For example, you should not say, “We had only 25 participants, but Smith et al. had only 12 and they still published their results.” That comes across as defensive and uncollegial.

Where do you comment on the strengths?

The usual practice is to place the strengths of a study ahead of the limitations. Most authors will list the strengths, beginning with a phrase such as, “Our study had several strengths,” and then briefly describing what those are. As with limitations, these strengths usually will relate to design: large population, excellent controls, multiple adjustments, or double-blind design. If your design is considered more stringent than what others have used before (e.g., a randomized trial as opposed to an observational study), that’s a particular strength. When you’ve listed your strengths, then you move to your limitations, using phrasing such as, “Our study also had some limitations.”

Acknowledging a study’s limitations is an important part of the process of science and of communicating your results. It shows that you are willing to mention and discuss the weaknesses as well as the strengths of your work and suggests an intellectually honest presentation of your findings.

San Francisco Edit specializes in scientific editing in the United States and we work with scientists from all over the world.

Sign up for our newsletter, latest from the blog.

Scientific Editing for Non-Native English Speakers: Enhance Your Research Publication Chances

Writing a Research Methodology Section: Best Practices for Clarity and Precision

Writing an Introduction for a Scientific Paper: Aligning with Journal Requirements

How to Write Academic Abstracts: From Draft to Polish

• Knowledge Center
• English Grammar
• Getting Published
• Journal Submission
• Marketing Your Paper and Yourself
• Peer Reviewing a Scientific Paper
• Presenting Your Research
• Thesis vs Dissertation
• What is Scientific Editing
• Why Edit and Types of Editing
• Writing the Manuscript
• Scientific Editing
• Business Editing
• Language Editing
• Newsletters
• Testimonials
• Areas of Expertise

San Francisco Edit 1755 Jackson Street Suite 610 San Francisco, CA 94109 Email: [email protected]

Copyright © 2003-2022 San Francisco Edit. All Rights Reserved.

Join 90,000+ Scientist Who Get Useful Tips For Writing Better Manuscripts

Don't miss out on future newsletters. sign up now..

Research Limitations

It is for sure that your research will have some limitations and it is normal. However, it is critically important for you to be striving to minimize the range of scope of limitations throughout the research process.  Also, you need to provide the acknowledgement of your research limitations in conclusions chapter honestly.

It is always better to identify and acknowledge shortcomings of your work, rather than to leave them pointed out to your by your dissertation assessor. While discussing your research limitations, don’t just provide the list and description of shortcomings of your work. It is also important for you to explain how these limitations have impacted your research findings.

Your research may have multiple limitations, but you need to discuss only those limitations that directly relate to your research problems. For example, if conducting a meta-analysis of the secondary data has not been stated as your research objective, no need to mention it as your research limitation.

Research limitations in a typical dissertation may relate to the following points:

1. Formulation of research aims and objectives . You might have formulated research aims and objectives too broadly. You can specify in which ways the formulation of research aims and objectives could be narrowed so that the level of focus of the study could be increased.

2. Implementation of data collection method . Because you do not have an extensive experience in primary data collection (otherwise you would not be reading this book), there is a great chance that the nature of implementation of data collection method is flawed.

3. Sample size. Sample size depends on the nature of the research problem. If sample size is too small, statistical tests would not be able to identify significant relationships within data set. You can state that basing your study in larger sample size could have generated more accurate results. The importance of sample size is greater in quantitative studies compared to qualitative studies.

4. Lack of previous studies in the research area . Literature review is an important part of any research, because it helps to identify the scope of works that have been done so far in research area. Literature review findings are used as the foundation for the researcher to be built upon to achieve her research objectives.

However, there may be little, if any, prior research on your topic if you have focused on the most contemporary and evolving research problem or too narrow research problem. For example, if you have chosen to explore the role of Bitcoins as the future currency, you may not be able to find tons of scholarly paper addressing the research problem, because Bitcoins are only a recent phenomenon.

5. Scope of discussions . You can include this point as a limitation of your research regardless of the choice of the research area. Because (most likely) you don’t have many years of experience of conducing researches and producing academic papers of such a large size individually, the scope and depth of discussions in your paper is compromised in many levels compared to the works of experienced scholars.

You can discuss certain points from your research limitations as the suggestion for further research at conclusions chapter of your dissertation.

My e-book,  The Ultimate Guide to Writing a Dissertation in Business Studies: a step by step assistance  offers practical assistance to complete a dissertation with minimum or no stress. The e-book covers all stages of writing a dissertation starting from the selection to the research area to submitting the completed version of the work within the deadline. John Dudovskiy

• Privacy Policy

Home » Scope of the Research – Writing Guide and Examples

Scope of the Research – Writing Guide and Examples

Table of Contents

Scope of the Research

Scope of research refers to the range of topics, areas, and subjects that a research project intends to cover. It is the extent and limitations of the study, defining what is included and excluded in the research.

The scope of a research project depends on various factors, such as the research questions , objectives , methodology, and available resources. It is essential to define the scope of the research project clearly to avoid confusion and ensure that the study addresses the intended research questions.

How to Write Scope of the Research

Writing the scope of the research involves identifying the specific boundaries and limitations of the study. Here are some steps you can follow to write a clear and concise scope of the research:

• Identify the research question: Start by identifying the specific question that you want to answer through your research . This will help you focus your research and define the scope more clearly.
• Define the objectives: Once you have identified the research question, define the objectives of your study. What specific goals do you want to achieve through your research?
• Determine the population and sample: Identify the population or group of people that you will be studying, as well as the sample size and selection criteria. This will help you narrow down the scope of your research and ensure that your findings are applicable to the intended audience.
• Identify the variables: Determine the variables that will be measured or analyzed in your research. This could include demographic variables, independent variables , dependent variables , or any other relevant factors.
• Define the timeframe: Determine the timeframe for your study, including the start and end date, as well as any specific time intervals that will be measured.
• Determine the geographical scope: If your research is location-specific, define the geographical scope of your study. This could include specific regions, cities, or neighborhoods that you will be focusing on.
• Outline the limitations: Finally, outline any limitations or constraints of your research, such as time, resources, or access to data. This will help readers understand the scope and applicability of your research findings.

Examples of the Scope of the Research

Some Examples of the Scope of the Research are as follows:

Title : “Investigating the impact of artificial intelligence on job automation in the IT industry”

Scope of Research:

This study aims to explore the impact of artificial intelligence on job automation in the IT industry. The research will involve a qualitative analysis of job postings, identifying tasks that can be automated using AI. The study will also assess the potential implications of job automation on the workforce, including job displacement, job creation, and changes in job requirements.

Title : “Developing a machine learning model for predicting cyberattacks on corporate networks”

This study will develop a machine learning model for predicting cyberattacks on corporate networks. The research will involve collecting and analyzing network traffic data, identifying patterns and trends that are indicative of cyberattacks. The study aims to build an accurate and reliable predictive model that can help organizations identify and prevent cyberattacks before they occur.

Title: “Assessing the usability of a mobile app for managing personal finances”

This study will assess the usability of a mobile app for managing personal finances. The research will involve conducting a usability test with a group of participants, evaluating the app’s ease of use, efficiency, and user satisfaction. The study aims to identify areas of the app that need improvement, and to provide recommendations for enhancing its usability and user experience.

Title : “Exploring the effects of mindfulness meditation on stress reduction among college students”

This study aims to investigate the impact of mindfulness meditation on reducing stress levels among college students. The research will involve a randomized controlled trial with two groups: a treatment group that receives mindfulness meditation training and a control group that receives no intervention. The study will examine changes in stress levels, as measured by self-report questionnaires, before and after the intervention.

Title: “Investigating the impact of social media on body image dissatisfaction among young adults”

This study will explore the relationship between social media use and body image dissatisfaction among young adults. The research will involve a cross-sectional survey of participants aged 18-25, assessing their social media use, body image perceptions, and self-esteem. The study aims to identify any correlations between social media use and body image dissatisfaction, and to determine if certain social media platforms or types of content are particularly harmful.

