critical appraisal assignment examples

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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Critical Appraisal for Health Students

• Critical Appraisal of a quantitative paper
• Critical Appraisal: Help
• Critical Appraisal of a qualitative paper
• Useful resources

Appraisal of a Quantitative paper: Top tips

• Introduction

Critical appraisal of a quantitative paper (RCT)

This guide, aimed at health students, provides basic level support for appraising quantitative research papers. It's designed for students who have already attended lectures on critical appraisal. One framework for appraising quantitative research (based on reliability, internal and external validity) is provided and there is an opportunity to practise the technique on a sample article.

Please note this framework is for appraising one particular type of quantitative research a Randomised Controlled Trial (RCT) which is defined as 

a trial in which participants are randomly assigned to one of two or more groups: the experimental group or groups receive the intervention or interventions being tested; the comparison group (control group) receive usual care or no treatment or a placebo.  The groups are then followed up to see if there are any differences between the results.  This helps in assessing the effectiveness of the intervention.(CASP, 2020)

Support materials

• Framework for reading quantitative papers (RCTs)
• Critical appraisal of a quantitative paper PowerPoint

To practise following this framework for critically appraising a quantitative article, please look at the following article:

Marrero, D.G.  et al  (2016) 'Comparison of commercial and self-initiated weight loss programs in people with prediabetes: a randomized control trial',  AJPH Research , 106(5), pp. 949-956.

Critical Appraisal of a quantitative paper (RCT): practical example

• Internal Validity
• External Validity
• Reliability Measurement Tool

How to use this practical example 

Using the framework, you can have a go at appraising a quantitative paper - we are going to look at the following article:

Marrero, d.g.  et al  (2016) 'comparison of commercial and self-initiated weight loss programs in people with prediabetes: a randomized control trial',  ajph research , 106(5), pp. 949-956.,            step 1.  take a quick look at the article, step 2.  click on the internal validity tab above - there are questions to help you appraise the article, read the questions and look for the answers in the article. , step 3.   click on each question and our answers will appear., step 4.    repeat with the other aspects of external validity and reliability. , questioning the internal validity:, randomisation : how were participants allocated to each group did a randomisation process taken place, comparability of groups: how similar were the groups eg age, sex, ethnicity – is this made clear, blinding (none, single, double or triple): who was not aware of which group a patient was in (eg nobody, only patient, patient and clinician, patient, clinician and researcher) was it feasible for more blinding to have taken place , equal treatment of groups: were both groups treated in the same way , attrition : what percentage of participants dropped out did this adversely affect one group has this been evaluated, overall internal validity: does the research measure what it is supposed to be measuring, questioning the external validity:, attrition: was everyone accounted for at the end of the study was any attempt made to contact drop-outs, sampling approach: how was the sample selected was it based on probability or non-probability what was the approach (eg simple random, convenience) was this an appropriate approach, sample size (power calculation): how many participants was a sample size calculation performed did the study pass, exclusion/ inclusion criteria: were the criteria set out clearly were they based on recognised diagnostic criteria, what is the overall external validity can the results be applied to the wider population, questioning the reliability (measurement tool) internal validity:, internal consistency reliability (cronbach’s alpha). has a cronbach’s alpha score of 0.7 or above been included, test re-test reliability correlation. was the test repeated more than once were the same results received has a correlation coefficient been reported is it above 0.7 , validity of measurement tool. is it an established tool if not what has been done to check if it is reliable pilot study expert panel literature review criterion validity (test against other tools): has a criterion validity comparison been carried out was the score above 0.7, what is the overall reliability how consistent are the measurements , overall validity and reliability:, overall how valid and reliable is the paper.

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Occupational Therapy and Rehabilitation Sciences

• Defining the Research Question(s)
• Reference Resources
• Evidence Summaries & Clinical Guidelines
• Health Data & Statistics
• Patient & Consumer Facing Materials
• Images/Streaming Video
• Database Tutorials
• Crafting a Search
• Narrowing / Filtering a Search
• Expanding a Search
• Cited Reference Searching
• Find Grey Literature
• Save Your Searches
• Cite Sources
• Critical Appraisal
• Different Types of Literature Reviews
• Conducting & Reporting Systematic Reviews
• Finding Systematic Reviews
• Tutorials & Tools for Literature Reviews
• Mobile Apps for Health

PRISMA  or Preferred Reporting Items for Systematic Reviews and Meta-Analyses is an evidence-based protocol for reporting information in systematic reviews and meta-analyses.

• The PRISMA STATEMENT , a 27-item checklist and a four-phase flow diagram to help authors improve the reporting of systematic reviews and meta-analyses.
• PRISMA also offers editable templates for the flow diagram as PDF and Word documents 

Appraising the Evidence: Getting Started

To appraise the quality of evidence, it is essential understand the nature of the evidence source. Begin the appraisal process by considering these general characteristics:

• Is the source primary, secondary or tertiary? (See University of Minnesota Library -  Primary, Secondary, and Tertiary Sources in the Health Sciences )
• If the source is a journal article, what kind of article is it? (A report of original research? A review article? An opinion or commentary?)
• If the source is reporting original research, what was the purpose of the research?
• What is the date of publication?
• Would the evidence presented in the source still be applicable today? (Consider: has technology changed? Have recommended best clinical practices changed? Has consensus understanding of a disease, condition, or treatment changed?)

Authority/Accuracy

• Who is the author? What are the author's credentials and qualifications and to write on the topic?
• Was the source published by a credible entity? (a scholarly journal? a popular periodical, e.g, newspaper or magazine?  an association? an organization?)
• Did the source go through a peer review or editorial process before being published? (See this section of the guide for more information about locating peer reviewed articles)

Determining Study Methodology

Understanding how a study was conducted (the methodology) is fundamental for determining the level of evidence that was generated by the study, as well as assessing the quality of the evidence it generated.  While some papers state explicitly in the title what kind of method was used, it is often not so straightforward.  When looking at report of a study, there are a few techniques you can use to help classify the study design.

1. Notice Metadata in Database Records

In some bibliographic databases, there is information found in the Subject field, or the Publication Type field of the record that can provide information about a study's methodology.  Try to locate the record for the article of interest in CINAHL, PubMed or PsycINFO and look for information describing the study (e.g., is it tagged as a "randomized controlled trial,"  a "case report," and "observational study", a "review" article, etc).

• A word of caution : A  "review" article is not necessarily a "systematic review."  Even if the title or abstract says "systematic review," carefully evaluate what type of review it is (a systematic review of interventions? a mixed methods SR? a scoping review? a narrative review?).

2. Read the Methods Section

While there may be some information in the abstract that indicates a study's design, it is often necessary to read the full methods section in order to truly understand how the study was conducted.  For help understanding the major types of research methodologies within the health sciences, see:

• Understanding Research Study Designs  (University of Minnesota Library)
• Study Designs  (Centre for Evidence Based Medicine)
• Jeremey Howick's  Introduction to Study Designs  (Flow Chart) [PDF]
• Quantitative Study Designs  (Deakin University Library)
• Grimes, D. A., & Schulz, K. F. (2002). An overview of clinical research: the lay of the land .  Lancet (London, England) ,  359 (9300), 57–61. https://doi.org/10.1016/S0140-6736(02)07283-5
• Deconstructing the Research Article (May/Jun2022; 42(3): 138-140)
• Background, Significance, and Literature Review (Jul-Aug2022; 42(4): 203-205)
• Purpose Statement, Research Questions, and Hypotheses (Sep/Oct2022; 42(5): 249-257)
• Quantitative Research Designs (Nov/Dec2022; 42(6): 303-311)
• Qualitative Research Designs (Jan/Feb2023; 43(1): 41-45)
• Non-Experimental Research Designs (Mar/Apr2023; 43(2): 99-102)

Once the study methodology is understood, a tool or checklist can be selected to appraise the quality of the evidence that was generated by that study.  

