critical appraisal research essay

How To Write a Critical Appraisal

A critical appraisal is an academic approach that refers to the systematic identification of strengths and weakness of a research article with the intent of evaluating the usefulness and validity of the work’s research findings. As with all essays, you need to be clear, concise, and logical in your presentation of arguments, analysis, and evaluation. However, in a critical appraisal there are some specific sections which need to be considered which will form the main basis of your work.

Structure of a Critical Appraisal

Introduction.

Your introduction should introduce the work to be appraised, and how you intend to proceed. In other words, you set out how you will be assessing the article and the criteria you will use. Focusing your introduction on these areas will ensure that your readers understand your purpose and are interested to read on. It needs to be clear that you are undertaking a scientific and literary dissection and examination of the indicated work to assess its validity and credibility, expressed in an interesting and motivational way.

Body of the Work

The body of the work should be separated into clear paragraphs that cover each section of the work and sub-sections for each point that is being covered. In all paragraphs your perspectives should be backed up with hard evidence from credible sources (fully cited and referenced at the end), and not be expressed as an opinion or your own personal point of view. Remember this is a critical appraisal and not a presentation of negative parts of the work.

When appraising the introduction of the article, you should ask yourself whether the article answers the main question it poses. Alongside this look at the date of publication, generally you want works to be within the past 5 years, unless they are seminal works which have strongly influenced subsequent developments in the field. Identify whether the journal in which the article was published is peer reviewed and importantly whether a hypothesis has been presented. Be objective, concise, and coherent in your presentation of this information.

Once you have appraised the introduction you can move onto the methods (or the body of the text if the work is not of a scientific or experimental nature). To effectively appraise the methods, you need to examine whether the approaches used to draw conclusions (i.e., the methodology) is appropriate for the research question, or overall topic. If not, indicate why not, in your appraisal, with evidence to back up your reasoning. Examine the sample population (if there is one), or the data gathered and evaluate whether it is appropriate, sufficient, and viable, before considering the data collection methods and survey instruments used. Are they fit for purpose? Do they meet the needs of the paper? Again, your arguments should be backed up by strong, viable sources that have credible foundations and origins.

One of the most significant areas of appraisal is the results and conclusions presented by the authors of the work. In the case of the results, you need to identify whether there are facts and figures presented to confirm findings, assess whether any statistical tests used are viable, reliable, and appropriate to the work conducted. In addition, whether they have been clearly explained and introduced during the work. In regard to the results presented by the authors you need to present evidence that they have been unbiased and objective, and if not, present evidence of how they have been biased. In this section you should also dissect the results and identify whether any statistical significance reported is accurate and whether the results presented and discussed align with any tables or figures presented.

The final element of the body text is the appraisal of the discussion and conclusion sections. In this case there is a need to identify whether the authors have drawn realistic conclusions from their available data, whether they have identified any clear limitations to their work and whether the conclusions they have drawn are the same as those you would have done had you been presented with the findings.

The conclusion of the appraisal should not introduce any new information but should be a concise summing up of the key points identified in the body text. The conclusion should be a condensation (or precis) of all that you have already written. The aim is bringing together the whole paper and state an opinion (based on evaluated evidence) of how valid and reliable the paper being appraised can be considered to be in the subject area. In all cases, you should reference and cite all sources used. To help you achieve a first class critical appraisal we have put together some key phrases that can help lift you work above that of others.

Key Phrases for a Critical Appraisal

• Whilst the title might suggest
• The focus of the work appears to be…
• The author challenges the notion that…
• The author makes the claim that…
• The article makes a strong contribution through…
• The approach provides the opportunity to…
• The authors consider…
• The argument is not entirely convincing because…
• However, whilst it can be agreed that… it should also be noted that…
• Several crucial questions are left unanswered…
• It would have been more appropriate to have stated that…
• This framework extends and increases…
• The authors correctly conclude that…
• The authors efforts can be considered as…
• Less convincing is the generalisation that…
• This appears to mislead readers indicating that…
• This research proves to be timely and particularly significant in the light of…

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• v.12(2); Apr-Jun 2021

Critical appraisal of published research papers – A reinforcing tool for research methodology: Questionnaire-based study

Snehalata gajbhiye.

Department of Pharmacology and Therapeutics, Seth GS Medical College and KEM Hospital, Mumbai, Maharashtra, India

Raakhi Tripathi

Urwashi parmar, nishtha khatri, anirudha potey.

1 Department of Clinical Trials, Serum Institute of India, Pune, Maharashtra, India

Background and Objectives:

Critical appraisal of published research papers is routinely conducted as a journal club (JC) activity in pharmacology departments of various medical colleges across Maharashtra, and it forms an important part of their postgraduate curriculum. The objective of this study was to evaluate the perception of pharmacology postgraduate students and teachers toward use of critical appraisal as a reinforcing tool for research methodology. Evaluation of performance of the in-house pharmacology postgraduate students in the critical appraisal activity constituted secondary objective of the study.

Materials and Methods:

The study was conducted in two parts. In Part I, a cross-sectional questionnaire-based evaluation on perception toward critical appraisal activity was carried out among pharmacology postgraduate students and teachers. In Part II of the study, JC score sheets of 2 nd - and 3 rd -year pharmacology students over the past 4 years were evaluated.

One hundred and twenty-seven postgraduate students and 32 teachers participated in Part I of the study. About 118 (92.9%) students and 28 (87.5%) faculties considered the critical appraisal activity to be beneficial for the students. JC score sheet assessments suggested that there was a statistically significant improvement in overall scores obtained by postgraduate students ( n = 25) in their last JC as compared to the first JC.

Conclusion:

Journal article criticism is a crucial tool to develop a research attitude among postgraduate students. Participation in the JC activity led to the improvement in the skill of critical appraisal of published research articles, but this improvement was not educationally relevant.

INTRODUCTION

Critical appraisal of a research paper is defined as “The process of carefully and systematically examining research to judge its trustworthiness, value and relevance in a particular context.”[ 1 ] Since scientific literature is rapidly expanding with more than 12,000 articles being added to the MEDLINE database per week,[ 2 ] critical appraisal is very important to distinguish scientifically useful and well-written articles from imprecise articles.

Educational authorities like the Medical Council of India (MCI) and Maharashtra University of Health Sciences (MUHS) have stated in pharmacology postgraduate curriculum that students must critically appraise research papers. To impart training toward these skills, MCI and MUHS have emphasized on the introduction of journal club (JC) activity for postgraduate (PG) students, wherein students review a published original research paper and state the merits and demerits of the paper. Abiding by this, pharmacology departments across various medical colleges in Maharashtra organize JC at frequent intervals[ 3 , 4 ] and students discuss varied aspects of the article with teaching faculty of the department.[ 5 ] Moreover, this activity carries a significant weightage of marks in the pharmacology university examination. As postgraduate students attend this activity throughout their 3-year tenure, it was perceived by the authors that this activity of critical appraisal of research papers could emerge as a tool for reinforcing the knowledge of research methodology. Hence, a questionnaire-based study was designed to find out the perceptions from PG students and teachers.

There have been studies that have laid emphasis on the procedure of conducting critical appraisal of research papers and its application into clinical practice.[ 6 , 7 ] However, there are no studies that have evaluated how well students are able to critically appraise a research paper. The Department of Pharmacology and Therapeutics at Seth GS Medical College has developed an evaluation method to score the PG students on this skill and this tool has been implemented for the last 5 years. Since there are no research data available on the performance of PG Pharmacology students in JC, capturing the critical appraisal activity evaluation scores of in-house PG students was chosen as another objective of the study.

MATERIALS AND METHODS

Description of the journal club activity.

JC is conducted in the Department of Pharmacology and Therapeutics at Seth GS Medical College once in every 2 weeks. During the JC activity, postgraduate students critically appraise published original research articles on their completeness and aptness in terms of the following: study title, rationale, objectives, study design, methodology-study population, inclusion/exclusion criteria, duration, intervention and safety/efficacy variables, randomization, blinding, statistical analysis, results, discussion, conclusion, references, and abstract. All postgraduate students attend this activity, while one of them critically appraises the article (who has received the research paper given by one of the faculty members 5 days before the day of JC). Other faculties also attend these sessions and facilitate the discussions. As the student comments on various sections of the paper, the same predecided faculty who gave the article (single assessor) evaluates the student on a total score of 100 which is split per section as follows: Introduction –20 marks, Methodology –20 marks, Discussion – 20 marks, Results and Conclusion –20 marks, References –10 marks, and Title, Abstract, and Keywords – 10 marks. However, there are no standard operating procedures to assess the performance of students at JC.

Methodology

After seeking permission from the Institutional Ethics Committee, the study was conducted in two parts. Part I consisted of a cross-sectional questionnaire-based survey that was conducted from October 2016 to September 2017. A questionnaire to evaluate perception towards the activity of critical appraisal of published papers as research methodology reinforcing tool was developed by the study investigators. The questionnaire consisted of 20 questions: 14 questions [refer Figure 1 ] graded on a 3-point Likert scale (agree, neutral, and disagree), 1 multiple choice selection question, 2 dichotomous questions, 1 semi-open-ended questions, and 2 open-ended questions. Content validation for this questionnaire was carried out with the help of eight pharmacology teachers. The content validity ratio per item was calculated and each item in the questionnaire had a CVR ratio (CVR) of >0.75.[ 8 ] The perception questionnaire was either E-mailed or sent through WhatsApp to PG pharmacology students and teaching faculty in pharmacology departments at various medical colleges across Maharashtra. Informed consent was obtained on E-mail from all the participants.

Graphical representation of the percentage of students/teachers who agreed that critical appraisal of research helped them improve their knowledge on various aspects of research, perceived that faculty participation is important in this activity, and considered critical appraisal activity beneficial for students. The numbers adjacent to the bar diagrams indicate the raw number of students/faculty who agreed, while brackets indicate %

Part II of the study consisted of evaluating the performance of postgraduate students toward skills of critical appraisal of published papers. For this purpose, marks obtained by 2 nd - and 3 rd -year residents during JC sessions conducted over a period of 4 years from October 2013 to September 2017 were recorded and analyzed. No data on personal identifiers of the students were captured.