When to Write Scope of the Research

Here is a guide on When to Write the Scope of the Research:

• Before starting your research project, it’s important to clearly define the scope of your study. This will help you stay focused on your research question and avoid getting sidetracked by irrelevant information.
• The scope of the research should be determined by the research question or problem statement. It should outline what you intend to investigate and what you will not be investigating.
• The scope should also take into consideration any limitations of the study, such as time, resources, or access to data. This will help you realistically plan and execute your research.
• Writing the scope of the research early in the research process can also help you refine your research question and identify any gaps in the existing literature that your study can address.
• It’s important to revisit the scope of the research throughout the research process to ensure that you stay on track and make any necessary adjustments.
• The scope of the research should be clearly communicated in the research proposal or study protocol to ensure that all stakeholders are aware of the research objectives and limitations.
• The scope of the research should also be reflected in the research design, methods, and analysis plan. This will ensure that the research is conducted in a systematic and rigorous manner that is aligned with the research objectives.
• The scope of the research should be written in a clear and concise manner, using language that is accessible to all stakeholders, including those who may not be familiar with the research topic or methodology.
• When writing the scope of the research, it’s important to be transparent about any assumptions or biases that may influence the research findings. This will help ensure that the research is conducted in an ethical and responsible manner.
• The scope of the research should be reviewed and approved by the research supervisor, committee members, or other relevant stakeholders. This will ensure that the research is feasible, relevant, and contributes to the field of study.
• Finally, the scope of the research should be clearly stated in the research report or dissertation to provide context for the research findings and conclusions. This will help readers understand the significance of the research and its contribution to the field of study.

Purpose of Scope of the Research

Purposes of Scope of the Research are as follows:

• Defines the boundaries and extent of the study.
• Determines the specific objectives and research questions to be addressed.
• Provides direction and focus for the research.
• Helps to identify the relevant theories, concepts, and variables to be studied.
• Enables the researcher to select the appropriate research methodology and techniques.
• Allows for the allocation of resources (time, money, personnel) to the research.
• Establishes the criteria for the selection of the sample and data collection methods.
• Facilitates the interpretation and generalization of the results.
• Ensures the ethical considerations and constraints are addressed.
• Provides a framework for the presentation and dissemination of the research findings.

Advantages of Scope of the Research

Here are some advantages of having a well-defined scope of research:

• Provides clarity and focus: Defining the scope of research helps to provide clarity and focus to the study. This ensures that the research stays on track and does not deviate from its intended purpose.
• Helps to manage resources: Knowing the scope of research allows researchers to allocate resources effectively. This includes managing time, budget, and personnel required to conduct the study.
• Improves the quality of research: A well-defined scope of research helps to ensure that the study is designed to achieve specific objectives. This helps to improve the quality of the research by reducing the likelihood of errors or bias.
• Facilitates communication: A clear scope of research enables researchers to communicate the goals and objectives of the study to stakeholders, such as funding agencies or participants. This facilitates understanding and enhances cooperation.
• Enables replication : A well-defined scope of research makes it easier to replicate the study in the future. This allows other researchers to validate the findings and build upon them, leading to the advancement of knowledge in the field.
• Increases the relevance of research: Defining the scope of research helps to ensure that the study is relevant to the problem or issue being investigated. This increases the likelihood that the findings will be useful and applicable to real-world situations.
• Reduces the risk of scope creep : Scope creep occurs when the research expands beyond the original scope, leading to an increase in the time, cost, and resources required to complete the study. A clear definition of the scope of research helps to reduce the risk of scope creep by establishing boundaries and limitations.
• Enhances the credibility of research: A well-defined scope of research helps to enhance the credibility of the study by ensuring that it is designed to achieve specific objectives and answer specific research questions. This makes it easier for others to assess the validity and reliability of the study.
• Provides a framework for decision-making : A clear scope of research provides a framework for decision-making throughout the research process. This includes decisions related to data collection, analysis, and interpretation.

Scope of the Research Vs Scope of the Project

About the author.

Muhammad Hassan

Researcher, Academic Writer, Web developer

You may also like

How to Cite Research Paper – All Formats and...

Data Collection – Methods Types and Examples

Delimitations in Research – Types, Examples and...

Research Paper Format – Types, Examples and...

Research Process – Steps, Examples and Tips

Research Design – Types, Methods and Examples

• Career Resources
• Addressing Trauma in Students
• BSW Holders: Advanced Standing
• Academics FAQs
• CASAC Credentialing
• Gerontology and Palliative Care Certificate
• Application and Admissions Requirements
• Tuition and Financial Aid
• Admissions FAQs
• A Letter from the Dean
• Our Faculty
• Student Resources
• Student Support
• The Heights: Virtual Learning
• Licensing and CE
• Alumni Network

Social Work Research and Evaluation Foundations

Studying social work and its effect on societies is essential to understanding and enhancing human and community well-being. By effectively measuring and evaluating social work outcomes, practitioners can employ evidence-based social work practices and evidence-based treatments (EBTs) to provide structured approaches to addressing client needs. For example, in the case of a client with an anxiety disorder, cognitive behavioral therapy (CBT) and behavioral science can be applied as efficient and ethical frameworks to address communication and collaboration problems. 1

Read on to learn more about the essential role of social work research and evaluation.

The Importance of Research and Evaluation in Social Work Practice

By rigorously assessing and evaluating social work studies, researchers can better identify the most effective strategies to achieve their client’s objectives. 2 Instead of trial and error, a data-driven approach ensures researchers make better use of the resources available to them.

Evidence-based interventions result from analyzing past research findings. After choosing a solution, researchers test it to verify replicability in multiple real-world scenarios before it’s deemed successful. 3 New intervention methods are constantly being standardized across the social work field of study, letting practitioners choose from a wider range of tools and techniques suitable for their study. These are usually taught in more advanced research courses in graduate or master's programs.

For example, at Wurzweiler School of Social Work, students participate in individual research projects and learn the basics of conducting social work research . This includes learning how to use measurement instruments; logic of research design, including sampling and design selection; ethical and legal issues; quantitative and qualitative modes of observation; analysis of data; use of computers and computer programs; and research report writing.

Methodologies and Approaches for Conducting Social Work Research

Conducting social work research requires access to large amounts of data supplied by study participants, which can be historical data or up-to-date surveys. 4 Due to social work’s multifaceted nature, researchers must then use their understanding of how psychosocial factors intersect. They need to develop and adhere to strict research methodologies that are evidence-based instead of preconceived notions of a particular social issue. 5

Action Research and Participatory-Action Research (PAR)

By emphasizing the importance of direct collaboration with communities, researchers can hope to identify and address a demographic’s needs. 6

Empowerment Research

Studies, surveys and experiments aim to increase the feelings of empowerment, equality and social justice among people in communities by having them participate directly in the research process. 7

Constructivist Research

Constructivist research begins with the individual and their social contexts instead of the community as a whole. 8 It highlights the importance of perspective and social standing in shaping communities .

Designing Effective Evaluation Frameworks for Social Programs

Data collected from participants in a target demographic is considered raw data that needs to go through several stages of cleaning and refining before any insights can be extracted. 9 That’s why researchers need to be able to develop robust evaluation frameworks that facilitate access to the data.

Logic Models

Logic models are often used to evaluate a single program or intervention. 10 Logic models are designed to offer:

• Development approaches: Using forward logic to develop models starts from activities to predict outcomes, or vice versa in the case of reverse logic
• Framework utility: Frameworks guide the implementation and reporting of the logic model by clarifying its methodology and expected results
• Visual representation: Graphical depictions of data illustrate the connections between a study’s input, activities and outputs, showcasing the anticipated outcomes
• Components: Key elements include the problem statement, outcomes, outputs, resources and strategies

Theories of Change and Program Theory

Merging theories with logic models adds depth to frameworks by outlining the research process, mechanisms and the logic behind the expected outcomes. 11 Furthermore, theories explain the “how” and “why” the desired changes and outcomes are expected to occur in the program’s context, including factors outside the program’s control.

Furthermore, leveraging resources such as The Kellogg Foundation Logic Model Development Guide and the CDC Framework for Program Evaluation in Social Work can offer guidance and tools for constructing and utilizing robust evaluation frameworks. 12,13

Data Collection and Analysis Techniques in Social Work Research

Researchers can collect relevant data in a variety of ways , such as surveys, in-person focus groups, observations and official census reports. They can then select the suitable social work data analysis technique based on the type of data they have and the nature of the insights they’re looking for. 14 These techniques include:

• Thematic analysis: A qualitative approach that identifies, analyzes and reports patterns and anomalies
• Descriptive statistics: Mean, medians, modes and averages of datasets
• Inferential statistics: Predictive models that provide insights based on patterns

Ethical Considerations in Social Work Research and Evaluation

Ethical considerations determine the efficacy of social work research methods and evaluations. 15 Participants in the study must give informed consent to the data being collected on them without attempts to persuade or influence their answers. 16 Similarly, confidentiality and anonymity, especially when handling socially sensitive topics, are needed to ensure candid responses from study participants.