Critical Appraisal Resources

In order to select a tool for critical appraisal (also known as quality assessment or "risk of bias" assessment), it is necessary to understand what methodology was used in the study.  (For help understanding study design, see this section of the guide .)

The list below sets of contains critical appraisal tools and checklists, with information about what types of studies those tools are meant for.  Additionally, there are links to reporting guidelines for different types of students, which can also be useful for quality assessment.  

If you're new to critical appraisal, check out this helpful video overview of some of the common tools:

Checklists & Tools

The AGREE II an instrument is valid and reliable tool that can be applied to any practice guideline in any disease area and can be used by health care providers, guideline developers, researchers, decision/policy makers, and educators.

For help using the AGREE II instrument, see the AGREE II Training Tools

• AMSTAR 2 AMSTAR 2 is the revised version of the popular AMSTAR tool (a tool for critically appraising systematic reviews of RCTs). AMSTAR 2 can be used to critically appraise systematic reviews that include randomized or non-randomized studies of healthcare interventions, or both.

A collection of checklists for a number of purposes related to EBM, including finding, interpreting, and evaluating research evidence.

Found in Appendix 1 of Greenhalgh, Trisha. (2010). How to Read a Paper : The Basics of Evidence Based Medicine, 4th edition .

Systematic reviews Randomised controlled trials Qualitative research studies Economic evaluation studies Cohort studies Case control studies Diagnostic test studies

CEBM offers Critical Appraisal Sheets for:

• GRADE The GRADE working group has developed a common, sensible and transparent approach to grading quality of a body of evidence and strength of recommendations that can be drawn from randomized and non-randomized trials . GRADE is meant for use in systematic reviews and other evidence syntheses (e.g., clinical guidelines) where a recommendation impacting practice will be made.

JBI’s critical appraisal tools assist in assessing the trustworthiness, relevance and results of published papers. There are checklists available for:

• The Patient Education Materials Assessment Tool (PEMAT) and User’s Guide The Patient Education Materials Assessment Tool (PEMAT) is a systematic method to evaluate and compare the understandability and actionability of patient education materials . It is designed as a guide to help determine whether patients will be able to understand and act on information. Separate tools are available for use with print and audiovisual materials.
• MMAT (Mixed Methods Appraisal Tool) 2018 "The MMAT is a critical appraisal tool that is designed for the appraisal stage of systematic mixed studies reviews, i.e., reviews that include qualitative, quantitative and mixed methods studies. It permits to appraise the methodological quality of five categories to studies: qualitative research, randomized controlled trials, non randomized studies, quantitative descriptive studies, and mixed methods studies."
• PEDro Scale (Physiotherapy Evidence Database) The PEDro scale was developed to help users rapidly identify trials that are likely to be internally valid and have sufficient statistical information to guide clinical decision-making.
• Risk of Bias (RoB) Tools The RoB 2 tool is designed for assessing risk of bias in randomized trials , while the ROBINS-I tool is meant for assessing non-randomized studies of interventions .
• CanChild / McMaster EBP Research Group - Evidence Review Forms Evidence review forms from the McMaster University Occupational Therapy Evidence-Based Practice for appraising quantitative and qualitative evidence.

Reporting Guidelines

• CONSORT (CONsolidated Standards Of Reporting Trials) The CONSORT Statement is an evidence-based, minimum set of standards for reporting of randomized trials . It offers a standard way for authors to prepare reports of trial findings, facilitating their complete and transparent reporting, and aiding their critical appraisal and interpretation.
• TREND (Transparent Reporting of Evaluations with Nonrandomized Designs) The TREND statement has a 22-item checklist specifically developed to guide standardized reporting of non-randomized controlled trials .

RISMA is an evidence-based minimum set of items for reporting in systematic reviews and meta-analyses . PRISMA primarily focuses on the reporting of reviews evaluating the effects of interventions, but can also be used as a basis for reporting systematic reviews with objectives other than evaluating interventions.

There are also extensions available for scoping reviews , as well as other aspects or types of systematic reviews.

• SQUIRE 2.0 (Standards for QUality Improvement Reporting Excellence) The SQUIRE guidelines provide a framework for reporting new knowledge about how to improve healthcare (i.e., quality improvement ). These guidelines are intended for reports that describe system level work to improve the quality, safety, and value of healthcare, and used methods to establish that observed outcomes were due to the intervention(s).

Searchable Registries of Appraisal Tools & Reporting Guidelines

• Equator Network: Enhancing the QUAlity and Transparency Of health Research Comprehensive searchable database of reporting guidelines for main study types and also links to other resources relevant to research reporting.
• The Registry of Methods and Tools for Evidence-Informed Decision Making The Registry of Methods and Tools for Evidence-Informed Decision Making ("the Registry") is a collection of resources to support evidence-informed decision making in practice, programs and policy. This curated, searchable resource offers a selection of methods and tools for each step in the evidence-informed decision-making process. Includes tools related to implementation science , assessing the applicability and transferability of evidence.

For a list of additional tools, as well as some commentary on their use, see:

Ma, L.-L., Wang, Y.-Y., Yang, Z.-H., Huang, D., Weng, H., & Zeng, X.-T. (2020). Methodological quality (risk of bias) assessment tools for primary and secondary medical studies: What are they and which is better ? Military Medical Research, 7 (1), 7. https://doi.org/10.1186/s40779-020-00238-8

Determining Level of Evidence

Determining the level of evidence for a particular study or information source depends on understanding, the nature of the research question that is being investigated and the  methodology  that was used to collect the evidence.  See these these resources for help understanding study methodologies .  

There are a number of evidence hierarchies that could be used to 'rank' evidence. Which hierarchy is applied often depends on disciplinary norms - students should refer to materials and guidance from their professors about which hierarchy is appropriate to use.

• Oxford Centre for Evidence Based Medicine - Levels of Evidence The CEBM has put together a suite of documents to enable ranking of evidence into levels. Where a study falls in the ranking depends on the methodology of the study, and what kind of question (e.g., therapy, prognosis, diagnosis) is being addressed.
• Joanna Briggs Levels of Evidence [PDF] The JBI Levels of Evidence and Grades of Recommendation are meant to be used alongside the supporting document (PDF) outlining their use.
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• Published: 31 January 2022

The fundamentals of critically appraising an article

• Sneha Chotaliya 1  

BDJ Student volume  29 ,  pages 12–13 ( 2022 ) Cite this article

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Sneha Chotaliya

We are often surrounded by an abundance of research and articles, but the quality and validity can vary massively. Not everything will be of a good quality - or even valid. An important part of reading a paper is first assessing the paper. This is a key skill for all healthcare professionals as anything we read can impact or influence our practice. It is also important to stay up to date with the latest research and findings.