Statistical analysis

Marks obtained by postgraduate students in their first and last JC were compared using Wilcoxon signed-rank test, while marks obtained by 2 nd - and 3 rd -year postgraduate students were compared using Mann–Whitney test since the data were nonparametric. These statistical analyses were performed using GraphPad Prism statistical software, San Diego, Calfornia, USA, Version 7.0d. Data obtained from the perception questionnaire were entered in Microsoft Excel sheet and were expressed as frequencies (percentages) using descriptive statistics.

Participants who answered all items of the questionnaire were considered as complete responders and only completed questionnaires were analyzed. The questionnaire was sent through an E-mail to 100 students and through WhatsApp to 68 students. Out of the 100 students who received the questionnaire through E-mail, 79 responded completely and 8 were incomplete responders, while 13 students did not revert back. Out of the 68 students who received the questionnaire through WhatsApp, 48 responded completely, 6 gave an incomplete response, and 14 students did not revert back. Hence, of the 168 postgraduate students who received the questionnaire, 127 responded completely (student response rate for analysis = 75.6%). The questionnaire was E-mailed to 33 faculties and was sent through WhatsApp to 25 faculties. Out of the 33 faculties who received the questionnaire through E-mail, 19 responded completely, 5 responded incompletely, and 9 did not respond at all. Out of the 25 faculties who received the questionnaire through WhatsApp, 13 responded completely, 3 were incomplete responders, and 9 did not respond at all. Hence, of a total of 58 faculties who were contacted, 32 responded completely (faculty response rate for analysis = 55%). For Part I of the study, responses on the perception questionnaire from 127 postgraduate students and 32 postgraduate teachers were recorded and analyzed. None of the faculty who participated in the validation of the questionnaire participated in the survey. Number of responses obtained region wise (Mumbai region and rest of Maharashtra region) have been depicted in Table 1 .

Region-wise distribution of responses

Number of responses obtained from students/faculty belonging to Mumbai colleges and rest of Maharashtra colleges. Brackets indicate percentages

As per the data obtained on the Likert scale questions, 102 (80.3%) students and 29 (90.6%) teachers agreed that critical appraisal trains the students in doing a review of literature before selecting a particular research topic. Majority of the participants, i.e., 104 (81.9%) students and 29 (90.6%) teachers also believed that the activity increases student's knowledge regarding various experimental evaluation techniques. Moreover, 112 (88.2%) students and 27 (84.4%) faculty considered that critical appraisal activity results in improved skills of writing and understanding methodology section of research articles in terms of inclusion/exclusion criteria, endpoints, and safety/efficacy variables. About 103 (81.1%) students and 24 (75%) teachers perceived that this activity results in refinement of the student's research work. About 118 (92.9%) students and 28 (87.5%) faculty considered the critical appraisal activity to be beneficial for the students. Responses to 14 individual Likert scale items of the questionnaire have been depicted in Figure 1 .

With respect to the multiple choice selection question, 66 (52%) students and 16 (50%) teachers opined that faculty should select the paper, 53 (41.7%) students and 9 (28.1%) teachers stated that the papers should be selected by the presenting student himself/herself, while 8 (6.3%) students and 7 (21.9%) teachers expressed that some other student should select the paper to be presented at the JC.

The responses to dichotomous questions were as follows: majority of the students, that is, 109 (85.8%) and 23 (71.9%) teachers perceived that a standard checklist for article review should be given to the students before critical appraisal of journal article. Open-ended questions of the questionnaire invited suggestions from the participants regarding ways of getting trained on critical appraisal skills and of improving JC activity. Some of the suggestions given by faculty were as follows: increasing the frequency of JC activity, discussion of cited articles and new guidelines related to it, selecting all types of articles for criticism rather than only randomized controlled trials, and regular yearly exams on article criticism. Students stated that regular and frequent article criticism activity, practice of writing letter to the editor after criticism, active participation by peers and faculty, increasing weightage of marks for critical appraisal of papers in university examinations (at present marks are 50 out of 400), and a formal training for research criticism from 1 st year of postgraduation could improve critical appraisal program.

In Part II of this study, performance of the students on the skill of critical appraisal of papers was evaluated. Complete data of the first and last JC scores of a total of 25 students of the department were available, and when these scores were compared, it was seen that there was a statistically significant improvement in the overall scores ( P = 0.04), as well as in the scores obtained in methodology ( P = 0.03) and results section ( P = 0.02). This is depicted in Table 2 . Although statistically significant, the differences in scores in the methodology section, results section, and overall scores were 1.28/20, 1.28/20, and 4.36/100, respectively, amounting to 5.4%, 5.4%, and 4.36% higher scores in the last JC, which may not be considered educationally relevant (practically significant). The quantum of difference that would be considered practically significant was not decided a priori .

Comparison of marks obtained by pharmacology residents in their first and last journal club

Marks have been represented as mean±SD. The maximum marks that can be obtained in each section have been stated as maximum. *Indicates statistically significant ( P <0.05). IQR=Interquartile range, SD=Standard deviation

Scores of two groups, one group consisting of 2 nd -year postgraduate students ( n = 44) and second group consisting of 3 rd -year postgraduate students ( n = 32) were compared and revealed no statistically significant difference in overall score ( P = 0.84). This is depicted in Table 3 . Since the quantum of difference in the overall scores was meager 0.84/100 (0.84%), it cannot be considered practically significant.

Comparison of marks obtained by 2 nd - and 3 rd -year pharmacology residents in the activity of critical appraisal of research articles

Marks have been represented as mean±SD. The maximum marks that can be obtained in each section have been stated as maximum. P <0.05 was considered to be statistically significant. IQR=Interquartile range, SD=Standard deviation

The present study gauged the perception of the pharmacology postgraduate students and teachers toward the use of critical appraisal activity as a reinforcing tool for research methodology. Both students and faculties (>50%) believed that critical appraisal activity increases student's knowledge on principles of ethics, experimental evaluation techniques, CONSORT guidelines, statistical analysis, concept of conflict of interest, current trends and recent advances in Pharmacology and trains on doing a review of literature, and improves skills on protocol writing and referencing. In the study conducted by Crank-Patton et al ., a survey on 278 general surgery program directors was carried out and more than 50% indicated that JC was important to their training program.[ 9 ]

The grading template used in Part II of the study was based on the IMRaD structure. Hence, equal weightage was given to the Introduction, Methodology, Results, and Discussion sections and lesser weightage was given to the references and title, abstract, and keywords sections.[ 10 ] While evaluating the scores obtained by 25 students in their first and last JC, it was seen that there was a statistically significant improvement in the overall scores of the students in their last JC. However, the meager improvement in scores cannot be considered educationally relevant, as the authors expected the students to score >90% for the upgrade to be considered educationally impactful. The above findings suggest that even though participation in the JC activity led to a steady increase in student's performance (~4%), the increment was not as expected. In addition, the students did not portray an excellent performance (>90%), with average scores being around 72% even in the last JC. This can be probably explained by the fact that students perform this activity in a routine setting and not in an examination setting. Unlike the scenario in an examination, students were aware that even if they performed at a mediocre level, there would be no repercussions.

A separate comparison of scores obtained by 44 students in their 2 nd year and 32 students in their 3 rd year of postgraduation students was also done. The number of student evaluation sheets reviewed for this analysis was greater than the number of student evaluation sheets reviewed to compare first and last JC scores. This can be spelled out by the fact that many students were still in 2 nd year when this analysis was done and the score data for their last JC, which would take place in 3 rd year, was not available. In addition, few students were asked to present at JC multiple times during the 2 nd /3 rd year of their postgraduation.

While evaluating the critical appraisal scores obtained by 2 nd - and 3 rd -year postgraduate students, it was found that although the 3 rd -year students had a mean overall score greater than the 2 nd -year students, this difference was not statistically significant. During the 1 st year of MD Pharmacology course, students at the study center attend JC once in every 2 weeks. Even though the 1 st -year students do not themselves present in JC, they listen and observe the criticism points stated by senior peers presenting at the JC, and thereby, incur substantial amount of knowledge required to critically appraise papers. By the time, they become 2 nd -year students, they are already well versed with the program and this could have led to similar overall mean scores between the 2 nd -year students (71.50 ± 10.71) and 3 rd -year students (72.34 ± 10.85). This finding suggests that attentive listening is as important as active participation in the JC. Moreover, although students are well acquainted with the process of criticism when they are in their 3 rd year, there is certainly a scope for improvement in terms of the mean overall scores.

Similar results were obtained in a study conducted by Stern et al ., in which 62 students in the internal medicine program at the New England Medical Center were asked to respond to a questionnaire, evaluate a sample article, and complete a self-assessment of competence in evaluation of research. Twenty-eight residents returned the questionnaire and the composite score for the resident's objective assessment was not significantly correlated with the postgraduate year or self-assessed critical appraisal skill.[ 11 ]

Article criticism activity provides the students with practical experience of techniques taught in research methodology workshop. However, this should be supplemented with activities that assess the improvement of designing and presenting studies, such as protocol and paper writing. Thus, critical appraisal plays a significant role in reinforcing good research practices among the new generation of physicians. Moreover, critical appraisal is an integral part of PG assessment, and although the current format of conducting JCs did not portray a clinically meaningful improvement, the authors believe that it is important to continue this activity with certain modifications suggested by students who participated in this study. Students suggested that an increase in the frequency of critical appraisal activity accompanied by the display of active participation by peers and faculty could help in the betterment of this activity. This should be brought to attention of the faculty, as students seem to be interested to learn. Critical appraisal should be a two-way teaching–learning process between the students and faculty and not a dire need for satisfying the students' eligibility criteria for postgraduate university examinations. This activity is not only for the trainee doctors but also a part of the overall faculty development program.[ 12 ]

In the present era, JCs have been used as a tool to not only teach critical appraisal skills but also to teach other necessary aspects such as research design, medical statistics, clinical epidemiology, and clinical decision-making.[ 13 , 14 ] A study conducted by Khan in 2013 suggested that success of JC program can be ensured if institutes develop a defined JC objective for the development of learning capability of students and also if they cultivate more skilled faculties.[ 15 ] A good JC is believed to facilitate relevant, meaningful scientific discussion, and evaluation of the research updates that will eventually benefit the patient care.[ 12 ]

Although there is a lot of literature emphasizing the importance of JC, there is a lack of studies that have evaluated the outcome of such activity. One such study conducted by Ibrahim et al . assessed the importance of critical appraisal as an activity in surgical trainees in Nigeria. They reported that 92.42% trainees considered the activity to be important or very important and 48% trainees stated that the activity helped in improving literature search.[ 16 ]

This study is unique since it is the first of its kind to evaluate how well students are able to critically appraise a research paper. Moreover, the study has taken into consideration the due opinions of the students as well as faculties, unlike the previous literature which has laid emphasis on only student's perception. A limitation of this study is that sample size for faculties was smaller than the students, as it was not possible to convince the distant faculty in other cities to fill the survey. Besides, there may be a variation in the manner of conduct of the critical appraisal activity in pharmacology departments across the various medical colleges in the country. Another limitation of this study was that a single assessor graded a single student during one particular JC. Nevertheless, each student presented at multiple JC and thereby came across multiple assessors. Since the articles addressed at different JC were disparate, interobserver variability was not taken into account in this study. Furthermore, the authors did not make an a priori decision on the quantum of increase in scores that would be considered educationally meaningful.