Utilizing Research Findings to Inform Evidence-Based Practice

In order to use results from past studies to inform future practices, researchers need to translate the studies’ outcomes through systematic reviews and guideline development. 17 The outcomes of earlier implementations often require constant monitoring to detect any underlying biases that can be addressed early on.

Challenges and Limitations in Social Work Research and Evaluation

Research in social work often faces numerous challenges that might impact the quality and efficacy of studies. Some of the most common ones include:

• Time constraints
• Hard-to-reach populations
• Inadequate strategies
• Financial constraints

Case Study of Successful Research and Evaluation Initiative

Despite the many complexities, many research studies can be successfully conducted in the field of social studies. One example is the study of developing new treatments for post-traumatic stress disorder (PTSD) patients.

First developed in the 1980s by Francine Shapiro, eye movement desensitization and reprocessing has been successful in treating emotional distress associated with PTSD. The method’s application was then expanded to include a wide range of issues from trauma and anxiety to addiction.

It’s been supported by over 30 controlled outcomes studies and has since been recognized by the World Health Organization and the Department of Veterans Affairs (VA) as an effective therapeutic method. 18

Deepen Your Impact Through Social Work

The intersection between theoretical research and practical evaluation in the field of social work produces solutions that make a profound impact on the quality of life of communities and individuals. 19 This is a testament to the commitment of researchers to advance the field through progressively available means, particularly technology for data collection and mathematical algorithms for Big Data analytics.

Yeshiva University’s online Master of Social Work focuses on cultural responsiveness, social justice, and human transformation. You will gain hands-on experience in the field of social work and obtain CSWE accreditation that qualifies you for the post-graduate state exam. The expert faculty will equip you with the tools to create positive change in the world. Make an appointment to speak with an admissions outreach advisor today.

• Retrieved on April 10, 2024, from hbr.org/podcast/2021/01/using-behavioral-science-to-improve-well-being-for-social-workers
• Retrieved on April 10, 2024, from researchgate.net/publication/323370072_Evaluating_effectiveness_in_social_work_sharing_dilemmas_in_practice
• Retrieved on April 10, 2024, from ncbi.nlm.nih.gov/books/NBK547524/
• Retrieved on April 10, 2024, from researchgate.net/publication/298697140_Big_data_in_social_work_The_development_of_a_critical_perspective_on_social_work’s_latest_electronic_turn
• Retrieved on April 10, 2024, from https://caseworthy.com/articles/why-is-evidence-based-practice-important-in-social-work/
• Retrieved on April 10, 2024, from nature.com/articles/s43586-023-00214-1
• Retrieved on April 10, 2024, from academic.oup.com/bjsw/article/51/4/1482/6202975
• Retrieved on April 10, 2024, from journals.sagepub.com/doi/full/10.1177/16094069231186257
• Retrieved on April 10, 2024, from journals.sagepub.com/doi/10.1177/17456916221137350
• Retrieved on April 10, 2024, from sopact.com/guides/theory-of-change-vs-logic-model
• Retrieved on April 10, 2024, from betterevaluation.org/frameworks-guides/rainbow-framework/define/develop-programme-theory-theory-change
• Retrieved on April 10, 2024, from naccho.org/uploads/downloadable-resources/Programs/Public-Health-Infrastructure/KelloggLogicModelGuide_161122_162808.pdffrom-being-a-breeding-ground-for-threats/
• Retrieved on April 10, 2024, from cdc.gov/evaluation/framework/index.htm
• Retrieved on April 10, 2024, from nesta.org.uk/feature/eight-ways-councils-are-using-data-create-better-services/the-data-driven-social-worker/
• Retrieved on April 10, 2024, from cmsindia.org/sites/myfiles/Guidelines-for-Ethical-Considerations-in-Social-Research-Evaluation-In-India_2020.pdf
• Retrieved on April 10, 2024, from researchsupport.admin.ox.ac.uk/governance/ethics/resources/consent
• Retrieved on April 10, 2024, from health-policy-systems.biomedcentral.com/articles/10.1186/s12961-020-00662-1
• Retrieved on April 10, 2024, from ptsd.va.gov/understand_tx/emdr.asp
• Retrieved on April 10, 2024, from researchgate.net/publication/8480043_Future_directions_in_evaluation_research_People_organizational_and_social_issues

Return to Blog

Yeshiva University has engaged Everspring , a leading provider of education and technology services, to support select aspects of program delivery.

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

• View all journals
• Explore content
• About the journal
• Publish with us
• Sign up for alerts
• Published: 06 May 2024

APOE4 homozygozity represents a distinct genetic form of Alzheimer’s disease

• Juan Fortea   ORCID: orcid.org/0000-0002-1340-638X 1 , 2 , 3   na1 ,
• Jordi Pegueroles   ORCID: orcid.org/0000-0002-3554-2446 1 , 2 ,
• Daniel Alcolea   ORCID: orcid.org/0000-0002-3819-3245 1 , 2 ,
• Olivia Belbin   ORCID: orcid.org/0000-0002-6109-6371 1 , 2 ,
• Oriol Dols-Icardo   ORCID: orcid.org/0000-0003-2656-8748 1 , 2 ,
• Lídia Vaqué-Alcázar 1 , 4 ,
• Laura Videla   ORCID: orcid.org/0000-0002-9748-8465 1 , 2 , 3 ,
• Juan Domingo Gispert 5 , 6 , 7 , 8 , 9 ,
• Marc Suárez-Calvet   ORCID: orcid.org/0000-0002-2993-569X 5 , 6 , 7 , 8 , 9 ,
• Sterling C. Johnson   ORCID: orcid.org/0000-0002-8501-545X 10 ,
• Reisa Sperling   ORCID: orcid.org/0000-0003-1535-6133 11 ,
• Alexandre Bejanin   ORCID: orcid.org/0000-0002-9958-0951 1 , 2 ,
• Alberto Lleó   ORCID: orcid.org/0000-0002-2568-5478 1 , 2 &
• Víctor Montal   ORCID: orcid.org/0000-0002-5714-9282 1 , 2 , 12   na1  

Nature Medicine ( 2024 ) Cite this article

10k Accesses

4065 Altmetric

Metrics details

• Alzheimer's disease
• Predictive markers

This study aimed to evaluate the impact of APOE4 homozygosity on Alzheimer’s disease (AD) by examining its clinical, pathological and biomarker changes to see whether APOE4 homozygotes constitute a distinct, genetically determined form of AD. Data from the National Alzheimer’s Coordinating Center and five large cohorts with AD biomarkers were analyzed. The analysis included 3,297 individuals for the pathological study and 10,039 for the clinical study. Findings revealed that almost all APOE4 homozygotes exhibited AD pathology and had significantly higher levels of AD biomarkers from age 55 compared to APOE3 homozygotes. By age 65, nearly all had abnormal amyloid levels in cerebrospinal fluid, and 75% had positive amyloid scans, with the prevalence of these markers increasing with age, indicating near-full penetrance of AD biology in APOE4 homozygotes. The age of symptom onset was earlier in APOE4 homozygotes at 65.1, with a narrower 95% prediction interval than APOE3 homozygotes. The predictability of symptom onset and the sequence of biomarker changes in APOE4 homozygotes mirrored those in autosomal dominant AD and Down syndrome. However, in the dementia stage, there were no differences in amyloid or tau positron emission tomography across haplotypes, despite earlier clinical and biomarker changes. The study concludes that APOE4 homozygotes represent a genetic form of AD, suggesting the need for individualized prevention strategies, clinical trials and treatments.

This is a preview of subscription content, access via your institution

Access options

Access Nature and 54 other Nature Portfolio journals

Get Nature+, our best-value online-access subscription

24,99 € / 30 days

cancel any time

Subscribe to this journal

Receive 12 print issues and online access

195,33 € per year

only 16,28 € per issue

Buy this article

• Purchase on Springer Link
• Instant access to full article PDF

Prices may be subject to local taxes which are calculated during checkout

Similar content being viewed by others

Exceptionally low likelihood of Alzheimer’s dementia in APOE2 homozygotes from a 5,000-person neuropathological study

Association of APOE e2 genotype with Alzheimer’s and non-Alzheimer’s neurodegenerative pathologies

Apolipoprotein E and Alzheimer disease: pathobiology and targeting strategies

Data availability.

Access to tabular data from ADNI ( https://adni.loni.usc.edu/ ), OASIS ( https://oasis-brains.org/ ), A4 ( https://ida.loni.usc.edu/collaboration/access/appLicense.jsp ) and NACC ( https://naccdata.org/ ) can be requested online, as publicly available databases. All requests will be reviewed by each studyʼs scientific board. Concrete inquiries to access the WRAP ( https://wrap.wisc.edu/data-requests-2/ ) and ALFA + ( https://www.barcelonabeta.org/en/alfa-study/about-the-alfa-study ) cohort data can be directed to each study team for concept approval and feasibility consultation. Requests will be reviewed to verify whether the request is subject to any intellectual property.