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Chambers R, 'Clinical Effectiveness Made Easy', Oxford: Radcliffe Medical Press , 1998

Loney P L, Chambers L W, Bennett K J, Roberts J G and Stratford P W. Critical appraisal of the health research literature: prevalence or incidence of a health problem. Chronic Dis Can 1998; 19 : 170-176.

Brice R. CASP CHECKLISTS - CASP - Critical Appraisal Skills Programme . 2021. Available at: https://casp-uk.net/casp-tools-checklists/ (Accessed 22 July 2021).

White S, Halter M, Hassenkamp A and Mein G. 2021. Critical Appraisal Techniques for Healthcare Literature . St George's, University of London.

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Evidence Based Practice: Critical Appraisal

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What is a critical appraisal and why should you us it?

The critical appraisal of the quality of clinical research is one of the keys to informed decision-making in healthcare.  Critical appraisal is the process of carefully and systematically examining research evidence to judge its trustworthiness, its value and relevance in a particular context.

Critical appraisal skills promote understanding of:

• which treatments or interventions may really work;
• whether research has been conducted properly and has been reported reliably;
• which papers are clinically relevant;
• which services or treatments are potentially worth funding;
• whether the benefits of an intervention are likely to outweigh the harms or costs;
• what to believe when making decisions when there is conflicting research.

Critical appraisals are done using checklists, depending on the type of study being appraised. Common questions asked are:

• What is the research question?
• What is the study type (design)?
• What selection considerations were applied?
• What are the outcome factors and how are they measured?
• What are the study factors and how are they measured?
• What important potential confounders are considered?
• What is the statistical method used in the study?
• How were statistical results used and applied?
• What conclusions did the authors reach about the research question?
• Are ethical issues considered?

Information from Al-Jundi & Sakka, 2017; CASP, 2018 ; Mhaskar et al., 2009

Study Types

• General Information
• Cohort Study

Case-control study

• Cross-sectional study

Different types of clinical questions are answered by different types of study design.

Randomised Controlled Trial (RCT)

Used to answer questions about effects. Participants are randomised into two (or more) different groups and each group receives a different intervention. At the end of the trial, the effects of the different interventions are measured. Blinding (patients and investigators should not know which group the patient belongs to) is used to minimise bias. 

Non-Randomised Controlled Trial

This type of study does not apply randomisation or uses a method that does not meet randomisation standards, like eg. alternate assignment to groups, age-based groupings, etc. After the allocation of participants to groups, the Non-Randomised Controlled Trial resembles a Cohort Study.

( Grimes & Schulz, 2002 ; Public Health Action Support Team, 2017 ; Sut, 2014 )

Cohort study

Participants or subjects (not patients) with specific characteristics are identified as a 'cohort' (cohort=group) and followed over a long time (years or decades). Differences between them, such as exposure of possible risk factor(s), are measured. Used to answer questions about aetiology or prognosis. Cohort studies are a form of longitudinal study design that flows from the exposure to outcome. Prognostic cohort studies start with a group of patients with a specific condition and follow them up over time to see how the condition develops.

Looks at patients (cases) who already have a specific condition and match them with a control group who are very similar except they don't have the condition. Medical records and interviews are used to identify differences in exposure to risk factors in the two groups. Used to answer questions about aetiology, especially for rare conditions where a cohort study would not be feasible. 

Cross-sectional study/survey

A representative sample of a population is identified and examined or interviewed to establish whether or not a specific outcome is present. Used to answer questions about prevalence and diagnosis. For diagnostic studies, the sensitivity and specificity of a new diagnostic test is measured against a 'go ld standard' or reference test. Cross-sectional studies can be descriptive or analytical.

Critical Appraisal Tools

JBI Checklists

• Downs & Black

"Critical appraisal is the process of carefully and systematically examining research to judge its trustworthiness, and its value and relevance in a particular context."  ( Burls, 2009 )

Choosing an appraisal tool

Critical appraisal tools are designed to be used when reading and evaluating published research.

For best results, match the tool against the type of study you want to appraise. Some of the common critical appraisal tools are included here.

Critical Appraisal Skills Programme (CASP) checklists

CASP provides a number of checklists covering RCTs, cohort studies, systematic reviews and more.

Joanna Briggs Institute Critical Appraisal Tools have been developed by the JBI and collaborators and approved by the JBI Scientific Committee, following extensive peer review. JBI offers a large number of appraisal checklists for both experimental and observational studies. Word and PDF versions of each are available.

STROBE Statement checklists

The STROBE checklists are designed for the reporting of observational (cohort, case-control, and cross-sectional) studies and can be applied to the critical appraisal of these types of study. Includes individual and mixed study checklists.

Critical appraisal

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Critical Appraisal of Clinical Research

Azzam al-jundi.

1 Professor, Department of Orthodontics, King Saud bin Abdul Aziz University for Health Sciences-College of Dentistry, Riyadh, Kingdom of Saudi Arabia.

Salah Sakka

2 Associate Professor, Department of Oral and Maxillofacial Surgery, Al Farabi Dental College, Riyadh, KSA.

Evidence-based practice is the integration of individual clinical expertise with the best available external clinical evidence from systematic research and patient’s values and expectations into the decision making process for patient care. It is a fundamental skill to be able to identify and appraise the best available evidence in order to integrate it with your own clinical experience and patients values. The aim of this article is to provide a robust and simple process for assessing the credibility of articles and their value to your clinical practice.

Introduction

Decisions related to patient value and care is carefully made following an essential process of integration of the best existing evidence, clinical experience and patient preference. Critical appraisal is the course of action for watchfully and systematically examining research to assess its reliability, value and relevance in order to direct professionals in their vital clinical decision making [ 1 ].

Critical appraisal is essential to:

• Combat information overload;
• Identify papers that are clinically relevant;
• Continuing Professional Development (CPD).

Carrying out Critical Appraisal:

Assessing the research methods used in the study is a prime step in its critical appraisal. This is done using checklists which are specific to the study design.

Standard Common Questions:

• What is the research question?
• What is the study type (design)?
• Selection issues.
• What are the outcome factors and how are they measured?
• What are the study factors and how are they measured?
• What important potential confounders are considered?
• What is the statistical method used in the study?
• Statistical results.
• What conclusions did the authors reach about the research question?
• Are ethical issues considered?

The Critical Appraisal starts by double checking the following main sections:

I. Overview of the paper:

• The publishing journal and the year
• The article title: Does it state key trial objectives?
• The author (s) and their institution (s)

The presence of a peer review process in journal acceptance protocols also adds robustness to the assessment criteria for research papers and hence would indicate a reduced likelihood of publication of poor quality research. Other areas to consider may include authors’ declarations of interest and potential market bias. Attention should be paid to any declared funding or the issue of a research grant, in order to check for a conflict of interest [ 2 ].

II. ABSTRACT: Reading the abstract is a quick way of getting to know the article and its purpose, major procedures and methods, main findings, and conclusions.

• Aim of the study: It should be well and clearly written.
• Materials and Methods: The study design and type of groups, type of randomization process, sample size, gender, age, and procedure rendered to each group and measuring tool(s) should be evidently mentioned.
• Results: The measured variables with their statistical analysis and significance.
• Conclusion: It must clearly answer the question of interest.