Pharmacology students and teachers acknowledge the role of critical appraisal in improving the ability to understand the crucial concepts of research methodology and research conduct. In our institute, participation in the JC activity led to an improvement in the skill of critical appraisal of published research articles among the pharmacology postgraduate students. However, this improvement was not educationally relevant. The scores obtained by final-year postgraduate students in this activity were nearly 72% indicating that there is still scope of betterment in this skill.

Financial support and sponsorship

Conflicts of interest.

There are no conflicts of interest.

Acknowledgments

We would like to acknowledge the support rendered by the entire Department of Pharmacology and Therapeutics at Seth GS Medical College.

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Critical appraisal of a clinical research paper

What one needs to know.

Manjali, Jifmi Jose; Gupta, Tejpal

Department of Radiation Oncology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, Maharashtra, India

Address for correspondence: Dr. Tejpal Gupta, ACTREC, Tata Memorial Centre, Homi Bhabha National Institute, Kharghar, Navi Mumbai - 410 210, Maharashtra, India. E-mail: [email protected]

Received May 25, 2020

Received in revised form June 11, 2020

Accepted June 19, 2020

This is an open access journal, and articles are distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as appropriate credit is given and the new creations are licensed under the identical terms.

In the present era of evidence-based medicine (EBM), integrating best research evidence into the clinical practice necessitates developing skills to critically evaluate and analyze the scientific literature. Critical appraisal is the process of systematically examining research evidence to assess its validity, results, and relevance to inform clinical decision-making. All components of a clinical research article need to be appraised as per the study design and conduct. As research bias can be introduced at every step in the flow of a study leading to erroneous conclusions, it is essential that suitable measures are adopted to mitigate bias. Several tools have been developed for the critical appraisal of scientific literature, including grading of evidence to help clinicians in the pursuit of EBM in a systematic manner. In this review, we discuss the broad framework for the critical appraisal of a clinical research paper, along with some of the relevant guidelines and recommendations.

INTRODUCTION

Medical research information is ever growing and branching day by day. Despite the vastness of medical literature, it is necessary that as clinicians we offer the best treatment to our patients as per the current knowledge. Integrating best research evidence with clinical expertise and patient values has led to the concept of evidence-based medicine (EBM).[ 1 ] Although this philosophy originated in the middle of the 19 th century,[ 2 ] it first appeared in its current form in the modern medical literature in 1991.[ 3 ] EBM is defined as the conscientious, explicit, and judicious use of the current best evidence in making decisions about the care of an individual patient.[ 1 ] The essentials of EBM include generating a clinical question, tracking the best available evidence, critically evaluating the evidence for validity and clinical usefulness, further applying the results to clinical practice, and evaluating its performance. Appropriate application of EBM can result in cost-effectiveness and improve health-care efficiency.[ 4 ] Without continual accumulation of new knowledge, existing dogmas and paradigms quickly become outdated and may prove detrimental to the patients. The current growth of medical literature with 1.8 million scientific articles published in the year 2012,[ 5 ] often makes it difficult for the clinicians to keep pace with the vast amount of scientific data, thus making foraging (alerts to new information) and hunting (finding answers to clinical questions) essential skills to help navigate the so-called “jungle” of information.[ 6 ] Therefore, it is essential that health-care professionals read medical literature selectively to effectively utilize their limited time and assiduously imbibe new knowledge to improve decision-making for their patients. To practice EBM in its true sense, a clinician not only needs to devote time to develop the skill of effectively searching the literature, but also needs to learn to evaluate the significance, methodology, outcomes, and transparency of the study.[ 4 ] Along with the evaluation and interpretation of a study, a thorough understanding of its methodology is necessary. It is common knowledge that studies with positive results are relatively easy to publish.[ 7 8 ] However, it is the critical appraisal of any research study (even those with negative results) that helps us to understand the science better and ask relevant questions in future using an appropriate study design and endpoints. Therefore, this review is focused on the framework for the critical appraisal of a clinical research paper. In addition, we have also discussed some of the relevant guidelines and recommendations for the critical appraisal of clinical research papers.

CRITICAL APPRAISAL

Critical appraisal is the process of systematically examining the research evidence to assess its validity, results, and relevance before using it to inform a decision.[ 9 ] It entails the following:

• Balanced assessment of the benefits/strengths and flaws/weaknesses of a study
• Assessment of the research process and results
• Consideration of quantitative and qualitative aspects.

Critical appraisal is performed to assess the following

aspects of a study:

• Validity – Is the methodology robust?
• Reliability – Are the results credible?
• Applicability– Do the results have the potential to change the current practice?

Contrary to the common belief, a critical appraisal is not the negative dismissal of any piece of research or an assessment of the results alone; it is neither solely based on a statistical analysis nor a process undertaken by the experts only. When performing a critical appraisal of a scientific article, it is essential that we know its basic composition and assess every section meticulously.

Initial assessment

This involves taking a generalized look at the details of the article. The journal it was published in holds special value – a peer reviewed, indexed journal with a good impact factor adds robustness to the paper. The setting, timeline, and year of publication of the study also need to be noted, as they provide a better understanding of the evolution of thoughts in that particular subject. Declaration of the conflicts of interest by the authors, the role of the funding source if any, and any potential commercial bias should also be noted.[ 10 ]

COMPONENTS OF A CLINICAL RESEARCH PAPER

The components of any scientific article or clinical research paper remain largely the same. An article begins with a title, abstract, and keywords, which are followed by the main text, which includes the IMRAD – introduction, methods, results and discussion, and ends with the conclusion and references.

It is a brief summary of the research article which helps the readers understand the purpose, methods, and results of the study. Although an abstract may provide a brief overview of the study, the full text of the article needs to be read and evaluated for a thorough understanding. There are two types of abstracts, namely structured and unstructured. A structured abstract comprises different sections typically labelled as background/purpose, methods, results, and conclusion, whereas an unstructured abstract is not divided into these sections.

Introduction

The introduction of a research paper familiarizes the reader with the topic. It refers to the current evidence in the particular subject and the possible lacunae which necessitate the present study. In other words, the introduction puts the study in perspective. The findings of other related studies have to be quoted and referenced, especially their central statements. The introduction also needs to justify the appropriateness of the chosen study.[ 11 ]

This section highlights the procedure followed while conducting the study. It provides all the data necessary for the study's appraisal and lays out the study design which is paramount. For clinical research articles, this section should describe the participant or patient/population/problem (P), intervention (I), comparison (C), outcome (O), and study design (S) PICO(S), generally referred to as the PICO(S) framework [ Table 1 ].

Study designs and levels of evidence

Study designs are broadly divided into descriptive and interventional studies,[ 12 ] which can be further subdivided as shown in Figure 1 . Each study design has its own characteristics and should be used in the appropriate setting. The various study designs form the building blocks of evidence. This in turn justifies the need for a hierarchical classification of evidence, referred to as “Levels of Evidence,” as it forms the cornerstone of EBM [ Table 2 ]. Most medical journals now mandate that the submitted manuscript conform to and comply with the clinical research reporting statements and guidelines as applicable to the study design [ Table 3 ] to maintain clarity, transparency, and reproducibility and ensure comparability across different studies asking the same research question. As per the study design, the appropriate descriptive and inferential statistical analyses should be specified in the statistical plan. For prospective studies, a clear mention of sample size calculation (depending on the type of study, power, alpha error, meaningful difference, and variance) is mandatory, so as to identify whether the study was adequately powered.[ 13 ] The endpoints (primary, secondary, and exploratory, if any) should be mentioned clearly along with the exact methods used for the measurement of the variables.

Statistical testing

The statistical framework of any research study is commonly based on testing the null hypothesis, wherein the results are deemed significant by comparing P values obtained from an experimental dataset to a predefined significance level (0.05 being the most popular choice). By definition, P value is the probability under the specified statistical model to obtain a statistical summary equal to or more extreme than the one computed from the data and can range from 0 to 1. P < 0.05 indicates that results are unlikely to be due to chance alone. Unfortunately, P value does not indicate the magnitude of the observed difference, which may also be desirable. An alternative and complementary approach is the use of confidence intervals (CI), which is a range of values calculated from the observed data, that is likely to contain the true value at a specified probability. The probability is chosen by the investigator, and it is set customarily at 95% (1– alpha error of 0.05). CI provides information that may be used to test hypotheses; additionally, they provide information related to the precision, power, sample size, and effect size.

This section contains the findings of the study, presented clearly and objectively. The results obtained using the descriptive and inferential statistical analyses (as mentioned in the methods section) should be described. The use of tables and figures, including graphical representation [ Table 4 ], is encouraged to improve the clarity;[ 14 ] however, the duplication of these data in the text should be avoided.

The discussion section presents the authors' interpretations of the obtained results. This section includes:

• A comparison of the study results with what is currently known, drawing similarities and differences
• Novel findings of the study that have added to the existing body of knowledge
• Caveats and limitations.

It is imperative that the key relevant references are cited in any research paper in the appropriate format which allows the readers to access the original source of the specified statement or evidence. A brief look at the reference list gives an overview of how well the indexed medical literature was searched for the purpose of writing the manuscript.