Code availability

All statistical analyses and raw figures were generated using R (v.4.2.2). We used the open-sourced R packages of ggplot2 (v.3.4.3), dplyr (v.1.1.3), ggstream (v.0.1.0), ggpubr (v.0.6), ggstatsplot (v.0.12), Rmisc (v.1.5.1), survival (v.3.5), survminer (v.0.4.9), gtsummary (v.1.7), epitools (v.0.5) and statsExpression (v.1.5.1). Rscripts to replicate our findings can be found at https://gitlab.com/vmontalb/apoe4-asdad (ref. 32 ). For neuroimaging analyses, we used Free Surfer (v.6.0) and ANTs (v.2.4.0).

Bellenguez, C. et al. New insights into the genetic etiology of Alzheimer’s disease and related dementias. Nat. Genet. 54 , 412–436 (2022).

Article   CAS   PubMed   PubMed Central   Google Scholar  

Frisoni, G. B. et al. The probabilistic model of Alzheimer disease: the amyloid hypothesis revised. Nat. Rev. Neurosci. 23 , 53–66 (2022).

Article   CAS   PubMed   Google Scholar  

Bateman R. J. et al. Clinical and biomarker changes in dominantly inherited Alzheimer’s disease. N. Engl. J. Med. 367 , 795–804 (2012).

Genin, E. et al. APOE and Alzheimer disease: a major gene with semidominant inheritance. Mol. Psychiatry 16 , 903–907 (2011).

Fortea, J. et al. Alzheimer’s disease associated with Down syndrome: a genetic form of dementia. Lancet Neurol. 20 , 930–942 (2021).

Fortea, J. et al. Clinical and biomarker changes of Alzheimer’s disease in adults with Down syndrome: a cross-sectional study. Lancet 395 , 1988–1997 (2020).

Jansen, W. J. et al. Prevalence of cerebral amyloid pathology in persons without dementia: a meta-analysis. JAMA 313 , 1924–1938 (2015).

Article   PubMed   PubMed Central   Google Scholar  

Saddiki H. et al. Age and the association between apolipoprotein E genotype and Alzheimer disease: a cerebrospinal fluid biomarker-based case-control study. PLoS Med. https://doi.org/10.1371/JOURNAL.PMED.1003289 (2020).

Jack, C. R. et al. NIA‐AA Research Framework: toward a biological definition of Alzheimer’s disease. Alzheimer’s Dement. 14 , 535–562 (2018).

Article   Google Scholar  

Beekly, D. L. et al. The National Alzheimer’s Coordinating Center (NACC) Database: an Alzheimer disease database. Alzheimer Dis. Assoc. Disord. 18 , 270–277 (2004).

PubMed   Google Scholar  

Montine, T. J. et al. National Institute on Aging–Alzheimer’s Association guidelines for the neuropathologic assessment of Alzheimer’s disease: a practical approach. Acta Neuropathol. 123 , 1–11 (2012).

Reiman, E. M. et al. Exceptionally low likelihood of Alzheimer’s dementia in APOE2 homozygotes from a 5,000-person neuropathological study. Nat. Commun. 11 , 1–11 (2020).

Iulita M. F. et al. Association of Alzheimer disease with life expectancy in people with Down syndrome. JAMA Netw. Open https://doi.org/10.1001/JAMANETWORKOPEN.2022.12910 (2022).

Corder, E. H. et al. Gene dose of apolipoprotein E type 4 allele and the risk of Alzheimer’s disease in late onset families. Science 261 , 921–923 (1993).

Fortea, J., Quiroz, Y. T. & Ryan, N. S. Lessons from Down syndrome and autosomal dominant Alzheimer’s disease. Lancet Neurol. 22 , 5–6 (2023).

Therriault, J. et al. Frequency of biologically defined Alzheimer’s disease in relation to age, sex, APOE ε4, and cognitive impairment. Neurology 96 , e975–e985 (2021).

Betthauser, T. J. et al. Multi-method investigation of factors influencing amyloid onset and impairment in three cohorts. Brain 145 , 4065–4079 (2022).

Snellman, A. et al. APOE ε4 gene dose effect on imaging and blood biomarkers of neuroinflammation and beta-amyloid in cognitively unimpaired elderly. Alzheimers Res. Ther. 15 , 71 (2023).

Ghisays, V. et al. Brain imaging measurements of fibrillar amyloid-β burden, paired helical filament tau burden, and atrophy in cognitively unimpaired persons with two, one, and no copies of the APOE ε4 allele. Alzheimers Dement. 16 , 598–609 (2020).

Mehta, R. I. & Schneider, J. A. What is ‘Alzheimer’s disease’? The neuropathological heterogeneity of clinically defined Alzheimer’s dementia. Curr. Opin. Neurol. 34 , 237–245 (2021).

van der Lee, S. J. et al. The effect of APOE and other common genetic variants on the onset of Alzheimer’s disease and dementia: a community-based cohort study. Lancet Neurol. 17 , 434–444 (2018).

Belloy, M. E., Napolioni, V. & Greicius, M. D. A quarter century of APOE and Alzheimera’s disease: progress to date and the path forward. Neuron 101 , 820–838 (2019).

Belloy, M. E. et al. APOE genotype and Alzheimer disease risk across age, sex, and population ancestry. JAMA Neurol. 80 , 1284–1294 (2023).

Jack, C. R. et al. Long-term associations between amyloid positron emission tomography, sex, apolipoprotein E and incident dementia and mortality among individuals without dementia: hazard ratios and absolute risk. Brain Commun. 4 , fcac017 (2022).

Morris, J. C. The Clinical Dementia Rating (CDR): current version and scoring rules. Neurology 43 , 2412–2414 (1993).

Weiner, M. W. et al. The Alzheimer’s Disease Neuroimaging Initiative 3: continued innovation for clinical trial improvement. Alzheimer’s Dement. 13 , 561–571 (2017).

Sperling R. A. et al. The A4 Study: stopping AD before symptoms begin? Sci. Transl. Med. https://doi.org/10.1126/scitranslmed.3007941 (2014).

Molinuevo, J. L. et al. The ALFA project: a research platform to identify early pathophysiological features of Alzheimer’s disease. Alzheimer’s Dement.: Transl. Res. Clin. Interventions 2 , 82–92 (2016).

Johnson, S. C. et al. The Wisconsin Registry for Alzheimer’s Prevention: a review of findings and current directions. Alzheimer’s Dement.: Diagnosis, Assess. Dis. Monit. 10 , 130–142 (2018).

Google Scholar  

LaMontagne P. J. et al. OASIS-3: longitudinal neuroimaging, clinical and cognitive dataset for normal aging and Alzheimer disease. Preprint at MedRxiv https://doi.org/10.1101/2019.12.13.19014902 (2019).

La Joie, R. et al. Multisite study of the relationships between antemortem [ 11 C]PIB-PET Centiloid values and postmortem measures of Alzheimer’s disease neuropathology. Alzheimers Dement. 15 , 205–216 (2019).

Montal, V. APOE4-ASDAD. GitLab https://gitlab.com/vmontalb/apoe4-asdad (2024).