III. Introduction/Background section:

An excellent introduction will thoroughly include references to earlier work related to the area under discussion and express the importance and limitations of what is previously acknowledged [ 2 ].

-Why this study is considered necessary? What is the purpose of this study? Was the purpose identified before the study or a chance result revealed as part of ‘data searching?’

-What has been already achieved and how does this study be at variance?

-Does the scientific approach outline the advantages along with possible drawbacks associated with the intervention or observations?

IV. Methods and Materials section : Full details on how the study was actually carried out should be mentioned. Precise information is given on the study design, the population, the sample size and the interventions presented. All measurements approaches should be clearly stated [ 3 ].

V. Results section : This section should clearly reveal what actually occur to the subjects. The results might contain raw data and explain the statistical analysis. These can be shown in related tables, diagrams and graphs.

VI. Discussion section : This section should include an absolute comparison of what is already identified in the topic of interest and the clinical relevance of what has been newly established. A discussion on a possible related limitations and necessitation for further studies should also be indicated.

Does it summarize the main findings of the study and relate them to any deficiencies in the study design or problems in the conduct of the study? (This is called intention to treat analysis).

• Does it address any source of potential bias?
• Are interpretations consistent with the results?
• How are null findings interpreted?
• Does it mention how do the findings of this study relate to previous work in the area?
• Can they be generalized (external validity)?
• Does it mention their clinical implications/applicability?
• What are the results/outcomes/findings applicable to and will they affect a clinical practice?
• Does the conclusion answer the study question?
• -Is the conclusion convincing?
• -Does the paper indicate ethics approval?
• -Can you identify potential ethical issues?
• -Do the results apply to the population in which you are interested?
• -Will you use the results of the study?

Once you have answered the preliminary and key questions and identified the research method used, you can incorporate specific questions related to each method into your appraisal process or checklist.

1-What is the research question?

For a study to gain value, it should address a significant problem within the healthcare and provide new or meaningful results. Useful structure for assessing the problem addressed in the article is the Problem Intervention Comparison Outcome (PICO) method [ 3 ].

P = Patient or problem: Patient/Problem/Population:

It involves identifying if the research has a focused question. What is the chief complaint?

E.g.,: Disease status, previous ailments, current medications etc.,

I = Intervention: Appropriately and clearly stated management strategy e.g.,: new diagnostic test, treatment, adjunctive therapy etc.,

C= Comparison: A suitable control or alternative

E.g.,: specific and limited to one alternative choice.

O= Outcomes: The desired results or patient related consequences have to be identified. e.g.,: eliminating symptoms, improving function, esthetics etc.,

The clinical question determines which study designs are appropriate. There are five broad categories of clinical questions, as shown in [ Table/Fig-1 ].

[Table/Fig-1]:

Categories of clinical questions and the related study designs.

2- What is the study type (design)?

The study design of the research is fundamental to the usefulness of the study.

In a clinical paper the methodology employed to generate the results is fully explained. In general, all questions about the related clinical query, the study design, the subjects and the correlated measures to reduce bias and confounding should be adequately and thoroughly explored and answered.

Participants/Sample Population:

Researchers identify the target population they are interested in. A sample population is therefore taken and results from this sample are then generalized to the target population.

The sample should be representative of the target population from which it came. Knowing the baseline characteristics of the sample population is important because this allows researchers to see how closely the subjects match their own patients [ 4 ].

Sample size calculation (Power calculation): A trial should be large enough to have a high chance of detecting a worthwhile effect if it exists. Statisticians can work out before the trial begins how large the sample size should be in order to have a good chance of detecting a true difference between the intervention and control groups [ 5 ].

• Is the sample defined? Human, Animals (type); what population does it represent?
• Does it mention eligibility criteria with reasons?
• Does it mention where and how the sample were recruited, selected and assessed?
• Does it mention where was the study carried out?
• Is the sample size justified? Rightly calculated? Is it adequate to detect statistical and clinical significant results?
• Does it mention a suitable study design/type?
• Is the study type appropriate to the research question?
• Is the study adequately controlled? Does it mention type of randomization process? Does it mention the presence of control group or explain lack of it?
• Are the samples similar at baseline? Is sample attrition mentioned?
• All studies report the number of participants/specimens at the start of a study, together with details of how many of them completed the study and reasons for incomplete follow up if there is any.
• Does it mention who was blinded? Are the assessors and participants blind to the interventions received?
• Is it mentioned how was the data analysed?
• Are any measurements taken likely to be valid?

Researchers use measuring techniques and instruments that have been shown to be valid and reliable.

Validity refers to the extent to which a test measures what it is supposed to measure.

(the extent to which the value obtained represents the object of interest.)

• -Soundness, effectiveness of the measuring instrument;
• -What does the test measure?
• -Does it measure, what it is supposed to be measured?
• -How well, how accurately does it measure?

Reliability: In research, the term reliability means “repeatability” or “consistency”

Reliability refers to how consistent a test is on repeated measurements. It is important especially if assessments are made on different occasions and or by different examiners. Studies should state the method for assessing the reliability of any measurements taken and what the intra –examiner reliability was [ 6 ].

3-Selection issues:

The following questions should be raised:

• - How were subjects chosen or recruited? If not random, are they representative of the population?
• - Types of Blinding (Masking) Single, Double, Triple?
• - Is there a control group? How was it chosen?
• - How are patients followed up? Who are the dropouts? Why and how many are there?
• - Are the independent (predictor) and dependent (outcome) variables in the study clearly identified, defined, and measured?
• - Is there a statement about sample size issues or statistical power (especially important in negative studies)?
• - If a multicenter study, what quality assurance measures were employed to obtain consistency across sites?
• - Are there selection biases?
• • In a case-control study, if exercise habits to be compared:
• - Are the controls appropriate?
• - Were records of cases and controls reviewed blindly?
• - How were possible selection biases controlled (Prevalence bias, Admission Rate bias, Volunteer bias, Recall bias, Lead Time bias, Detection bias, etc.,)?
• • Cross Sectional Studies:
• - Was the sample selected in an appropriate manner (random, convenience, etc.,)?
• - Were efforts made to ensure a good response rate or to minimize the occurrence of missing data?
• - Were reliability (reproducibility) and validity reported?
• • In an intervention study, how were subjects recruited and assigned to groups?
• • In a cohort study, how many reached final follow-up?
• - Are the subject’s representatives of the population to which the findings are applied?
• - Is there evidence of volunteer bias? Was there adequate follow-up time?
• - What was the drop-out rate?
• - Any shortcoming in the methodology can lead to results that do not reflect the truth. If clinical practice is changed on the basis of these results, patients could be harmed.

Researchers employ a variety of techniques to make the methodology more robust, such as matching, restriction, randomization, and blinding [ 7 ].

Bias is the term used to describe an error at any stage of the study that was not due to chance. Bias leads to results in which there are a systematic deviation from the truth. As bias cannot be measured, researchers need to rely on good research design to minimize bias [ 8 ]. To minimize any bias within a study the sample population should be representative of the population. It is also imperative to consider the sample size in the study and identify if the study is adequately powered to produce statistically significant results, i.e., p-values quoted are <0.05 [ 9 ].

4-What are the outcome factors and how are they measured?