Overall assessment

After a careful assessment of the various sections of a research article, it is necessary to assess the relevance of the study findings to the present scenario and weigh the potential benefits and drawbacks of its application to the population. In this context, it is necessary that the integrity of the intervention be noted. This can be verified by assessing the factors such as adherence to the specified program, the exposure needed, quality of delivery, participant responsiveness, and potential contamination. This relates to the feasibility of applying the intervention to the community.

BIAS IN CLINICAL RESEARCH

Research articles are the media through which science is communicated, and it is necessary that we adhere to the basic principles of transparency and accuracy when communicating our findings. Any such trend or deviation from the truth in data collection, analysis, interpretation, or publication is called bias.[ 15 ] This may lead to erroneous conclusions, and hence, all scientists and clinicians must be aware of the bias and employ all possible measures to mitigate it.

The extent to which a study is free from bias defines its internal validity. Internal validity is different from the external validity and precision. The external validity of a study is about its generalizability or applicability (depends on the purpose of the study), while precision is the extent to which a study is free from random errors (depends on the number of participants). A study is irrelevant without internal validity even if it is applicable and precise.[ 16 ] A bias can be introduced at every step in the flow of a study [ Figure 2 ].

The various types of biases in clinical research include:

• Selection bias: This happens while recruiting patients. This may lead to the differences in the way patients are accepted or rejected for a trial and the way in which interventions are assigned to the individuals. We need to assess whether the study population is a true representative of the target population. Furthermore, when there is no or an inadequate sequence generation, it can result in the over-estimation of treatment effects compared to randomized trials.[ 14 ] This can be mitigated by using a process called randomization. Randomization is the process of assigning clinical trial participants to treatment groups, such that each participant has an equal chance of being assigned to a particular group. This process should be completely random (e.g., tossing a coin, using a computer program, and throwing dice). When the process is not exactly random (e.g., randomization by date of birth, odd-even numbers, alternation, registration date, etc.), there is a significant potential for a selection bias
• Allocation bias: This is a bias that sets in when the person responsible for the study also allocates the treatment. It is known that inadequate or unclear concealment of allocation can lead to an overestimation of the treatment effects.[ 17 ] Adequate allocation concealment helps in mitigating this bias. This can be done by sequentially numbering identical drug containers or through central allocation by a person not involved in study enrollment
• Confounding bias: Having an effect on the dependent and independent variables through a spurious association, confounding factors can introduce a significant bias. Hence, the baseline characteristics need to be similar in the groups being compared. Known confounders can be managed during the selection process by stratified randomization (in randomized trials) and matching (in observational studies) or during analysis by meta-regression.[ 18 ] However, the unknown confounders can be minimized only through randomization
• Performance bias: This is a bias that is introduced because of the knowledge about the intervention allocation in the patient, investigator, or outcome assessor. This results in ascertainment or recall bias (patient), reporting bias (investigator), and detection bias (outcome assessor), all of which can lead to an overestimation of the treatment effects.[ 17 ] This can be mitigated by blinding – a process in which the treatment allocation is hidden from the patient, investigator, and/or outcome assessor. However, it has to be noted that blinding may not be practical or possible in all kinds of clinical trials
• Method bias: In clinical trials, it is necessary that the outcomes be assessed and recorded using valid and reliable tools, the lack of which can introduce a method bias[ 19 ]
• Attrition bias: This is a bias that is introduced because of the systematic differences between the groups in the loss of participants from the study. It is necessary to describe the completeness of the outcomes including the exclusions (along with the reasons), loss to follow-up, and drop-outs from the analysis
• Other bias: This includes any important concerns about biases not covered in the other domains.

Trial registration

In the recent times, it has become an ethical as well as a regulatory requirement in most countries to register the clinical trials prospectively before the enrollment of the first subject. Registration of a clinical trial is defined as the publication of an internationally agreed upon set of information about the design, conduct, and administration of any clinical trial on a publicly accessible website managed by a registry conforming to international standards. Apart from improving the awareness and visibility of the study, registration ensures transparency in the conduct and reduces publication bias and selective reporting. Some of the common sites are the ClinicalTrials. gov run by the National Library of Medicine of the National Institutes of Health (), Clinical Trials Registry-India () run by the Indian Council of Medical Research, and the International Clinical Trials Registry Platform () run by the World Health Organization.

Tools for critical appraisal

Several tools have been developed to assess the transparency of the scientific research papers and the degree of congruence of the research question with the study in the context of the various sections listed above [ Table 5 ].

Ethical considerations

Bad ethics cannot produce good science. Therefore, all scientific research must follow the ethical principles laid out in the declaration of Helsinki. For clinical research, it is mandatory that team members be trained in good clinical practice, familiarize themselves with clinical research methodology, and follow standard operating procedures as prescribed. Although the regulatory framework and landscape may vary to a certain extent depending upon the country where the research work is conducted, it is the responsibility of the Institutional Review Boards/Institutional Ethics Committees to provide study oversight such that the safety, well-being, and rights of the participants are adequately protected.

CONCLUSIONS

Critical appraisal is the systematic examination of the research evidence reported in the scientific articles to assess their validity, reliability, and applicability before using their findings to inform decision-making. It should be considered as the first step to grade the quality of evidence.

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How to critically appraise an article

• Jane M Young 1 &
• Michael J Solomon 2  

Nature Clinical Practice Gastroenterology & Hepatology volume  6 ,  pages 82–91 ( 2009 ) Cite this article

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Critical appraisal is a systematic process used to identify the strengths and weaknesses of a research article in order to assess the usefulness and validity of research findings. The most important components of a critical appraisal are an evaluation of the appropriateness of the study design for the research question and a careful assessment of the key methodological features of this design. Other factors that also should be considered include the suitability of the statistical methods used and their subsequent interpretation, potential conflicts of interest and the relevance of the research to one's own practice. This Review presents a 10-step guide to critical appraisal that aims to assist clinicians to identify the most relevant high-quality studies available to guide their clinical practice.

Critical appraisal is a systematic process used to identify the strengths and weaknesses of a research article

Critical appraisal provides a basis for decisions on whether to use the results of a study in clinical practice

Different study designs are prone to various sources of systematic bias

Design-specific, critical-appraisal checklists are useful tools to help assess study quality

Assessments of other factors, including the importance of the research question, the appropriateness of statistical analysis, the legitimacy of conclusions and potential conflicts of interest are an important part of the critical appraisal process

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Making sense of the literature: an introduction to critical appraisal for the primary care practitioner

How to appraise the literature: basic principles for the busy clinician - part 2: systematic reviews and meta-analyses

How to appraise the literature: basic principles for the busy clinician - part 1: randomised controlled trials

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Critical appraisal (CA) is an essential step in validating evidence based medicine (EBM), and the internet is a powerful tool to improve your understanding of CA.

The Public Health Resource Unit's website ( www.phru.nhs.uk/casp/appraisa.htm ) provides useful and easy checklists. You select the article that you wish to make the critical appraisal for, decide the type of study, and then download the relevant checklist. By answering the questions in the checklist, you will reach a conclusion about the usefulness of the article. In addition, there are non-virtual workshops that you may subscribe to, but these may lack the benefit of convenience offered by online learning.

The University of Birmingham offers a simple and useful presentation about critical appraisal ( www.bham.ac.uk/arif/casp/caspslides_files/frame.htm ), which provides a clear idea about CA. If CA is new to you this might be an ideal source and may also be used in departmental teaching.

In the Centre for Evidence-Based Medicine in Oxford ( www.cebm.net/cats.asp ) the Critically Appraised Topics Program, “CAT”, is a simple software program that helps clinicians to summarise the evidence. The program can be used to save any CA you have done on a previous occasion. When you access the site, if, for example, there is debate about some research that you have already appraised, you will be able to use the program as proof that you have done so.

The University of Sheffield's website ( www.shef.ac.uk/scharr/ir/units/critapp/index.htm ) gives further options in offering you guidance in how to appraise websites, how to present CA, and also links to other web resources including many from the BMJ .

The University of Alberta, Canada's website ( www.med.ualberta.ca/ebm ) gives free statistical analysis software for power and sample size, which is essential for the value of a study. EBM calculations are also available, plus checklists of a similar format to those found on the Public Health Resource Unit's website.

Finally, if you are registered with the Journal of the American Medical Association ( JAMA ), ( http://ugi.usersguides.org/usersguides/hg/hh_logon.asp? ) you will have access to the User Guide to Medical Literature. This is a good text about CA made available online, and is unlikely to leave any of your questions unanswered. Access is also allowed to fellows, members, and registered trainees of the Royal College of Obstetricians and Gynaecologists (RCOG) ( www.rcog.org.uk ). To gain access you must go to the secure site, then to information services, straight to E journals, look for the JAMA shortcut, and then obtain a user-name and password.

Critical Appraisal: Assessing the Quality of Studies

• First Online: 05 August 2020

Cite this chapter

• Edward Purssell   ORCID: orcid.org/0000-0003-3748-0864 3 &
• Niall McCrae   ORCID: orcid.org/0000-0001-9776-7694 4  

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There is great variation in the type and quality of research evidence. Having completed your search and assembled your studies, the next step is to critically appraise the studies to ascertain their quality. Ultimately you will be making a judgement about the overall evidence, but that comes later. You will see throughout this chapter that we make a clear differentiation between the individual studies and what we call the body of evidence , which is all of the studies and anything else that we use to answer the question or to make a recommendation. This chapter deals with only the first of these—the individual studies. Critical appraisal, like everything else in systematic literature reviewing, is a scientific exercise that requires individual judgement, and we describe some tools to help you.

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Purssell, E., McCrae, N. (2020). Critical Appraisal: Assessing the Quality of Studies. In: How to Perform a Systematic Literature Review. Springer, Cham. https://doi.org/10.1007/978-3-030-49672-2_6

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• Dissecting the literature: the importance of critical appraisal

08 Dec 2017

Kirsty Morrison

This post was updated  in 2023.

Critical appraisal is the process of carefully and systematically examining research to judge its trustworthiness, and its value and relevance in a particular context.

Amanda Burls, What is Critical Appraisal?

Why is critical appraisal needed?