Download references

Acknowledgements

We acknowledge the contributions of several consortia that provided data for this study. We extend our appreciation to the NACC, the Alzheimer’s Disease Neuroimaging Initiative, The A4 Study, the ALFA Study, the Wisconsin Register for Alzheimer’s Prevention and the OASIS3 Project. Without their dedication to advancing Alzheimer’s disease research and their commitment to data sharing, this study would not have been possible. We also thank all the participants and investigators involved in these consortia for their tireless efforts and invaluable contributions to the field. We also thank the institutions that funded this study, the Fondo de Investigaciones Sanitario, Carlos III Health Institute, the Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas and the Generalitat de Catalunya and La Caixa Foundation, as well as the NIH, Horizon 2020 and the Alzheimer’s Association, which was crucial for this research. Funding: National Institute on Aging. This study was supported by the Fondo de Investigaciones Sanitario, Carlos III Health Institute (INT21/00073, PI20/01473 and PI23/01786 to J.F., CP20/00038, PI22/00307 to A.B., PI22/00456 to M.S.-C., PI18/00435 to D.A., PI20/01330 to A.L.) and the Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas Program 1, partly jointly funded by Fondo Europeo de Desarrollo Regional, Unión Europea, Una Manera de Hacer Europa. This work was also supported by the National Institutes of Health grants (R01 AG056850; R21 AG056974, R01 AG061566, R01 AG081394 and R61AG066543 to J.F., S10 OD025245, P30 AG062715, U54 HD090256, UL1 TR002373, P01 AG036694 and P50 AG005134 to R.S.; R01 AG027161, R01 AG021155, R01 AG037639, R01 AG054059; P50 AG033514 and P30 AG062715 to S.J.) and ADNI (U01 AG024904), the Department de Salut de la Generalitat de Catalunya, Pla Estratègic de Recerca I Innovació en Salut (SLT006/17/00119 to J.F.; SLT002/16/00408 to A.L.) and the A4 Study (R01 AG063689, U24 AG057437 to R.A.S). It was also supported by Fundación Tatiana Pérez de Guzmán el Bueno (IIBSP-DOW-2020-151 o J.F.) and Horizon 2020–Research and Innovation Framework Programme from the European Union (H2020-SC1-BHC-2018-2020 to J.F.; 948677 and 847648 to M.S.-C.). La Caixa Foundation (LCF/PR/GN17/50300004 to M.S.-C.) and EIT Digital (Grant 2021 to J.D.G.) also supported this work. The Alzheimer Association also participated in the funding of this work (AARG-22-923680 to A.B.) and A4/LEARN Study AA15-338729 to R.A.S.). O.D.-I. receives funding from the Alzheimer’s Association (AARF-22-924456) and the Jerome Lejeune Foundation postdoctoral fellowship.

Author information

These authors contributed equally: Juan Fortea, Víctor Montal.

Authors and Affiliations

Sant Pau Memory Unit, Hospital de la Santa Creu i Sant Pau - Biomedical Research Institute Sant Pau, Barcelona, Spain

Juan Fortea, Jordi Pegueroles, Daniel Alcolea, Olivia Belbin, Oriol Dols-Icardo, Lídia Vaqué-Alcázar, Laura Videla, Alexandre Bejanin, Alberto Lleó & Víctor Montal

Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas. CIBERNED, Barcelona, Spain

Juan Fortea, Jordi Pegueroles, Daniel Alcolea, Olivia Belbin, Oriol Dols-Icardo, Laura Videla, Alexandre Bejanin, Alberto Lleó & Víctor Montal

Barcelona Down Medical Center, Fundació Catalana Síndrome de Down, Barcelona, Spain

Juan Fortea & Laura Videla

Department of Medicine, Faculty of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, Barcelona, Spain

Lídia Vaqué-Alcázar

Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Barcelona, Spain

Juan Domingo Gispert & Marc Suárez-Calvet

Neurosciences Programme, IMIM - Hospital del Mar Medical Research Institute, Barcelona, Spain

Department of Medicine and Life Sciences, Universitat Pompeu Fabra, Barcelona, Spain

Centro de Investigación Biomédica en Red Bioingeniería, Biomateriales y Nanomedicina. Instituto de Salud carlos III, Madrid, Spain

Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain

Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA

Sterling C. Johnson

Brigham and Women’s Hospital Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA

Reisa Sperling

Barcelona Supercomputing Center, Barcelona, Spain

Víctor Montal

You can also search for this author in PubMed   Google Scholar

Contributions

J.F. and V.M. conceptualized the research project and drafted the initial manuscript. V.M., J.P. and J.F. conducted data analysis, interpreted statistical findings and created visual representations of the data. O.B. and O.D.-I. provided valuable insights into the genetics of APOE. L.V., A.B. and L.V.-A. meticulously reviewed and edited the manuscript for clarity, accuracy and coherence. J.D.G., M.S.-C., S.J. and R.S. played pivotal roles in data acquisition and securing funding. A.L. and D.A. contributed to the study design, offering guidance and feedback on statistical analyses, and provided critical review of the paper. All authors carefully reviewed the manuscript, offering pertinent feedback that enhanced the study’s quality, and ultimately approved the final version.

Corresponding authors

Correspondence to Juan Fortea or Víctor Montal .

Ethics declarations

Competing interests.

S.C.J. has served at scientific advisory boards for ALZPath, Enigma and Roche Diagnostics. M.S.-C. has given lectures in symposia sponsored by Almirall, Eli Lilly, Novo Nordisk, Roche Diagnostics and Roche Farma, received consultancy fees (paid to the institution) from Roche Diagnostics and served on advisory boards of Roche Diagnostics and Grifols. He was granted a project and is a site investigator of a clinical trial (funded to the institution) by Roche Diagnostics. In-kind support for research (to the institution) was received from ADx Neurosciences, Alamar Biosciences, Avid Radiopharmaceuticals, Eli Lilly, Fujirebio, Janssen Research & Development and Roche Diagnostics. J.D.G. has served as consultant for Roche Diagnostics, receives research funding from Hoffmann–La Roche, Roche Diagnostics and GE Healthcare, has given lectures in symposia sponsored by Biogen, Philips Nederlands, Esteve and Life Molecular Imaging and serves on an advisory board for Prothena Biosciences. R.S. has received personal consulting fees from Abbvie, AC Immune, Acumen, Alector, Bristol Myers Squibb, Janssen, Genentech, Ionis and Vaxxinity outside the submitted work. O.B. reported receiving personal fees from Adx NeuroSciences outside the submitted work. D.A. reported receiving personal fees for advisory board services and/or speaker honoraria from Fujirebio-Europe, Roche, Nutricia, Krka Farmacéutica and Esteve, outside the submitted work. A.L. has served as a consultant or on advisory boards for Almirall, Fujirebio-Europe, Grifols, Eisai, Lilly, Novartis, Roche, Biogen and Nutricia, outside the submitted work. J.F. reported receiving personal fees for service on the advisory boards, adjudication committees or speaker honoraria from AC Immune, Adamed, Alzheon, Biogen, Eisai, Esteve, Fujirebio, Ionis, Laboratorios Carnot, Life Molecular Imaging, Lilly, Lundbeck, Perha, Roche and outside the submitted work. O.B., D.A., A.L. and J.F. report holding a patent for markers of synaptopathy in neurodegenerative disease (licensed to Adx, EPI8382175.0). The remaining authors declare no competing interests.

Peer review

Peer review information.

Nature Medicine thanks Naoyuki Sato, Yadong Huang and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Primary Handling Editor: Jerome Staal, in collaboration with the Nature Medicine team.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary information.

Supplementary Methods, Results, Bibliography, Figs. 1–7 and Tables 1–3.

Reporting Summary

Supplementary code.

This code is also available in the GitLab repository.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Cite this article.

Fortea, J., Pegueroles, J., Alcolea, D. et al. APOE4 homozygozity represents a distinct genetic form of Alzheimer’s disease. Nat Med (2024). https://doi.org/10.1038/s41591-024-02931-w

Download citation

Received : 03 November 2023

Accepted : 19 March 2024

Published : 06 May 2024

DOI : https://doi.org/10.1038/s41591-024-02931-w

Share this article

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

Quick links

• Explore articles by subject
• Guide to authors
• Editorial policies

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Our websites may use cookies to personalize and enhance your experience. By continuing without changing your cookie settings, you agree to this collection. For more information, please see our University Websites Privacy Notice .

Office of Undergraduate Research

Work-study research assistant program – faculty.

• Program Information
• Opportunities

Program Overview

The Work-Study Research Assistant Program is designed to help students with financial need develop research skills and explore their academic interests. Research experiences develop transferable skills and can change the course of a student’s academic and/or professional career. Our expectation is that the research assistant will be substantively engaged in a faculty member’s research endeavors. These positions are not to be exclusively clerical or lab upkeep positions.

Prospective Faculty Participants

Key program details.