• -Are all relevant outcomes assessed?
• -Is measurement error an important source of bias?

5-What are the study factors and how are they measured?

• -Are all the relevant study factors included in the study?
• -Have the factors been measured using appropriate tools?

Data Analysis and Results:

- Were the tests appropriate for the data?

- Are confidence intervals or p-values given?

• How strong is the association between intervention and outcome?
• How precise is the estimate of the risk?
• Does it clearly mention the main finding(s) and does the data support them?
• Does it mention the clinical significance of the result?
• Is adverse event or lack of it mentioned?
• Are all relevant outcomes assessed?
• Was the sample size adequate to detect a clinically/socially significant result?
• Are the results presented in a way to help in health policy decisions?
• Is there measurement error?
• Is measurement error an important source of bias?

Confounding Factors:

A confounder has a triangular relationship with both the exposure and the outcome. However, it is not on the causal pathway. It makes it appear as if there is a direct relationship between the exposure and the outcome or it might even mask an association that would otherwise have been present [ 9 ].

6- What important potential confounders are considered?

• -Are potential confounders examined and controlled for?
• -Is confounding an important source of bias?

7- What is the statistical method in the study?

• -Are the statistical methods described appropriate to compare participants for primary and secondary outcomes?
• -Are statistical methods specified insufficient detail (If I had access to the raw data, could I reproduce the analysis)?
• -Were the tests appropriate for the data?
• -Are confidence intervals or p-values given?
• -Are results presented as absolute risk reduction as well as relative risk reduction?

Interpretation of p-value:

The p-value refers to the probability that any particular outcome would have arisen by chance. A p-value of less than 1 in 20 (p<0.05) is statistically significant.

• When p-value is less than significance level, which is usually 0.05, we often reject the null hypothesis and the result is considered to be statistically significant. Conversely, when p-value is greater than 0.05, we conclude that the result is not statistically significant and the null hypothesis is accepted.

Confidence interval:

Multiple repetition of the same trial would not yield the exact same results every time. However, on average the results would be within a certain range. A 95% confidence interval means that there is a 95% chance that the true size of effect will lie within this range.

8- Statistical results:

• -Do statistical tests answer the research question?

Are statistical tests performed and comparisons made (data searching)?

Correct statistical analysis of results is crucial to the reliability of the conclusions drawn from the research paper. Depending on the study design and sample selection method employed, observational or inferential statistical analysis may be carried out on the results of the study.

It is important to identify if this is appropriate for the study [ 9 ].

• -Was the sample size adequate to detect a clinically/socially significant result?
• -Are the results presented in a way to help in health policy decisions?

Clinical significance:

Statistical significance as shown by p-value is not the same as clinical significance. Statistical significance judges whether treatment effects are explicable as chance findings, whereas clinical significance assesses whether treatment effects are worthwhile in real life. Small improvements that are statistically significant might not result in any meaningful improvement clinically. The following questions should always be on mind:

• -If the results are statistically significant, do they also have clinical significance?
• -If the results are not statistically significant, was the sample size sufficiently large to detect a meaningful difference or effect?

9- What conclusions did the authors reach about the study question?

Conclusions should ensure that recommendations stated are suitable for the results attained within the capacity of the study. The authors should also concentrate on the limitations in the study and their effects on the outcomes and the proposed suggestions for future studies [ 10 ].

• -Are the questions posed in the study adequately addressed?
• -Are the conclusions justified by the data?
• -Do the authors extrapolate beyond the data?
• -Are shortcomings of the study addressed and constructive suggestions given for future research?
• -Bibliography/References:

Do the citations follow one of the Council of Biological Editors’ (CBE) standard formats?

10- Are ethical issues considered?

If a study involves human subjects, human tissues, or animals, was approval from appropriate institutional or governmental entities obtained? [ 10 , 11 ].

Critical appraisal of RCTs: Factors to look for:

• Allocation (randomization, stratification, confounders).
• Follow up of participants (intention to treat).
• Data collection (bias).
• Sample size (power calculation).
• Presentation of results (clear, precise).
• Applicability to local population.

[ Table/Fig-2 ] summarizes the guidelines for Consolidated Standards of Reporting Trials CONSORT [ 12 ].

[Table/Fig-2]:

Summary of the CONSORT guidelines.

Critical appraisal of systematic reviews: provide an overview of all primary studies on a topic and try to obtain an overall picture of the results.

In a systematic review, all the primary studies identified are critically appraised and only the best ones are selected. A meta-analysis (i.e., a statistical analysis) of the results from selected studies may be included. Factors to look for:

• Literature search (did it include published and unpublished materials as well as non-English language studies? Was personal contact with experts sought?).
• Quality-control of studies included (type of study; scoring system used to rate studies; analysis performed by at least two experts).
• Homogeneity of studies.

[ Table/Fig-3 ] summarizes the guidelines for Preferred Reporting Items for Systematic reviews and Meta-Analyses PRISMA [ 13 ].

[Table/Fig-3]:

Summary of PRISMA guidelines.

Critical appraisal is a fundamental skill in modern practice for assessing the value of clinical researches and providing an indication of their relevance to the profession. It is a skills-set developed throughout a professional career that facilitates this and, through integration with clinical experience and patient preference, permits the practice of evidence based medicine and dentistry. By following a systematic approach, such evidence can be considered and applied to clinical practice.

Financial or other Competing Interests

Critical appraisal for medical and health sciences: 3. Checklists

• Introduction
• 1. What is critical appraisal?
• 2. How do I start?
• 3. Checklists
• 4. Further reading and resources

Using the checklists

• Where do I look?

"The process of assessing and interpreting evidence by systematically considering its validity , results and relevance ."

The checklists will help you consider these three areas as part of your critical appraisal. See the following tabs for an overview. 

There will be particular biases to look out for, depending on the study type.

For example, the checklists and guidance will help you to scrutinise: 

• Was the study design appropriate for the research question?
• How were participants selected? Has there been an attempt to minimise bias in this selection process?
• Were potential ethical issues addressed? 
• Was there any failure to account for subjects dropping out of the study?

• How was data collected and analysed?
• Are the results reliable?
• Are the results statistically significant?

The following e- resources, developed by the University of Nottingham, may be useful when appraising quantitative studies:

• Confidence intervals
• Numbers Needed to Treat (NNT)
• Relative Risk Reduction (RRR) and Absolute Risk Reduction (ARR)

Finally, the checklists will assist you in determining:

• Can you use the results in your situation?
• How applicable are they to your patient or research topic?
• Was the study well conducted?
• Are the results valid and reproducible?
• What do the studies tell us about the current state of science?

Where do I look for this information?

Most articles follow the IMRAD format; Introduction, Methods, Results and Discussion (Greenhalgh, 2014, p. 28), with an abstract at the beginning.

The table below shows where in the article you might look to answer your questions:

• How to read a paper: the basics of evidence-based medicine and healthcare Greenhalgh, Trisha

Checklists and tools

• AMSTAR checklist for systematic reviews
• Cardiff University critical appraisal checklists
• CEBM Critical appraisal worksheets
• Scottish Intercollegiate Guidelines Network checklists
• JBI Critical appraisal tools
• CASP checklists

Checklists for different study types

• Systematic Review
• Randomised Controlled Trial (RCT)
• Qualitative study
• Cohort study
• Case-control study
• Case report
• In vivo animal studies
• In vitro studies
• Grey literature

There are different checklists for different study types, as each are prone to different biases.