Literature searches using databases like Medline or EMBASE often result in an overwhelming volume of results which can vary in quality. Similarly, those who browse medical literature for the purposes of CPD or in response to a clinical query will know that there are vast amounts of content available. Critical appraisal helps to reduce the burden and allow you to focus on articles that are relevant to the research question, and that can reliably support or refute its claims with high-quality evidence, or identify high-level research relevant to your practice.

Critical appraisal allows us to:

• reduce information overload by eliminating irrelevant or weak studies
• identify the most relevant papers
• distinguish evidence from opinion, assumptions, misreporting, and belief
• assess the validity of the study
• assess the usefulness and clinical applicability of the study
• recognise any potential for bias.

Critical appraisal helps to separate what is significant from what is not. One way we use critical appraisal in the Library is to prioritise the most clinically relevant content for our Current Awareness Updates .

How to critically appraise a paper

There are some general rules to help you, including a range of checklists highlighted at the end of this blog. Some key questions to consider when critically appraising a paper:

• Is the study question relevant to my field?
• Does the study add anything new to the evidence in my field?
• What type of research question is being asked? A well-developed research question usually identifies three components: the group or population of patients, the studied parameter (e.g. a therapy or clinical intervention) and outcomes of interest.
• Was the study design appropriate for the research question? You can learn more about different study types and the hierarchy of evidence here .
• Did the methodology address important potential sources of bias? Bias can be attributed to chance (e.g. random error) or to the study methods (systematic bias).
• Was the study performed according to the original protocol? Deviations from the planned protocol can affect the validity or relevance of a study, e.g. a decrease in the studied population over the course of a randomised controlled trial .
• Does the study test a stated hypothesis? Is there a clear statement of what the investigators expect the study to find which can be tested, and confirmed or refuted.
• Were the statistical analyses performed correctly? The approach to dealing with missing data, and the statistical techniques that have been applied should be specified. Original data should be presented clearly so that readers can check the statistical accuracy of the paper.
• Do the data justify the conclusions? Watch out for definite conclusions based on statistically insignificant results, generalised findings from a small sample size, and statistically significant associations being misinterpreted to imply a cause and effect.
• Are there any conflicts of interest? Who has funded the study and can we trust their objectivity? Do the authors have any potential conflicts of interest, and have these been declared?

And an important consideration for surgeons:

• Will the results help me manage my patients?

At the end of the appraisal process you should have a better appreciation of how strong the evidence is, and ultimately whether or not you should apply it to your patients.

Further resources:

• How to Read a Paper by Trisha Greenhalgh
• The Doctor’s Guide to Critical Appraisal by Narinder Kaur Gosall
• CASP checklists
• CEBM Critical Appraisal Tools
• Critical Appraisal: a checklist
• Critical Appraisal of a Journal Article (PDF)
• Introduction to...Critical appraisal of literature
• Reporting guidelines for the main study types

Kirsty Morrison, Information Specialist

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How to critically appraise an article

Affiliation.

• 1 Surgical Outcomes Research Centre, Royal Prince Alfred Hospital, Missenden Road, Sydney, NSW 2050, Australia. [email protected]
• PMID: 19153565
• DOI: 10.1038/ncpgasthep1331

Critical appraisal is a systematic process used to identify the strengths and weaknesses of a research article in order to assess the usefulness and validity of research findings. The most important components of a critical appraisal are an evaluation of the appropriateness of the study design for the research question and a careful assessment of the key methodological features of this design. Other factors that also should be considered include the suitability of the statistical methods used and their subsequent interpretation, potential conflicts of interest and the relevance of the research to one's own practice. This Review presents a 10-step guide to critical appraisal that aims to assist clinicians to identify the most relevant high-quality studies available to guide their clinical practice.

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Medicine: A Brief Guide to Critical Appraisal

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Have you ever seen a news piece about a scientific breakthrough and wondered how accurate the reporting is? Or wondered about the research behind the headlines? This is the beginning of critical appraisal: thinking critically about what you see and hear, and asking questions to determine how much of a 'breakthrough' something really is.

The article " Is this study legit? 5 questions to ask when reading news stories of medical research " is a succinct introduction to the sorts of questions you should ask in these situations, but there's more than that when it comes to critical appraisal. Read on to learn more about this practical and crucial aspect of evidence-based practice.

What is Critical Appraisal?

Critical appraisal forms part of the process of evidence-based practice. “ Evidence-based practice across the health professions ” outlines the fives steps of this process. Critical appraisal is step three:

• Ask a question
• Access the information
• Appraise the articles found
• Apply the information

Critical appraisal is the examination of evidence to determine applicability to clinical practice. It considers (1) :

• Are the results of the study believable?
• Was the study methodologically sound?  
• What is the clinical importance of the study’s results?
• Are the findings sufficiently important? That is, are they practice-changing?  
• Are the results of the study applicable to your patient?
• Is your patient comparable to the population in the study?

Why Critically Appraise?

If practitioners hope to ‘stand on the shoulders of giants’, practicing in a manner that is responsive to the discoveries of the research community, then it makes sense for the responsible, critically thinking practitioner to consider the reliability, influence, and relevance of the evidence presented to them.

While critical thinking is valuable, it is also important to avoid treading too much into cynicism; in the words of Hoffman et al. (1):

… keep in mind that no research is perfect and that it is important not to be overly critical of research articles. An article just needs to be good enough to assist you to make a clinical decision.

How do I Critically Appraise?

Evidence-based practice is intended to be practical . To enable this, critical appraisal checklists have been developed to guide practitioners through the process in an efficient yet comprehensive manner.

Critical appraisal checklists guide the reader through the appraisal process by prompting the reader to ask certain questions of the paper they are appraising. There are many different critical appraisal checklists but the best apply certain questions based on what type of study the paper is describing. This allows for a more nuanced and appropriate appraisal. Wherever possible, choose the appraisal tool that best fits the study you are appraising.

Like many things in life, repetition builds confidence and the more you apply critical appraisal tools (like checklists) to the literature the more the process will become second nature for you and the more effective you will be.

How do I Identify Study Types?

Identifying the study type described in the paper is sometimes a harder job than it should be. Helpful papers spell out the study type in the title or abstract, but not all papers are helpful in this way. As such, the critical appraiser may need to do a little work to identify what type of study they are about to critique. Again, experience builds confidence but having an understanding of the typical features of common study types certainly helps.

To assist with this, the Library has produced a guide to study designs in health research .

The following selected references will help also with understanding study types but there are also other resources in the Library’s collection and freely available online:

• The “ How to read a paper ” article series from The BMJ is a well-known source for establishing an understanding of the features of different study types; this series was subsequently adapted into a book (“ How to read a paper: the basics of evidence-based medicine ”) which offers more depth and currency than that found in the articles. (2)  
• Chapter two of “ Evidence-based practice across the health professions ” briefly outlines some study types and their application; subsequent chapters go into more detail about different study types depending on what type of question they are exploring (intervention, diagnosis, prognosis, qualitative) along with systematic reviews.  
• “ Clinical evidence made easy ” contains several chapters on different study designs and also includes critical appraisal tools. (3)  
• “ Translational research and clinical practice: basic tools for medical decision making and self-learning ” unpacks the components of a paper, explaining their purpose along with key features of different study designs. (4)  
• The BMJ website contains the contents of the fourth edition of the book “ Epidemiology for the uninitiated ”. This eBook contains chapters exploring ecological studies, longitudinal studies, case-control and cross-sectional studies, and experimental studies.

Reporting Guidelines

In order to encourage consistency and quality, authors of reports on research should follow reporting guidelines when writing their papers. The EQUATOR Network is a good source of reporting guidelines for the main study types.

While these guidelines aren't critical appraisal tools as such, they can assist by prompting you to consider whether the reporting of the research is missing important elements.

Once you've identified the study type at hand, visit EQUATOR to find the associated reporting guidelines and ask yourself: does this paper meet the guideline for its study type?

Which Checklist Should I Use?

Determining which checklist to use ultimately comes down to finding an appraisal tool that:

• Fits best with the study you are appraising
• Is reliable, well-known or otherwise validated
• You understand and are comfortable using

Below are some sources of critical appraisal tools. These have been selected as they are known to be widely accepted, easily applicable, and relevant to appraisal of a typical journal article. You may find another tool that you prefer, which is acceptable as long as it is defensible:

• CASP (Critical Appraisal Skills Programme)
• JBI (Joanna Briggs Institute)
• CEBM (Centre for Evidence-Based Medicine)
• SIGN (Scottish Intercollegiate Guidelines Network)
• STROBE (Strengthing the Reporting of Observational Studies in Epidemiology)
• BMJ Best Practice

The information on this page has been compiled by the Medical Librarian. Please contact the Library's Health Team ( [email protected] ) for further assistance.

Reference list

1. Hoffmann T, Bennett S, Del Mar C. Evidence-based practice across the health professions. 2nd ed. Chatswood, N.S.W., Australia: Elsevier Churchill Livingston; 2013.

2. Greenhalgh T. How to read a paper : the basics of evidence-based medicine. 5th ed. Chichester, West Sussex: Wiley; 2014.

3. Harris M, Jackson D, Taylor G. Clinical evidence made easy. Oxfordshire, England: Scion Publishing; 2014.

4. Aronoff SC. Translational research and clinical practice: basic tools for medical decision making and self-learning. New York: Oxford University Press; 2011.