• The goal of this program is to help students develop research skills and interests. Research experiences develop transferable skills and can change the course of a student’s academic and/or professional career. Our expectation is that the research assistant will be substantively engaged in your research - these are not to be exclusively clerical or lab upkeep positions.
• The typical work-study research assistant would work approximately 90-100 hours (an average of 6-7 hours per week) in both the fall semester AND the spring semester. These numbers are based on the typical work-study award amount and the pay rate for the research positions we envision. We can provide exact numbers once you have selected a student to hire.
• The distribution of the hours of work is flexible within each semester , with the ability to roll hours forward from fall to spring, but not beyond the final day for 2023-24 work-study (early May 2024, date TBD). However, it is expected that the workload will take the student’s academic schedule into consideration and be predictable from week to week. An even distribution of hours would be approximately 6 hours per week during regular classes. If you are interested in participating in the program, it is important to ensure that you will have 6 hours/week of appropriate tasks for your research assistant.
• Work-study and the university will pay 100% of the student’s wages up to the dollar limit of their awards (e.g., $3,000 for the academic year). If you wish to continue to pay the student for additional work (and their schedule permits), you would be responsible for 100% of the wages, and would need to make the relevant payroll arrangements with your department, in consultation with us.
• You have control over the hiring process. You edit the job advertisement, you review the candidates, you interview the candidates, and you choose to hire the research assistant. The only constraint is that the student must have a 2023-24 work-study award. Once you submit a detailed advertisement for your job via the online form, OUR will post the job, collect the applications, and forward all of the eligible applicants to you for review.
• Review the Guidelines for Faculty Posting a Research Assistant Position .
• Student Equipment Design & Testing Assistant (201)
• Student Interview & Survey Research Assistant (202)
• Student Laboratory & Field Analysis Assistant (203)
• Student Human Behavioral Research Assistant (204)
• Student Research Review Assistant (205)
• Complete the online submission form to include the specific duties you expect the assistant to execute, the qualifications s/he must have, and the application materials you wish to receive. Note that students awarded Federal Work-Study are actively seeking jobs over the summer and we prefer to post the positions as early as possible. Jodi Eskin will submit your job description to Student Employment for approval and be in touch once the position is open on the JobX employment site. No opportunities will be accepted for posting after August 7, 2023.
• Review the applications sent to you by OUR, conduct interviews of finalists (phone or virtual platforms are fine), and inform OUR of your choice of research assistant.
• Complete the EHS/OUR Safety Confirmation form for each student you hire. If appropriate, add your research assistant to your group in the new HuskySMS training platform and note the required job activities in order to generate the student's list of required safety training courses. Follow up, as needed, to confirm that the student has completed any required COVID/safety training courses.
• Discuss your expectations with the research assistant and supervise his/her work.
• Provide feedback to your student on an ongoing basis. Take time to conduct a formal evaluation of the student's work as evaluations play a critical role in a student's learning.
• Regularly review a time-tracking spreadsheet to ensure your assistant's work hours are reported accurately. Note that all payroll and timekeeping processes will be managed by OUR staff - these will not be the responsibility of your departmental staff.
• Submit a brief report on your assistant’s work by December 20, 2023 and May 15, 2024 . Feedback from faculty on how the program is working is essential to the development and modification of this program for future years.

• Skip to main content
• Keyboard shortcuts for audio player

• Your Health
• Treatments & Tests
• Health Inc.
• Public Health

Scientists welcome new rules on marijuana, but research will still face obstacles

Rhitu Chatterjee

For decades, researchers in the U.S. had to use only marijuana grown at a facility located in Oxford, Mississippi. A few other approved growers have been added in recent years. Brad Horrigan/Hartford Courant/Tribune News Service via Getty Images hide caption

For decades, researchers in the U.S. had to use only marijuana grown at a facility located in Oxford, Mississippi. A few other approved growers have been added in recent years.

As the Biden administration moves to reclassify marijuana as a less dangerous drug, scientists say the change will lift some of the restrictions on studying the drug.

But the change won't lift all restrictions, they say, neither will it decrease potential risks of the drug or help users better understand what those risks are.

Marijuana is currently classified as a Schedule I controlled substance , which is defined as a substance with no accepted medical use and a high potential for abuse. The Biden administration proposed this week to classify cannabis as a Schedule III controlled substance, a category that acknowledges it has some medical benefits.

The current Schedule I status imposes many regulations and restrictions on scientists' ability to study weed, even as state laws have made it increasingly available to the public.

"Cannabis as a Schedule I substance is associated with a number of very, very restrictive regulations," says neuroscientist Staci Gruber at McLean Hospital and Harvard Medical School. "You have very stringent requirements, for example, for storage and security and reporting all of these things."

These requirements are set by the Food and Drug Administration, the Drug Enforcement Administration, the Institutional Review Board and local authorities, she says. Scientists interested in studying the drug also have to register with the DEA and get a state and federal license to conduct research on the drug.

"It's a burdensome process and it is certainly a process that has prevented a number of young and rather invested researchers from pursuing [this kind of work]," says Gruber.

Reclassifying the drug as Schedule III puts it in the same category as ketamine and Tylenol with codeine. Substances in this category have accepted medical use in the United States, have less potential for abuse than in higher categories and abuse could lead to low to moderate levels of dependence on the drug.

This reclassification is "a very, very big paradigm shift," says Gruber. "I think that has a big trickle down effect in terms of the perspectives and the attitudes with regard to the actual sort of differences between studying Schedule III versus Schedule I substances."

Gruber welcomes the change, particularly for what it will mean for younger colleagues. "For researchers who are looking to get into the game, it will be easier. You don't have to have a Schedule I license," she says. "That's a big deal."

The rescheduling of cannabis will also "translate to more research on the benefits and risks of cannabis for the treatment of medical conditions," writes Dr. Andrew Monte in an email. He is associate director of Rocky Mountain Poison and Drug Safety and an emergency physician and toxicologist at the University of Colorado School of Medicine.

"This will also help improve the quality of the research since more researchers will be able to contribute," he adds.

Senate Democrats hold a press conference on Wednesday pitching new, less strict marijuana laws. From left are Senators Cory Booker of N.J., Majority Leader Chuck Schumer of N.Y., and Ron Wyden of Oregon. Tom Williams/CQ-Roll Call, Inc via Getty Imag hide caption

Senate Democrats hold a press conference on Wednesday pitching new, less strict marijuana laws. From left are Senators Cory Booker of N.J., Majority Leader Chuck Schumer of N.Y., and Ron Wyden of Oregon.

But the change in classification won't significantly expand the number of sources for the drug for researchers, says Gruber. For 50 years, researchers were allowed to use cannabis from only one source – a facility at the University of Mississippi. Then, in 2021, the DEA started to add a few more companies to that list of approved sources for medical and scientific research.

While she expects more sources to be added in time, she and many of the researchers she knows have yet to benefit from the recently added sources, as most have limited products available.

"And what we haven't seen is any ability for researchers –cannabis researchers, clinical researchers – to have the ability to study products that our patients and our recreational consumers or adult consumers are actually using," she adds. "That remains impossible."

Shots - Health News

Rare and mysterious vomiting illness linked to heavy marijuana use.

There is very little known information about what is in cannabis products on the market today. Some studies show that the level of THC, the main intoxicant in marijuana, being sold to consumers today is significantly higher than what was available decades ago, and high THC levels are known to pose more health risks.

And Monte cautions that the reclassification itself doesn't mean that cannabis has no health risks. Monte and his colleagues have been documenting some of those risks in Colorado by studying people who show up in the emergency room after consuming cannabis. Intoxication and cyclical vomiting ( cannabinoid hyperemesis syndrome ) and alarming psychiatric symptoms such as psychosis are among the top problems bringing some marijuana users to the hospital.

Research on cannabis has been lacking surveillance of these kinds of impacts for decades, he says. And rescheduling the drug will not fill that "gaping hole in risk surveillance," he writes.

• drug policy
• legal marijuana
• Scientific research
• biden administration

Watch CBS News

Limit these ultra-processed foods for longer-term health, 30-year study suggests

By Sara Moniuszko

Edited By Paula Cohen

Updated on: May 10, 2024 / 11:09 AM EDT / CBS News

New research is adding to the evidence linking  ultra-processed foods  to health concerns. The study tracked people's habits over 30 years and found those who reported eating more of certain ultra-processed foods had a slightly higher risk of death — with four categories of foods found to be the biggest culprits. 

For the study, published in The BMJ , researchers analyzed data on more than 100,000 U.S. adults with no history of cancer, cardiovascular disease or diabetes. Every four years between 1986 and 2018, the participants completed a detailed food questionnaire.

The data showed those who ate the most  ultra-processed food — about 7 servings per day — had a 4% higher risk of death by any cause, compared to participants who ate the lowest amount, a median of about 3 servings per day.

Ultra-processed foods include "packaged baked goods and snacks, fizzy drinks, sugary cereals, and ready-to-eat or heat products,"  a news release  for the study noted. "They often contain colors, emulsifiers, flavors, and other additives and are typically high in energy, added sugar, saturated fat, and salt, but lack vitamins and fiber."

Foods with the strongest associations with increased mortality, according to the study, included:

• Ready-to-eat meat, poultry and seafood-based products
• Sugary drinks
• Dairy-based desserts
• Highly processed breakfast foods

Ultra-processed food is a "very mixed group of very different foods," the lead author of the study, Mingyang Song,  told CBS News , meaning these categories can offer a helpful distinction. 