The following tabs will give you an overview of some of the different study types you will come across, the sort of questions you will need to consider with each, and the checklists you can use.

Not sure what type of study you're looking at? See the  Spotting the study design  guide from the Centre for Evidence-Based Medicine for more help.

What is a systematic review?

A review of a clearly formulated question that uses systematic and explicit methods to identify, select and critically appraise relevant research, and to collect and analyse data from the studies that are included in the review. Statistical methods (meta-analysis) may or may not be used to analyse and summarise the results of the included studies.

From Cochrane Glossary

Some questions to ask when critically appraising a systematic review:

• Do you think all the important, relevant studies were included?
• Did the review’s authors do enough to assess quality of the included studies?
• If the results of the review have been combined, was it reasonable to do so?

From: Critical Appraisal Skills Programme (2018). CASP Systematic Review Checklist. [online] Available at:  https://casp-uk.net/casp-tools-checklists/ . Accessed: 22/08/2018

Checklists you can use to critically appraise a systematic review:

What is a randomised controlled trial?

An experiment in which two or more interventions, possibly including a control intervention or no intervention, are compared by being randomly allocated to participants. In most trials on intervention is assigned to each individual but sometimes assignment is to defined groups of individuals (for example, in a household) or interventions are assigned within individuals (for example, in different orders or to different parts of the body).

Some questions to ask when critically appraising RCTs:

• Was the assignment of patients to treatments randomised?
• Were patients, health workers and study personnel ‘blind’ to treatment? i.e. could they tell who was in each group?
• Were all of the patients who entered the trial properly accounted for at its conclusion? 
• Were all participants analysed in the groups in which they were randomised, i.e. was a  Intention to treat analysis undertaken?

From: Critical Appraisal Skills Programme (2018).  CASP Randomised Controlled Trial Checklist . [online] Available at:  https://casp-uk.net/casp-tools-checklists/ . Accessed: 22/08/2018

Checklists you can use to critically appraise an RCT:

What is a qualitative study?

Qualitative research is designed to explore the human elements of a given topic, where specific methods are used to examine how individuals see and experience the world...Qualitative methods are best for addressing many of the  why  questions that researchers have in mind when they develop their projects. Where quantitative approaches are appropriate for examining  who  has engaged in a behavior or  what  has happened and while experiments can test particular interventions, these techniques are not designed to explain why certain behaviors occur. Qualitative approaches are typically used to explore new phenomena and to capture individuals’ thoughts, feelings, or interpretations of meaning and process.

From Given, L. (2008)  The SAGE Encyclopedia of Qualitative Research Methods . Sage: London.

Some  questions to ask  when critically appraising a  qualitative study:  

• What was the selection process and was it appropriate? 
• Were potential ethical issues addressed, such as the potential impact of the researcher on the participants? Has anything been done to limit the effects of this?
• Was the data analysis done using explicit, rigorous, and justified methods?

From: Critical Appraisal Skills Programme (2018).  CASP Qualitative Checklist . [online] Available at:  https://casp-uk.net/casp-tools-checklists/ . Accessed: 22/08/2018

Checklists you can use to critically appraise a qualitative study:

Watch the video for an example of how to critically appraise a qualitative study using the CASP checklist:

What is a cohort study?

An observational study in which a defined group of people (the cohort) is followed over time. The outcomes of people in subsets of this cohort are compared, to examine people who were exposed or not exposed (or exposed at different levels) to a particular intervention or other factor of interest. A prospective cohort study assembles participants and follows them into the future. A retrospective (or historical) cohort study identifies subjects from past records and follows them from the time of those records to the present. Because subjects are not allocated by the investigator to different interventions or other exposures, adjusted analysis is usually required to minimise the influence of other factors (confounders).

Some questions to ask when critically appraising a cohort study

• Have there been any attempts to limit selection bias or other types of bias?
• Have the authors identified any confounding factors?
• Are the results precise and reliable?

From: Critical Appraisal Skills Programme (2018).  CASP Cohort Study Checklist . [online] Available at:  https://casp-uk.net/casp-tools-checklists/ . Accessed: 22/08/2018

Checklists you can use to critically appraise a cohort study:

What is a case-control study?

A study that compares people with a specific disease or outcome of interest (cases) to people from the same population without that disease or outcome (controls), and which seeks to find associations between the outcome and prior exposure to particular risk factors. This design is particularly useful where the outcome is rare and past exposure can be reliably measured. Case-control studies are usually retrospective, but not always.

Some questions to ask  when critically appraising a case-control study:

• Was the recruitment process appropriate? Is there any evidence of selection bias?
• Have all confounding factors been accounted for?
• How precise is the estimate of the effect? Were confidence intervals given?
• Do you believe the results?

From Critical Appraisal Skills Programme (2018). CASP Case Control Study Checklist . [online] Available at: https://casp-uk.net/casp-tools-checklists/ . Accessed: 22/08/2018. 

Checklists you can use to critically appraise a case-control study:

What is a case report?

A study reporting observations on a single individual.

Some questions to ask  when critically appraising a case report:

• Is the researcher’s perspective clearly described and taken into account?
• Are the methods for collecting data clearly described?
• Are the methods for analysing the data likely to be valid and reliable?
• Are quality control measures used?
• Was the analysis repeated by more than one researcher to ensure reliability?
• Are the results credible, and if so, are they relevant for practice? Are the results easy to understand?
• Are the conclusions drawn justified by the results?
• Are the findings of the study transferable to other settings?

From:  Roever and Reis (2015), 'Critical Appraisal of a Case Report', Evidence Based Medicine and Practice  Vol. 1 (1) 

Checklists you can use to critically appraise a case report:

• CEBM critical appraisal of a case study

What are in vivo animal studies?

In vivo animal studies are experiments carried out using animals as models. These studies are usually pre-clinical, often bridging the gap between in vitro experiments (using cell or microorganisms) and research with human participants.

Arrive guidelines  provide suggested minimum reporting standards for in vivo experiments using animal models. You can use these to help you evaluate the quality and transparency of animal studies

Some questions to ask when critically appraising in vivo studies:

• Is the study/experimental design explained clearly?
• Was the sample size clearly stated, with information about how sample size was decided?
• Was randomisation used?
• Who was aware of group allocation at each stage of the experiment?
• Were outcomes measures clearly defined and assessed?
• Were the statistical methods used clearly explained?
• Were all relevant details about animals used in the experiment clearly outlined (species, strain and substrain, sex, age or developmental stage, and, if relevant, weight)
• Were experimental procedures explained in enough detail for them to be replicated?
• Were the results clear, with relevant statistics included?

Adapted from:  The ARRIVE guidelines 2.0: author checklist

The ARRIVE guidelines 2.0: author checklist

While this checklist has been designed for authors to help while writing their studies, you can use the checklist to help you identify whether or not a study reports all of the required elements effectively.

SciRAP : evaluation of in vivo toxicity studies tool

The SciRAP method for evaluating reliability of  in vivo  toxicity studies consists of criteria for for evaluating both the   reporting quality  and  methodological quality  of studies, separately. You can switch between evaluation of reporting and methodological quality.