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Risk of Bias of Individual Studies

““Assessment of risk of bias is a key step that informs many other steps and decisions made in conducting systematic reviews. It plays an important role in the final assessment of the strength of the evidence.” 1  

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• AMSTAR 2 The original AMSTAR was developed to assess the risk of bias in systematic reviews that included only randomized controlled trials. AMSTAR 2 was published in 2017 and allows researchers to identify high quality systematic reviews, including those based on non-randomised studies of healthcare interventions. more... less... AMSTAR 2 (A MeaSurement Tool to Assess systematic Reviews)
• ROBIS ROBIS is a tool designed specifically to assess the risk of bias in systematic reviews. The tool is completed in three phases: (1) assess relevance(optional), (2) identify concerns with the review process, and (3) judge risk of bias in the review. Signaling questions are included to help assess specific concerns about potential biases with the review. more... less... ROBIS (Risk of Bias in Systematic Reviews)
• BMJ Framework for Assessing Systematic Reviews This framework provides a checklist that is used to evaluate the quality of a systematic review.
• CASP Checklist for Systematic Reviews This CASP checklist is not a scoring system, but rather a method of appraising systematic reviews by considering: 1. Are the results of the study valid? 2. What are the results? 3. Will the results help locally? more... less... CASP (Critical Appraisal Skills Programme)
• CEBM Systematic Reviews Critical Appraisal Sheet The CEBM’s critical appraisal sheets are designed to help you appraise the reliability, importance, and applicability of clinical evidence. more... less... CEBM (Centre for Evidence-Based Medicine)
• JBI Critical Appraisal Tools, Checklist for Systematic Reviews JBI Critical Appraisal Tools help you assess the methodological quality of a study and to determine the extent to which study has addressed the possibility of bias in its design, conduct and analysis.
• NHLBI Study Quality Assessment of Systematic Reviews and Meta-Analyses The NHLBI’s quality assessment tools were designed to assist reviewers in focusing on concepts that are key for critical appraisal of the internal validity of a study. more... less... NHLBI (National Heart, Lung, and Blood Institute)
• RoB 2 RoB 2 provides a framework for assessing the risk of bias in a single estimate of an intervention effect reported from a randomized trial, rather than the entire trial. more... less... RoB 2 (revised tool to assess Risk of Bias in randomized trials)
• CASP Randomised Controlled Trials Checklist This CASP checklist considers various aspects of an RCT that require critical appraisal: 1. Is the basic study design valid for a randomized controlled trial? 2. Was the study methodologically sound? 3. What are the results? 4. Will the results help locally? more... less... CASP (Critical Appraisal Skills Programme)
• CONSORT Statement The CONSORT checklist includes 25 items to determine the quality of randomized controlled trials. Critical appraisal of the quality of clinical trials is possible only if the design, conduct, and analysis of RCTs are thoroughly and accurately described in the report. more... less... CONSORT (Consolidated Standards of Reporting Trials)
• NHLBI Study Quality Assessment of Controlled Intervention Studies The NHLBI’s quality assessment tools were designed to assist reviewers in focusing on concepts that are key for critical appraisal of the internal validity of a study. more... less... NHLBI (National Heart, Lung, and Blood Institute)
• JBI Critical Appraisal Tools Checklist for Randomized Controlled Trials JBI Critical Appraisal Tools help you assess the methodological quality of a study and to determine the extent to which study has addressed the possibility of bias in its design, conduct and analysis.
• ROBINS-I ROBINS-I is a tool for evaluating risk of bias in estimates of the comparative effectiveness… of interventions from studies that did not use randomization to allocate units to comparison groups. more... less... ROBINS-I (Risk Of Bias in Non-randomized Studies – of Interventions)
• NOS This tool is used primarily to evaluate and appraise case-control or cohort studies. more... less... NOS (Newcastle-Ottawa Scale)
• AXIS Cross-sectional studies are frequently used as an evidence base for diagnostic testing, risk factors for disease, and prevalence studies. The AXIS tool focuses mainly on the presented study methods and results. more... less... AXIS (Appraisal tool for Cross-Sectional Studies)
• NHLBI Study Quality Assessment Tools for Non-Randomized Studies The NHLBI’s quality assessment tools were designed to assist reviewers in focusing on concepts that are key for critical appraisal of the internal validity of a study. • Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies • Quality Assessment of Case-Control Studies • Quality Assessment Tool for Before-After (Pre-Post) Studies With No Control Group • Quality Assessment Tool for Case Series Studies more... less... NHLBI (National Heart, Lung, and Blood Institute)
• Case Series Studies Quality Appraisal Checklist Developed by the Institute of Health Economics (Canada), the checklist is comprised of 20 questions to assess the robustness of the evidence of uncontrolled case series studies.
• Methodological Quality and Synthesis of Case Series and Case Reports In this paper, Dr. Murad and colleagues present a framework for appraisal, synthesis and application of evidence derived from case reports and case series.
• MINORS The MINORS instrument contains 12 items and was developed for evaluating the quality of observational or non-randomized studies. This tool may be of particular interest to researchers who would like to critically appraise surgical studies. more... less... MINORS (Methodological Index for Non-Randomized Studies)
• JBI Critical Appraisal Tools for Non-Randomized Trials JBI Critical Appraisal Tools help you assess the methodological quality of a study and to determine the extent to which study has addressed the possibility of bias in its design, conduct and analysis. • Checklist for Analytical Cross Sectional Studies • Checklist for Case Control Studies • Checklist for Case Reports • Checklist for Case Series • Checklist for Cohort Studies
• QUADAS-2 The QUADAS-2 tool is designed to assess the quality of primary diagnostic accuracy studies it consists of 4 key domains that discuss patient selection, index test, reference standard, and flow of patients through the study and timing of the index tests and reference standard. more... less... QUADAS-2 (a revised tool for the Quality Assessment of Diagnostic Accuracy Studies)
• JBI Critical Appraisal Tools Checklist for Diagnostic Test Accuracy Studies JBI Critical Appraisal Tools help you assess the methodological quality of a study and to determine the extent to which study has addressed the possibility of bias in its design, conduct and analysis.
• STARD 2015 The authors of the standards note that essential elements of diagnostic accuracy study methods are often poorly described and sometimes completely omitted, making both critical appraisal and replication difficult, if not impossible. The Standards for the Reporting of Diagnostic Accuracy Studies was developed to help improve completeness and transparency in reporting of diagnostic accuracy studies. more... less... STARD 2015 (Standards for the Reporting of Diagnostic Accuracy Studies)
• CASP Diagnostic Study Checklist This CASP checklist considers various aspects of diagnostic test studies including: 1. Are the results of the study valid? 2. What were the results? 3. Will the results help locally? more... less... CASP (Critical Appraisal Skills Programme)
• CEBM Diagnostic Critical Appraisal Sheet The CEBM’s critical appraisal sheets are designed to help you appraise the reliability, importance, and applicability of clinical evidence. more... less... CEBM (Centre for Evidence-Based Medicine)
• SYRCLE’s RoB Implementation of SYRCLE’s RoB tool will facilitate and improve critical appraisal of evidence from animal studies. This may enhance the efficiency of translating animal research into clinical practice and increase awareness of the necessity of improving the methodological quality of animal studies. more... less... SYRCLE’s RoB (SYstematic Review Center for Laboratory animal Experimentation’s Risk of Bias)
• ARRIVE 2.0 The ARRIVE 2.0 guidelines are a checklist of information to include in a manuscript to ensure that publications on in vivo animal studies contain enough information to add to the knowledge base. more... less... ARRIVE 2.0 (Animal Research: Reporting of In Vivo Experiments)
• Critical Appraisal of Studies Using Laboratory Animal Models This article provides an approach to critically appraising papers based on the results of laboratory animal experiments, and discusses various bias domains in the literature that critical appraisal can identify.
• CEBM Critical Appraisal of Qualitative Studies Sheet The CEBM’s critical appraisal sheets are designed to help you appraise the reliability, importance and applicability of clinical evidence. more... less... CEBM (Centre for Evidence-Based Medicine)
• CASP Qualitative Studies Checklist This CASP checklist considers various aspects of qualitative research studies including: 1. Are the results of the study valid? 2. What were the results? 3. Will the results help locally? more... less... CASP (Critical Appraisal Skills Programme)
• Quality Assessment and Risk of Bias Tool Repository Created by librarians at Duke University, this extensive listing contains over 100 commonly used risk of bias tools that may be sorted by study type.
• Latitudes Network A library of risk of bias tools for use in evidence syntheses that provides selection help and training videos.

References & Recommended Reading

1.    Viswanathan, M., Patnode, C. D., Berkman, N. D., Bass, E. B., Chang, S., Hartling, L., ... & Kane, R. L. (2018). Recommendations for assessing the risk of bias in systematic reviews of health-care interventions .  Journal of clinical epidemiology ,  97 , 26-34.

2.     Kolaski, K., Logan, L. R., & Ioannidis, J. P. (2024). Guidance to best tools and practices for systematic reviews .  British Journal of Pharmacology ,  181 (1), 180-210

3.     Fowkes FG, Fulton PM.  Critical appraisal of published research: introductory guidelines.   BMJ (Clinical research ed).  1991;302(6785):1136-1140.

4.     Shea BJ, Reeves BC, Wells G, et al.  AMSTAR 2: a critical appraisal tool for systematic reviews that include randomised or non-randomised studies of healthcare interventions, or both.   BMJ (Clinical research ed).  2017;358:j4008.

5..     Whiting P, Savovic J, Higgins JPT, et al.  ROBIS: A new tool to assess risk of bias in systematic reviews was developed.   Journal of clinical epidemiology.  2016;69:225-234.

6.     Sterne JAC, Savovic J, Page MJ, et al.  RoB 2: a revised tool for assessing risk of bias in randomised trials.  BMJ (Clinical research ed).  2019;366:l4898.

7.     Moher D, Hopewell S, Schulz KF, et al.  CONSORT 2010 Explanation and Elaboration: Updated guidelines for reporting parallel group randomised trials.  Journal of clinical epidemiology.  2010;63(8):e1-37.

8..    Sterne JA, Hernan MA, Reeves BC, et al.  ROBINS-I: a tool for assessing risk of bias in non-randomised studies of interventions.  BMJ (Clinical research ed).  2016;355:i4919.

9.    Downes MJ, Brennan ML, Williams HC, Dean RS.  Development of a critical appraisal tool to assess the quality of cross-sectional studies (AXIS).   BMJ open.  2016;6(12):e011458.

10.   Guo B, Moga C, Harstall C, Schopflocher D.  A principal component analysis is conducted for a case series quality appraisal checklist.   Journal of clinical epidemiology.  2016;69:199-207.e192.

11.   Murad MH, Sultan S, Haffar S, Bazerbachi F.  Methodological quality and synthesis of case series and case reports.  BMJ evidence-based medicine.  2018;23(2):60-63.

12.   Slim K, Nini E, Forestier D, Kwiatkowski F, Panis Y, Chipponi J.  Methodological index for non-randomized studies (MINORS): development and validation of a new instrument.   ANZ journal of surgery.  2003;73(9):712-716.