"Some of the foods actually have really beneficial ingredients like vitamins, minerals, so that's why we always recommend that people not focus too much on the (whole of) ultra-processed food, but rather the individual categories of ultra-processed food."

The research included a large number of participants over a long timespan, but it did have some limitations. As an observational study, no exact cause-and-effect conclusions can be drawn. And the participants were health professionals and predominantly White and non-Hispanic, "limiting the generalizability of our findings," the authors acknowledged.

But they wrote that the findings "provide support for limiting consumption of certain types of ultra-processed food for long term health." 

"Future studies are warranted to improve the classification of ultra-processed foods and confirm our findings in other populations," they added.

This study comes after other research published earlier this year found diets high in ultra-processed food are associated with an increased risk of 32 damaging health outcomes , including higher risk for cancer, major heart and lung conditions, gastrointestinal issues, obesity, type 2 diabetes, sleep issues, mental health disorders and early death.

Sara Moniuszko is a health and lifestyle reporter at CBSNews.com. Previously, she wrote for USA Today, where she was selected to help launch the newspaper's wellness vertical. She now covers breaking and trending news for CBS News' HealthWatch.

More from CBS News

"FLiRT" COVID variants are spreading. Scientists share what we know so far.

Lawmakers approve millions of dollars to address youth mental health crisis

Denver celebrates the opening of 49 new affordable condos in Five Points

Cadet program results from partnership between APD & community college

Thousands Believe Covid Vaccines Harmed Them. Is Anyone Listening?

All vaccines have at least occasional side effects. But people who say they were injured by Covid vaccines believe their cases have been ignored.

Shaun Barcavage, 54, a nurse practitioner in New York City, said that ever since his first Covid shot, standing up has sent his heart racing. Credit... Hannah Yoon for The New York Times

Supported by

• Share full article

By Apoorva Mandavilli

Apoorva Mandavilli spent more than a year talking to dozens of experts in vaccine science, policymakers and people who said they had experienced serious side effects after receiving a Covid-19 vaccine.

• Published May 3, 2024 Updated May 4, 2024

Within minutes of getting the Johnson & Johnson Covid-19 vaccine, Michelle Zimmerman felt pain racing from her left arm up to her ear and down to her fingertips. Within days, she was unbearably sensitive to light and struggled to remember simple facts.

She was 37, with a Ph.D. in neuroscience, and until then could ride her bicycle 20 miles, teach a dance class and give a lecture on artificial intelligence, all in the same day. Now, more than three years later, she lives with her parents. Eventually diagnosed with brain damage, she cannot work, drive or even stand for long periods of time.

“When I let myself think about the devastation of what this has done to my life, and how much I’ve lost, sometimes it feels even too hard to comprehend,” said Dr. Zimmerman, who believes her injury is due to a contaminated vaccine batch .

The Covid vaccines, a triumph of science and public health, are estimated to have prevented millions of hospitalizations and deaths . Yet even the best vaccines produce rare but serious side effects . And the Covid vaccines have been given to more than 270 million people in the United States, in nearly 677 million doses .

Dr. Zimmerman’s account is among the more harrowing, but thousands of Americans believe they suffered serious side effects following Covid vaccination. As of April, just over 13,000 vaccine-injury compensation claims have been filed with the federal government — but to little avail. Only 19 percent have been reviewed. Only 47 of those were deemed eligible for compensation, and only 12 have been paid out, at an average of about $3,600 .

Some scientists fear that patients with real injuries are being denied help and believe that more needs to be done to clarify the possible risks.

“At least long Covid has been somewhat recognized,” said Akiko Iwasaki, an immunologist and vaccine expert at Yale University. But people who say they have post-vaccination injuries are “just completely ignored and dismissed and gaslighted,” she added.

In interviews and email exchanges conducted over several months, federal health officials insisted that serious side effects were extremely rare and that their surveillance efforts were more than sufficient to detect patterns of adverse events.

“Hundreds of millions of people in the United States have safely received Covid vaccines under the most intense safety monitoring in U.S. history,” Jeff Nesbit, a spokesman for the Department of Health and Human Services, said in an emailed statement.

But in a recent interview, Dr. Janet Woodcock, a longtime leader of the Food and Drug Administration, who retired in February, said she believed that some recipients had experienced uncommon but “serious” and “life-changing” reactions beyond those described by federal agencies.

“I feel bad for those people,” said Dr. Woodcock, who became the F.D.A.’s acting commissioner in January 2021 as the vaccines were rolling out. “I believe their suffering should be acknowledged, that they have real problems, and they should be taken seriously.”

“I’m disappointed in myself,” she added. “I did a lot of things I feel very good about, but this is one of the few things I feel I just didn’t bring it home.”

Federal officials and independent scientists face a number of challenges in identifying potential vaccine side effects.

The nation’s fragmented health care system complicates detection of very rare side effects, a process that depends on an analysis of huge amounts of data. That’s a difficult task when a patient may be tested for Covid at Walgreens, get vaccinated at CVS, go to a local clinic for minor ailments and seek care at a hospital for serious conditions. Each place may rely on different health record systems.

There is no central repository of vaccine recipients, nor of medical records, and no easy to way to pool these data. Reports to the largest federal database of so-called adverse events can be made by anyone, about anything. It’s not even clear what officials should be looking for.

“I mean, you’re not going to find ‘brain fog’ in the medical record or claims data, and so then you’re not going to find” a signal that it may be linked to vaccination, Dr. Woodcock said. If such a side effect is not acknowledged by federal officials, “it’s because it doesn’t have a good research definition,” she added. “It isn’t, like, malevolence on their part.”

The government’s understaffed compensation fund has paid so little because it officially recognizes few side effects for Covid vaccines. And vaccine supporters, including federal officials, worry that even a whisper of possible side effects feeds into misinformation spread by a vitriolic anti-vaccine movement.

‘I’m Not Real’

Patients who believe they experienced serious side effects say they have received little support or acknowledgment.

Shaun Barcavage, 54, a nurse practitioner in New York City who has worked on clinical trials for H.I.V. and Covid, said that ever since his first Covid shot, merely standing up sent his heart racing — a symptom suggestive of postural orthostatic tachycardia syndrome , a neurological disorder that some studies have linked to both Covid and, much less often, vaccination .

He also experienced stinging pain in his eyes, mouth and genitals, which has abated, and tinnitus, which has not.

“I can’t get the government to help me,” Mr. Barcavage said of his fruitless pleas to federal agencies and elected representatives. “I am told I’m not real. I’m told I’m rare. I’m told I’m coincidence.”

Renee France, 49, a physical therapist in Seattle, developed Bell’s palsy — a form of facial paralysis, usually temporary — and a dramatic rash that neatly bisected her face. Bell’s palsy is a known side effect of other vaccines, and it has been linked to Covid vaccination in some studies.

But Dr. France said doctors were dismissive of any connection to the Covid vaccines. The rash, a bout of shingles, debilitated her for three weeks, so Dr. France reported it to federal databases twice.

“I thought for sure someone would reach out, but no one ever did,” she said.

Similar sentiments were echoed in interviews, conducted over more than a year, with 30 people who said they had been harmed by Covid shots. They described a variety of symptoms following vaccination, some neurological, some autoimmune, some cardiovascular.

All said they had been turned away by physicians, told their symptoms were psychosomatic, or labeled anti-vaccine by family and friends — despite the fact that they supported vaccines.

Even leading experts in vaccine science have run up against disbelief and ambivalence.

Dr. Gregory Poland, 68, editor in chief of the journal Vaccine, said that a loud whooshing sound in his ears had accompanied every moment since his first shot, but that his entreaties to colleagues at the Centers for Disease Control and Prevention to explore the phenomenon, tinnitus, had led nowhere.

He received polite responses to his many emails, but “I just don’t get any sense of movement,” he said.

“If they have done studies, those studies should be published,” Dr. Poland added. In despair that he might “never hear silence again,” he has sought solace in meditation and his religious faith.

Dr. Buddy Creech, 50, who led several Covid vaccine trials at Vanderbilt University, said his tinnitus and racing heart lasted about a week after each shot. “It’s very similar to what I experienced during acute Covid, back in March of 2020,” Dr. Creech said.

Research may ultimately find that most reported side effects are unrelated to the vaccine, he acknowledged. Many can be caused by Covid itself.

“Regardless, when our patients experience a side effect that may or may not be related to the vaccine, we owe it to them to investigate that as completely as we can,” Dr. Creech said.