Further guidance 

Hooijmans CR, Rovers MM, de Vries RB, Leenaars M, Ritskes-Hoitinga M, Langendam MW. SYRCLE's risk of bias tool for animal studies. BMC Med Res Methodol. 2014 Mar 26;14:43. doi: 10.1186/1471-2288-14-43. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4230647/

Kilkenny C, et al, Improving bioscience research reporting: the ARRIVE guidelines for reporting animal research. PLoSBiol2010;8:e1000412. doi:10.1371/journal.pbio.100041220613859: https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.1000412

Moermond CT, Kase R, Korkaric M, Ågerstrand M. CRED: Criteria for reporting and evaluating ecotoxicity data. Environ Toxicol Chem. 2016 May;35(5):1297-309. doi: 10.1002/etc.3259.

What are in vitro studies?

In vitro studies involve tests carried out outside of a living organism, usually involving tissues, organs or cells.

Some questions to ask when critically appraising in vitro studies:

• Is there a clear and detailed description of the results, the test conditions and the interpretation of the results? 
• Do the authors clearly communicate the limitations of the method/s used?
• Do the authors use a validated method? 

Adapted from:  https://echa.europa.eu/support/registration/how-to-avoid-unnecessary-testing-on-animals/in-vitro-methods 

Guidance and checklists

SciRAP : evaluation of in vitro toxicity studies tool

The SciRAP method for evaluating reliability of  in vitro  toxicity studies consists of criteria for for evaluating both the   reporting quality  and  methodological quality  of studies, separately. You can switch between evaluation of reporting and methodological quality.

Development and validation of a risk-of-bias tool for assessing in vitro studies conducted in dentistry: The QUIN

Checklist designed to support the evaluation of in vitro dentistry studies, although can be used to assess risk of bias in other types of in vitro studies.

What is grey literature?

The term grey literature is used to describe a wide range of different information that is produced outside of traditional publishing and distribution channels, and which is often not well represented in indexing databases.

A widely accepted definition in the scholarly community for grey literature is

"information produced on all levels of government, academia, business and industry in electronic and print formats not controlled by commercial publishing" ie. where publishing is not the primary activity of the producing body." 

From: Third International Conference on Grey Literature in 1997 (ICGL Luxembourg definition, 1997  - Expanded in New York, 2004).

You can find out more about grey literature and how to track it down here.

Some questions to ask when critically appraising grey literature:

• Who is the author? Are they credible and do they have appropriate qualifications to speak to the subject?
• Does the source have a clearly stated aim or brief, and does it meet this?
• Does the source reference credible and authoritative sources?
• Is any data collection valid and appropriate for it's purpose?
• Are any limits stated? e.g. missing data, information outside of scope or resource of project.
• Is the source objective, or does the source support a viewpoint that could be biased?
• Does the source have a identifiable date?
• Is the source appropriate and relevant to the research area you have chosen?

Adapted from AACOS checklist

AACODS Checklist

The AACODS checklist has been designed to support the evaluation and critical appraisal of grey literature. 

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How to Write Critical Reviews

When you are asked to write a critical review of a book or article, you will need to identify, summarize, and evaluate the ideas and information the author has presented. In other words, you will be examining another person’s thoughts on a topic from your point of view.

Your stand must go beyond your “gut reaction” to the work and be based on your knowledge (readings, lecture, experience) of the topic as well as on factors such as criteria stated in your assignment or discussed by you and your instructor.

Make your stand clear at the beginning of your review, in your evaluations of specific parts, and in your concluding commentary.

Remember that your goal should be to make a few key points about the book or article, not to discuss everything the author writes.

Understanding the Assignment

To write a good critical review, you will have to engage in the mental processes of analyzing (taking apart) the work–deciding what its major components are and determining how these parts (i.e., paragraphs, sections, or chapters) contribute to the work as a whole.

Analyzing the work will help you focus on how and why the author makes certain points and prevent you from merely summarizing what the author says. Assuming the role of an analytical reader will also help you to determine whether or not the author fulfills the stated purpose of the book or article and enhances your understanding or knowledge of a particular topic.

Be sure to read your assignment thoroughly before you read the article or book. Your instructor may have included specific guidelines for you to follow. Keeping these guidelines in mind as you read the article or book can really help you write your paper!

Also, note where the work connects with what you’ve studied in the course. You can make the most efficient use of your reading and notetaking time if you are an active reader; that is, keep relevant questions in mind and jot down page numbers as well as your responses to ideas that appear to be significant as you read.

Please note: The length of your introduction and overview, the number of points you choose to review, and the length of your conclusion should be proportionate to the page limit stated in your assignment and should reflect the complexity of the material being reviewed as well as the expectations of your reader.

Write the introduction

Below are a few guidelines to help you write the introduction to your critical review.

Introduce your review appropriately

Begin your review with an introduction appropriate to your assignment.

If your assignment asks you to review only one book and not to use outside sources, your introduction will focus on identifying the author, the title, the main topic or issue presented in the book, and the author’s purpose in writing the book.

If your assignment asks you to review the book as it relates to issues or themes discussed in the course, or to review two or more books on the same topic, your introduction must also encompass those expectations.

Explain relationships

For example, before you can review two books on a topic, you must explain to your reader in your introduction how they are related to one another.

Within this shared context (or under this “umbrella”) you can then review comparable aspects of both books, pointing out where the authors agree and differ.

In other words, the more complicated your assignment is, the more your introduction must accomplish.

Finally, the introduction to a book review is always the place for you to establish your position as the reviewer (your thesis about the author’s thesis).

As you write, consider the following questions:

• Is the book a memoir, a treatise, a collection of facts, an extended argument, etc.? Is the article a documentary, a write-up of primary research, a position paper, etc.?
• Who is the author? What does the preface or foreword tell you about the author’s purpose, background, and credentials? What is the author’s approach to the topic (as a journalist? a historian? a researcher?)?
• What is the main topic or problem addressed? How does the work relate to a discipline, to a profession, to a particular audience, or to other works on the topic?
• What is your critical evaluation of the work (your thesis)? Why have you taken that position? What criteria are you basing your position on?

Provide an overview

In your introduction, you will also want to provide an overview. An overview supplies your reader with certain general information not appropriate for including in the introduction but necessary to understanding the body of the review.

Generally, an overview describes your book’s division into chapters, sections, or points of discussion. An overview may also include background information about the topic, about your stand, or about the criteria you will use for evaluation.

The overview and the introduction work together to provide a comprehensive beginning for (a “springboard” into) your review.

• What are the author’s basic premises? What issues are raised, or what themes emerge? What situation (i.e., racism on college campuses) provides a basis for the author’s assertions?
• How informed is my reader? What background information is relevant to the entire book and should be placed here rather than in a body paragraph?

Write the body

The body is the center of your paper, where you draw out your main arguments. Below are some guidelines to help you write it.