13.   Whiting PF, Rutjes AWS, Westwood ME, et al.  QUADAS-2: a revised tool for the quality assessment of diagnostic accuracy studies.   Annals of internal medicine.  2011;155(8):529-536.

14.   Bossuyt PM, Reitsma JB, Bruns DE, et al.  STARD 2015: an updated list of essential items for reporting diagnostic accuracy studies.   BMJ (Clinical research ed).  2015;351:h5527.

15.   Hooijmans CR, Rovers MM, de Vries RBM, Leenaars M, Ritskes-Hoitinga M, Langendam MW.  SYRCLE's risk of bias tool for animal studies.   BMC medical research methodology.  2014;14:43.

16.   Percie du Sert N, Ahluwalia A, Alam S, et al.  Reporting animal research: Explanation and elaboration for the ARRIVE guidelines 2.0.  PLoS biology.  2020;18(7):e3000411.

17.   O'Connor AM, Sargeant JM.  Critical appraisal of studies using laboratory animal models.   ILAR journal.  2014;55(3):405-417.

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Introduction to critical appraisal and evaluation

The information you use in your research and study must all be credible, reliable and relevant. Part of the Evidence-Based Practice process is to critically appraise scientific papers, but in general, all the resources you refer to should be evaluated carefully to ensure their credibility.

How can you tell whether the resources you've found are credible and suitable for you to reference? To evaluate Information you have found on websites, see the video below and the box on using Internet sites. Journal articles and academic texts should at least have gone through a process of peer review (see the video about peer review on the Journals page of this guide).

Critical appraisal of scientific papers takes the evaluation to another level. Once you have asked the clinical question and searched for evidence, it's often not enough that you've checked for peer review if you want to find the very best evidence - it will ensure that studies with scientific flaws are disregarded, and the ones you include are relevant to your question.

In the Evidence-Based Practice process, and especially in the process of evaluating primary research (which hasn't been pre-appraised or filtered by others), we need to go beyond the usual general information evaluation and make sure the evidence we are using is scientifically rigorous. The main questions to address are:

• Is the study relevant to your clinical question?
• How well (scientifically) was the study done, especially taking care to eliminate bias?
• What do the results mean and are they statistically valid (and not just due to chance)?

For a more detailed look at Critical Appraisal, head to the Systematic Review Guide - Critical Appraisal and the Evidence-Based Practice Guide - Appraise.

Critical appraisal tools

Fortunately, there have been some great checklist tools developed for different types of studies. Here are some examples:

• The Joanna Briggs Institute (JBI) provides access to critical appraisal tools, a collection of checklists that you can use to help you appraise or evaluate research.
• Critical Appraisal Skills Programme (CASP) is part of Better Value Healthcare based in Oxford, UK. It includes a series of checklists , suitable for different types of studies and designed to be used when reading research.
• The Equator Network is devoted to Enhancing the QUAlity and Transparency Of health Research. Among other functions, they include a  Toolkit for Peer Reviewing Health Research   which is very useful as a guide for critically appraising studies.
• Critical Appraisal Tools (CEBM)  - This site from the Centre of Evidence Based Medicine includes tools and worksheets for the critical appraisal of different types of medical evidence.
• Understanding Health Research - is from the Medical Research Council in the UK. It's a very handy all-purpose tool which takes you through a series of questions about a particular article, highlighting the good points and possible problem areas. You can print off a summary at the end of your checklist

Critical appraisal tools from the NHS in Scotland links interactively to all sorts of resources on how to identify the study type and build your critical appraisal skills, as well as to tools themselves.

Critical reading and understanding research

A useful series of articles for nurses about critiquing and understanding types of research has been published in the Australian Journal of Advanced Nursing by Rebecca Ingham-Broomfield, from the University of New South Wales:

Ingham-Broomfield, R. (2014). A nurses' guide to the critical reading of research . Australian Journal of Advanced Nursing , 32 (1), 37-44. [Updated from 2008.]

Ingham-Broomfield, R. (2014). A nurses' guide to quantitative research . Australian Journal of Advanced Nursing, 32 (2), 32-38. 

Ingham-Broomfield, R. (2015). A nurses' guide to qualitative research . Australian Journal of Advanced Nursing, 32 (3), 34-40. 

Ingham-Broomfield, R. (2016). A nurses' guide to mixed methods research . Australian Journal of Advanced Nursing, 33 (4), 46-52. 

Ingham-Broomfield, R. (2016). A nurses' guide to the hierarchy of research designs and evidence . The Australian Journal of Advanced Nursing, 33 (3), 38-43. 

Evaluate internet resources

The website domain gives you an idea of the reliability of a website:

Critical appraisal resources

Introduction to Critical Appraisal -  This short video from the library at the University of Sheffield in the UK looks at the background to critical appraisal, what it is, and why we do it. A very useful introduction to the topic.

Evaluating information

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Understanding research and critical appraisal

• Introduction
• Secondary research
• Primary research

The need for critical appraisal

Critical appraisal checklists, critical appraisal for anti-racism.

• Useful terminology
• Further reading and helpful resources

Why critical appraisal?

As noted earlier, research studies can vary in methodological quality, and critical appraisal provides a means to consistently evaluate the validity, reliability and relevance of research results. 

The purpose of critical appraisal is not to criticise a paper, but to appraise the methodology for any factors which could impact upon the findings. Below are some initial questions to ask of a paper when you set about reading it. 

• What is the research question?
• Why was the research needed?
• What type of study design was used?
• Was the study design appropriate for answering the research question?

The answers to these questions will typically be found in the abstract, the introduction or the methods section of a paper, and should offer an initial sense of the study.

Critical appraisal will help to determine the validity of a study in two important ways.  Internal validity relates to the reliability and accuracy of research results, effected by the appropriateness of the research methods used to address the research question, and the extent to which a study measures what it sets out to measure.  E xternal validity  relates to the extent to which research results are generalisable to populations beyond the study participants.

Participants

Depending on the study design used, there are various details relating to research participants that should be included in a paper. These might be, for example: how the participants were recruited, demographic and other relevant characteristics of the study participants, how participants were assigned to study groups, how many participants took part, and how many participants (if any) dropped out before the end of the study.

Confounding

Many research studies aim to establish an association between a treatment or exposure, and an outcome. A confounding factor is any factor which might influence the association of the two, either suggesting an association where none exists (or distorting the nature of the association), or masking a true association, and leading to incorrect conclusions. Confounding factors might include demographic characteristics of participants, such as age or gender, or lifestyle factors such as diet or exercise.

Researchers should take steps to identify potential confounding factors which might influence a study, and control these, either through the design of the study, or through statistical analysis of the research data.

There are various forms of bias which may be introduced into research at various points during a study, and effect the accuracy of the study findings. Researchers should be aware of any potential biases in relation to their study, and take steps to avoid these, and as readers, we should be also be aware of the relevant biases and the measures which might be taken to avoid or minimise their impact. 

Below are some potential biases which can effect research findings, or the application of research evidence to practice. For a comprehensive list of biases, see the Catalogue of Bias website .

Selection bias is introduced when the participants in a study have some systematically different characteristic to those not under study. This bias can also be introduced if there is some systematic difference between participants in the treatment group, and those in the control group. When reading a paper, look for details on the number of participants screened and included, the randomisation procedure used (if applicable), baseline comparisons of study groups, and procedures for handling any missing data.

Observer bias  is introduced when there are differences between the observations or assessments made by researchers and the true values of such observations. When a study is collecting subjective data, observer bias might occur owing to the beliefs, values or perspective of the researcher(s). When a study is collecting objective data, observer bias might occur owing to different practices in the interpretation or recording of data. Blinding of those researchers who are to assess outcomes can help, where applicable, as can researcher acknowledgement of the potential impact of their bias(es).

Attrition bias  is introduced when those participants who drop out of a study differ in some systematic way from the participants who complete the study. Attrition bias can distort the findings of a study, leading to incorrect assumptions about the effect of a treatment, for example. When reading a paper, look for information on how participant data was analysed, and for information on the number of participants lost and their reasons for leaving the study.

Reporting bias  is introduced when researchers selectively report - or suppress - relevant data or information from a study. Reporting bias might arise from researchers withholding relevant conflicts of interest, changing study outcomes to fit data, over-reporting potential benefits or under-reporting potential harms.

Publication bias  is a form of reporting bias, which results from non-publication of research studies which produce either negative or insubstantial findings. The absence of this research data can lead to the distortion of the full body of evidence on a subject, where only positive findings are published. The registration and reporting of clinical trials in trial registries allows access to some of this data, but this is reliant on researchers complying with requirements. Systematic reviews and meta-analyses can also play a part in reducing the impact of publication bias, by going beyond published journal articles when collecting their data sources, and by employing appropriate statistical methods to assess for publication bias.

Two very commonly reported statistical calculations of the results of a trial are the  p-value  and the  confidence interval (CI) .

The  p-value  indicates the probability of any given outcome arising through chance. A smaller p-value equates to a smaller likelihood of the outcome occurring by chance, and the conventional cut off point for a statistically significant p-value is 0.05 or less (equivalent to a probability of 1 in 20 or less).

The  confidence interval  is a statistical range within which the true effect or result of a study lies, and is a means for researchers to convey their confidence in their findings. The convention is to state the 95% confidence interval, which is the range within which true results would lie on 95% of occasions.

As research studies involve only sample populations, reporting the p-value and/or CI can help to statistically generalise the applicability of research findings from the study participants to the overall population. In both cases, however, it is important to note that a smaller study sample population offers less certainty in the ability to generalise findings.

Significance

A research study might produce findings which have  statistical significance  or  clinical significant , or both. The p-value and/or CI reported in a study can help determine the statistical significance of results, while the clinical significance of a study relates to whether the findings translate to worthwhile or noticeable improvements for a real population. 

It is important to bear in mind that findings which are not statistically significant may have clinical significance.