Federal health officials say they do not believe that the Covid vaccines caused the illnesses described by patients like Mr. Barcavage, Dr. Zimmerman and Dr. France. The vaccines may cause transient reactions, such as swelling, fatigue and fever, according to the C.D.C., but the agency has documented only four serious but rare side effects .

Two are associated with the Johnson & Johnson vaccine, which is no longer available in the United States: Guillain-Barré syndrome , a known side effect of other vaccines , including the flu shot; and a blood-clotting disorder.

The C.D.C. also links mRNA vaccines made by Pfizer-BioNTech and Moderna to heart inflammation, or myocarditis, especially in boys and young men. And the agency warns of anaphylaxis, or severe allergic reaction, which can occur after any vaccination.

Listening for Signals

Agency scientists are monitoring large databases containing medical information on millions of Americans for patterns that might suggest a hitherto unknown side effect of vaccination, said Dr. Demetre Daskalakis, director of the C.D.C.’s National Center for Immunization and Respiratory Diseases.

“We toe the line by reporting the signals that we think are real signals and reporting them as soon as we identify them as signals,” he said. The agency’s systems for monitoring vaccine safety are “pretty close” to ideal, he said.

Those national surveillance efforts include the Vaccine Adverse Event Reporting System (VAERS). It is the largest database, but also the least reliable: Reports of side effects can be submitted by anyone and are not vetted, so they may be subject to bias or manipulation.

The system contains roughly one million reports regarding Covid vaccination, the vast majority for mild events, according to the C.D.C.

Federal researchers also comb through databases that combine electronic health records and insurance claims on tens of millions of Americans. The scientists monitor the data for 23 conditions that may occur following Covid vaccination. Officials remain alert to others that may pop up, Dr. Daskalakis said.

But there are gaps, some experts noted. The Covid shots administered at mass vaccination sites were not recorded in insurance claims databases, for example, and medical records in the United States are not centralized.

“It’s harder to see signals when you have so many people, and things are happening in different parts of the country, and they’re not all collected in the same system,” said Rebecca Chandler, a vaccine safety expert at the Coalition for Epidemic Preparedness Innovations.

An expert panel convened by the National Academies concluded in April that for the vast majority of side effects, there was not enough data to accept or reject a link.

Asked at a recent congressional hearing whether the nation’s vaccine-safety surveillance was sufficient, Dr. Peter Marks, director of the F.D.A.’s Center for Biologics Evaluation and Research, said, “I do believe we could do better.”

In some countries with centralized health care systems, officials have actively sought out reports of serious side effects of Covid vaccines and reached conclusions that U.S. health authorities have not.

In Hong Kong, the government analyzed centralized medical records of patients after vaccination and paid people to come forward with problems. The strategy identified “a lot of mild cases that other countries would not otherwise pick up,” said Ian Wong, a researcher at the University of Hong Kong who led the nation’s vaccine safety efforts.

That included the finding that in rare instances — about seven per million doses — the Pfizer-BioNTech vaccine triggered a bout of shingles serious enough to require hospitalization.

The European Medicines Agency has linked the Pfizer and Moderna vaccines to facial paralysis, tingling sensations and numbness. The E.M.A. also counts tinnitus as a side effect of the Johnson & Johnson vaccine, although the American health agencies do not. There are more than 17,000 reports of tinnitus following Covid vaccination in VAERS.

Are the two linked? It’s not clear. As many as one in four adults has some form of tinnitus. Stress, anxiety, grief and aging can lead to the condition, as can infections like Covid itself and the flu.

There is no test or scan for tinnitus, and scientists cannot easily study it because the inner ear is tiny, delicate and encased in bone, said Dr. Konstantina Stankovic, an otolaryngologist at Stanford University.

Still, an analysis of health records from nearly 2.6 million people in the United States found that about 0.04 percent , or about 1,000, were diagnosed with tinnitus within three weeks of their first mRNA shot. In March, researchers in Australia published a study linking tinnitus and vertigo to the vaccines .

The F.D.A. is monitoring reports of tinnitus, but “at this time, the available evidence does not suggest a causal association with the Covid-19 vaccines,” the agency said in a statement.

Despite surveillance efforts, U.S. officials were not the first to identify a significant Covid vaccine side effect: myocarditis in young people receiving mRNA vaccines. It was Israeli authorities who first raised the alarm in April 2021. Officials in the United States said at the time that they had not seen a link.

On May 22, 2021, news broke that the C.D.C. was investigating a “relatively few” cases of myocarditis. By June 23, the number of myocarditis reports in VAERS had risen to more than 1,200 — a hint that it is important to tell doctors and patients what to look for.

Later analyses showed that the risk for myocarditis and pericarditis, a related condition, is highest after a second dose of an mRNA Covid vaccine in adolescent males aged 12 to 17 years.

In many people, vaccine-related myocarditis is transient. But some patients continue to experience pain, breathlessness and depression, and some show persistent changes on heart scans . The C.D.C. has said there were no confirmed deaths related to myocarditis, but in fact there have been several accounts of deaths reported post-vaccination .

Pervasive Misinformation

The rise of the anti-vaccine movement has made it difficult for scientists, in and out of government, to candidly address potential side effects, some experts said. Much of the narrative on the purported dangers of Covid vaccines is patently false, or at least exaggerated, cooked up by savvy anti-vaccine campaigns.

Questions about Covid vaccine safety are core to Robert F. Kennedy Jr.’s presidential campaign. Citing debunked theories about altered DNA, Florida’s surgeon general has called for a halt to Covid vaccination in the state.

“The sheer nature of misinformation, the scale of misinformation, is staggering, and anything will be twisted to make it seem like it’s not just a devastating side effect but proof of a massive cover-up,” said Dr. Joshua Sharfstein, a vice dean at Johns Hopkins University.

Among the hundreds of millions of Americans who were immunized for Covid, some number would have had heart attacks or strokes anyway. Some women would have miscarried. How to distinguish those caused by the vaccine from those that are coincidences? The only way to resolve the question is intense research .

But the National Institutes of Health is conducting virtually no studies on Covid vaccine safety, several experts noted. William Murphy, a cancer researcher who worked at the N.I.H. for 12 years, has been prodding federal health officials to initiate these studies since 2021.

The officials each responded with “that very tired mantra: ‘But the virus is worse,’” Dr. Murphy recalled. “Yes, the virus is worse, but that doesn’t obviate doing research to make sure that there may be other options.”

A deeper understanding of possible side effects, and who is at risk for them, could have implications for the design of future vaccines, or may indicate that for some young and healthy people, the benefit of Covid shots may no longer outweigh the risks — as some European countries have determined.

Thorough research might also speed assistance to thousands of Americans who say they were injured.

The federal government has long run the National Vaccine Injury Compensation Program , designed to compensate people who suffer injuries after vaccination. Established more than three decades ago, the program sets no limit on the amounts awarded to people found to have been harmed.

But Covid vaccines are not covered by that fund because Congress has not made them subject to the excise tax that pays for it. Some lawmakers have introduced bills to make the change.

Instead, claims regarding Covid vaccines go to the Countermeasures Injury Compensation Program . Intended for public health emergencies, this program has narrow criteria to pay out and sets a limit of $50,000, with stringent standards of proof.

It requires applicants to prove within a year of the injury that it was “the direct result” of getting the Covid vaccine, based on “compelling, reliable, valid, medical, and scientific evidence.”

The program had only four staff members at the beginning of the pandemic, and now has 35 people evaluating claims. Still, it has reviewed only a fraction of the 13,000 claims filed, and has paid out only a dozen.

Dr. Ilka Warshawsky, a 58-year-old pathologist, said she lost all hearing in her right ear after a Covid booster shot. But hearing loss is not a recognized side effect of Covid vaccination.

The compensation program for Covid vaccines sets a high bar for proof, she said, yet offers little information on how to meet it: “These adverse events can be debilitating and life-altering, and so it’s very upsetting that they’re not acknowledged or addressed.”

Dr. Zimmerman, the neuroscientist, submitted her application in October 2021 and provided dozens of supporting medical documents. She received a claim number only in January 2023.

In adjudicating her claim for workers’ compensation, Washington State officials accepted that Covid vaccination caused her injury, but she has yet to get a decision from the federal program.

One of her therapists recently told her she might never be able to live independently again.

“That felt like a devastating blow,” Dr. Zimmerman said. “But I’m trying not to lose hope there will someday be a treatment and a way to cover it.”

Apoorva Mandavilli is a reporter focused on science and global health. She was a part of the team that won the 2021 Pulitzer Prize for Public Service for coverage of the pandemic. More about Apoorva Mandavilli

Advertisement