Further statistical measures of clinical effectiveness

For further information on common statistical terms and concepts you will encounter when appraising papers such as odds, odd ratios, risk, risk ratios and numbers needed to treat, you will find a number of helpful articles here:

  AKT Statistics Topics – Dr Chris Cates' EBM Website (nntonline.net)

The below sites host checklists which can be used to help appraise the reliability and applicability of publications, ranging from peer-reviewed articles to grey literature

• Amstar systematic review checklist AMSTAR (A MeaSurement Tool to Assess systematic Reviews) can be used to assess the methodological quality of a systematic review and as a guide to performing a systematic review. Two agreements are required during quality assessment ensuring lower risk of bias. AMSTAR has guidelines explaining each outlined item
• CASP Appraisal Checklists This set of eight critical appraisal tools are designed to be used when reading research, these include tools for Systematic Reviews, Randomised Controlled Trials, Cohort Studies, Case Control Studies, Economic Evaluations, Diagnostic Studies, Qualitative studies and Clinical Prediction Rule.
• Critical Appraisal tools A series of critical appraisal worksheets for different types of research studies, from the Oxford Centre for Evidence Based Medicine (CEBM) - including versions in multiple languages
• Critical Appraisal Tools Critical appraisal checklists for a broad range of research study types, from the Joanna Briggs Institute
• SIGN checklists These checklists were subjected to evaluation and adaptation to meet the Scottish Intercollegiate Guidelines Network's (SIGN’s) requirements for a balance between methodological rigour and practicality of use.
• Mixed Methods Appraisal Tool (MMAT) The MMAT is intended to be used as a checklist for concomitantly appraising and/or describing studies included in systematic mixed studies reviews (reviews including original qualitative, quantitative and mixed methods studies).
• AACODS grey literature checklist The AACODS checklist is a tool for evaluating the Authority, Accuracy, Coverage, Objective, Date and Significance of grey literature.

Traditional appraisal tools do not prompt appraisers to look into questions around racial under-representation in research and racial bias in interpretation of findings with regards to minoritised ethnic groups in medical research. In order to combat this, librarian and information specialist, Ramona Naicker , has developed a supplementary tool that can be used to address these issues.

Watch the video below for an outline of the issues and how the checklist can be used.

• << Previous: Primary research
• Next: Useful terminology >>
• Last Updated: Mar 26, 2024 4:38 PM
• URL: https://libguides.sgul.ac.uk/researchdesign

• DOI: 10.1111/apt.18156
• Corpus ID: 271531455

Letter: Critical appraisal of biologic therapy in management of early ulcerative colitis-Addressing study limitations and the role of psychological resilience.

• Qing Lan , Long Guo , Zhifan Xiong
• Published in Alimentary Pharmacology and… 28 July 2024
• Medicine, Psychology

One Citation

Letter: critical appraisal of biologic therapy in early ulcerative colitis management-addressing study limitations and the role of psychological resilience-authors' reply., 5 references, evaluating clinical, dietary, and psychological risk factors for relapse of ulcerative colitis in clinical, endoscopic, and histological remission, clinical course of ulcerative colitis: frequent use of biologics and low colectomy rate first year after diagnosis-results from the ibsen iii inception cohort., environmental risk factors for inflammatory bowel diseases: an umbrella review of meta-analyses., use of complementary and alternative medicine and low quality of life associate with the need for psychological and psychotherapeutic interventions in inflammatory bowel disease, development of a new resilience scale: the connor‐davidson resilience scale (cd‐risc), related papers.

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Land use changes in the environs of Moscow

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How to cite ChatGPT

Use discount code STYLEBLOG15 for 15% off APA Style print products with free shipping in the United States.

We, the APA Style team, are not robots. We can all pass a CAPTCHA test , and we know our roles in a Turing test . And, like so many nonrobot human beings this year, we’ve spent a fair amount of time reading, learning, and thinking about issues related to large language models, artificial intelligence (AI), AI-generated text, and specifically ChatGPT . We’ve also been gathering opinions and feedback about the use and citation of ChatGPT. Thank you to everyone who has contributed and shared ideas, opinions, research, and feedback.

In this post, I discuss situations where students and researchers use ChatGPT to create text and to facilitate their research, not to write the full text of their paper or manuscript. We know instructors have differing opinions about how or even whether students should use ChatGPT, and we’ll be continuing to collect feedback about instructor and student questions. As always, defer to instructor guidelines when writing student papers. For more about guidelines and policies about student and author use of ChatGPT, see the last section of this post.

Quoting or reproducing the text created by ChatGPT in your paper

If you’ve used ChatGPT or other AI tools in your research, describe how you used the tool in your Method section or in a comparable section of your paper. For literature reviews or other types of essays or response or reaction papers, you might describe how you used the tool in your introduction. In your text, provide the prompt you used and then any portion of the relevant text that was generated in response.

Unfortunately, the results of a ChatGPT “chat” are not retrievable by other readers, and although nonretrievable data or quotations in APA Style papers are usually cited as personal communications , with ChatGPT-generated text there is no person communicating. Quoting ChatGPT’s text from a chat session is therefore more like sharing an algorithm’s output; thus, credit the author of the algorithm with a reference list entry and the corresponding in-text citation.

When prompted with “Is the left brain right brain divide real or a metaphor?” the ChatGPT-generated text indicated that although the two brain hemispheres are somewhat specialized, “the notation that people can be characterized as ‘left-brained’ or ‘right-brained’ is considered to be an oversimplification and a popular myth” (OpenAI, 2023).

OpenAI. (2023). ChatGPT (Mar 14 version) [Large language model]. https://chat.openai.com/chat

You may also put the full text of long responses from ChatGPT in an appendix of your paper or in online supplemental materials, so readers have access to the exact text that was generated. It is particularly important to document the exact text created because ChatGPT will generate a unique response in each chat session, even if given the same prompt. If you create appendices or supplemental materials, remember that each should be called out at least once in the body of your APA Style paper.

When given a follow-up prompt of “What is a more accurate representation?” the ChatGPT-generated text indicated that “different brain regions work together to support various cognitive processes” and “the functional specialization of different regions can change in response to experience and environmental factors” (OpenAI, 2023; see Appendix A for the full transcript).

Creating a reference to ChatGPT or other AI models and software

The in-text citations and references above are adapted from the reference template for software in Section 10.10 of the Publication Manual (American Psychological Association, 2020, Chapter 10). Although here we focus on ChatGPT, because these guidelines are based on the software template, they can be adapted to note the use of other large language models (e.g., Bard), algorithms, and similar software.

The reference and in-text citations for ChatGPT are formatted as follows:

• Parenthetical citation: (OpenAI, 2023)
• Narrative citation: OpenAI (2023)

Let’s break that reference down and look at the four elements (author, date, title, and source):

Author: The author of the model is OpenAI.

Date: The date is the year of the version you used. Following the template in Section 10.10, you need to include only the year, not the exact date. The version number provides the specific date information a reader might need.

Title: The name of the model is “ChatGPT,” so that serves as the title and is italicized in your reference, as shown in the template. Although OpenAI labels unique iterations (i.e., ChatGPT-3, ChatGPT-4), they are using “ChatGPT” as the general name of the model, with updates identified with version numbers.

The version number is included after the title in parentheses. The format for the version number in ChatGPT references includes the date because that is how OpenAI is labeling the versions. Different large language models or software might use different version numbering; use the version number in the format the author or publisher provides, which may be a numbering system (e.g., Version 2.0) or other methods.

Bracketed text is used in references for additional descriptions when they are needed to help a reader understand what’s being cited. References for a number of common sources, such as journal articles and books, do not include bracketed descriptions, but things outside of the typical peer-reviewed system often do. In the case of a reference for ChatGPT, provide the descriptor “Large language model” in square brackets. OpenAI describes ChatGPT-4 as a “large multimodal model,” so that description may be provided instead if you are using ChatGPT-4. Later versions and software or models from other companies may need different descriptions, based on how the publishers describe the model. The goal of the bracketed text is to briefly describe the kind of model to your reader.

Source: When the publisher name and the author name are the same, do not repeat the publisher name in the source element of the reference, and move directly to the URL. This is the case for ChatGPT. The URL for ChatGPT is https://chat.openai.com/chat . For other models or products for which you may create a reference, use the URL that links as directly as possible to the source (i.e., the page where you can access the model, not the publisher’s homepage).

Other questions about citing ChatGPT

You may have noticed the confidence with which ChatGPT described the ideas of brain lateralization and how the brain operates, without citing any sources. I asked for a list of sources to support those claims and ChatGPT provided five references—four of which I was able to find online. The fifth does not seem to be a real article; the digital object identifier given for that reference belongs to a different article, and I was not able to find any article with the authors, date, title, and source details that ChatGPT provided. Authors using ChatGPT or similar AI tools for research should consider making this scrutiny of the primary sources a standard process. If the sources are real, accurate, and relevant, it may be better to read those original sources to learn from that research and paraphrase or quote from those articles, as applicable, than to use the model’s interpretation of them.

We’ve also received a number of other questions about ChatGPT. Should students be allowed to use it? What guidelines should instructors create for students using AI? Does using AI-generated text constitute plagiarism? Should authors who use ChatGPT credit ChatGPT or OpenAI in their byline? What are the copyright implications ?

On these questions, researchers, editors, instructors, and others are actively debating and creating parameters and guidelines. Many of you have sent us feedback, and we encourage you to continue to do so in the comments below. We will also study the policies and procedures being established by instructors, publishers, and academic institutions, with a goal of creating guidelines that reflect the many real-world applications of AI-generated text.

For questions about manuscript byline credit, plagiarism, and related ChatGPT and AI topics, the APA Style team is seeking the recommendations of APA Journals editors. APA Style guidelines based on those recommendations will be posted on this blog and on the APA Style site later this year.

Update: APA Journals has published policies on the use of generative AI in scholarly materials .

We, the APA Style team humans, appreciate your patience as we navigate these unique challenges and new ways of thinking about how authors, researchers, and students learn, write, and work with new technologies.

American Psychological Association. (2020). Publication manual of the American Psychological Association (7th ed.). https://doi.org/10.1037/0000165-000

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Shchyolkovo , city and centre of a rayon (sector), Moscow oblast (region), western Russia . It lies along the Klyazma River a few miles northeast of Moscow. Shchyolkovo was renowned from the 18th century as a centre of handicraft silk weaving , and today it remains a centre of various textile industries. The city also has important chemical, metalworking, and engineering industries. Pop. (2006 est.) 112,860.