Organize using a logical plan

Organize the body of your review according to a logical plan. Here are two options:

• First, summarize, in a series of paragraphs, those major points from the book that you plan to discuss; incorporating each major point into a topic sentence for a paragraph is an effective organizational strategy. Second, discuss and evaluate these points in a following group of paragraphs. (There are two dangers lurking in this pattern–you may allot too many paragraphs to summary and too few to evaluation, or you may re-summarize too many points from the book in your evaluation section.)
• Alternatively, you can summarize and evaluate the major points you have chosen from the book in a point-by-point schema. That means you will discuss and evaluate point one within the same paragraph (or in several if the point is significant and warrants extended discussion) before you summarize and evaluate point two, point three, etc., moving in a logical sequence from point to point to point. Here again, it is effective to use the topic sentence of each paragraph to identify the point from the book that you plan to summarize or evaluate.

Questions to keep in mind as you write

With either organizational pattern, consider the following questions:

• What are the author’s most important points? How do these relate to one another? (Make relationships clear by using transitions: “In contrast,” an equally strong argument,” “moreover,” “a final conclusion,” etc.).
• What types of evidence or information does the author present to support his or her points? Is this evidence convincing, controversial, factual, one-sided, etc.? (Consider the use of primary historical material, case studies, narratives, recent scientific findings, statistics.)
• Where does the author do a good job of conveying factual material as well as personal perspective? Where does the author fail to do so? If solutions to a problem are offered, are they believable, misguided, or promising?
• Which parts of the work (particular arguments, descriptions, chapters, etc.) are most effective and which parts are least effective? Why?
• Where (if at all) does the author convey personal prejudice, support illogical relationships, or present evidence out of its appropriate context?

Keep your opinions distinct and cite your sources

Remember, as you discuss the author’s major points, be sure to distinguish consistently between the author’s opinions and your own.

Keep the summary portions of your discussion concise, remembering that your task as a reviewer is to re-see the author’s work, not to re-tell it.

And, importantly, if you refer to ideas from other books and articles or from lecture and course materials, always document your sources, or else you might wander into the realm of plagiarism.

Include only that material which has relevance for your review and use direct quotations sparingly. The Writing Center has other handouts to help you paraphrase text and introduce quotations.

Write the conclusion

You will want to use the conclusion to state your overall critical evaluation.

You have already discussed the major points the author makes, examined how the author supports arguments, and evaluated the quality or effectiveness of specific aspects of the book or article.

Now you must make an evaluation of the work as a whole, determining such things as whether or not the author achieves the stated or implied purpose and if the work makes a significant contribution to an existing body of knowledge.

Consider the following questions:

• Is the work appropriately subjective or objective according to the author’s purpose?
• How well does the work maintain its stated or implied focus? Does the author present extraneous material? Does the author exclude or ignore relevant information?
• How well has the author achieved the overall purpose of the book or article? What contribution does the work make to an existing body of knowledge or to a specific group of readers? Can you justify the use of this work in a particular course?
• What is the most important final comment you wish to make about the book or article? Do you have any suggestions for the direction of future research in the area? What has reading this work done for you or demonstrated to you?

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The Critical Appraisal of the Article

Introduction, critical appraisal, relevance of the study, validity of the study, results of the study, strengths and limitations of the study, recommendations, reference list.

Critical appraisal is an important factor to determine the relevance, validity, and transparency of the research. This paper presents the critical appraisal of the article ‘Light drinking in pregnancy, a risk for behavioral problems and cognitive deficits at 3 years of age’ with special focus on the relevance of this article, validity of the article, and validity of the result of the research in the article.

It is a critical appraisal of the article ‘Light drinking in pregnancy, a risk for behavioral problems and cognitive deficits at 3 years of age’ which was published by Oxford University Press on behalf of the International Epidemiological Association. “Critical appraisal is the process of systematically examining research evidence to assess its validity, relevance and results before using it to inform a decision.” (Abdel-Ghaffar, n.d., p.12). Critical appraisal is an important part of the evidence-based clinical practice to assess the validity of the research before going to implement the results of the study.

Researches have shown that heavy drinking during pregnancy affects children in their cognitive and behavioral development. But, there prevails ignorance on whether light drinking of the pregnant lady will affect the fetus. The objective of the study is to assess whether there is any behavioral problem and cognitive deficits among the children of those who drink lightly during pregnancy. It is a relevant subject for the time being. There are strong debates throughout the world that emphasizes the side effects of using alcohol by pregnant ladies. The result of the study shows that children born to mothers who drink lightly during pregnancy do not inflict the problem of behavioral disorders and cognitive deficits. But, the research reveals that children of heavy drinking mothers during pregnancy expose to different health issues. The result of the study can be taken for public information since there lacks of knowledge on the problem.

This study used the Millennium Cohort study which is a longitudinal study of infants who are born in the United Kingdom and the sample was taken from England, Wales, Scotland, and Northern Island. Interviews and home visits were the two methods used in the assessment. Three questionnaires were used, namely, Strengths and Difficulties Questionnaire (SDQ) to assess the behavioral problems and British Ability Scale (BAS) and the Bracken School Readiness Assessment (BSRA) to assess the cognitive deficits of the children. The questions in the interview focused on the socio-economic situation, health problems, and drinking during pregnancy. The study addressed the real problem and achieved its objectives. Interviews were conducted by experts. There were two steps in the study and the first part of the survey was conducted when the cohort members were aged 9 months and the second part of the survey was conducted when they became three years. Therefore, they completed the follow-up accurately.

The findings answer the research objective that drinking lightly during pregnancy will not lead to the behavioral problems and cognitive deficits of the children. The result is very significant and precise to the objective of the study. It was noticeable that the J-shaped relationship between drinking during pregnancy and scores obtained by the children. There were no variations between the results of abstinent mothers and light drinkers at the time of pregnancy.

In this study, two-third of the mothers were those who include in the category of abstinence, twenty-nine percent were light drinkers, six percent were moderate drinkers and two percent were heavy drinkers.

“The data used in our study were from a large nationally representative sample of young children that were collected prospectively. However, the Millennium Cohort Study sample is not representative of all pregnancies or births and so data on miscarriages, stillbirths, and neonatal deaths were not included.” (Kelly, Y., Sacker, Gray, Kelly, J., Wolke & Quigley, 2008, p.6). This study unravels the widespread alcohol consumption of pregnant women even though there is a social stigma. The main drawbacks in the study are when there is a stigma about the consumption of alcohol, people will be reluctant to be open about and it is very difficult to give correct measurements for the light drinkers. It cannot be defined accurately what amount is regarded as a light drink, and therefore, it may be hard to restrict the problem to a questionnaire. There may be some other causes for the behavioral problem of children other than the consumption of alcohol. Therefore, the factors like genetic make-up, social determinants such as financial condition; family background, etc also should be taken into consideration and should be assessed very systematically and scientifically.

Pregnant women may probably be loathed to reveal about the intake of alcohol since there exists stigma in society. Therefore the use of a questionnaire would be inappropriate to scribe the responses of the clients. There is vagueness in many of the terms used in the study. Some concepts are beyond the actual definition. For example, light drinking cannot be defined objectively and it varies from person to person. Social drinkers can be categorized as light drinkers but the question is up to what level and quantity. Therefore the responses of the client cannot be limited to some of the questions paused in the questionnaire. To get accurate data for the study and to get the pulse of the clients, it is better to use in-depth interviews and observant participation methods. The quantitative nature of the study may hamper accurate results and thereby reliability. The next flaw of this study is that it had two sweeps. The first had conducted when the children were at nine years of old and the second sweep was conducted when the children were at three years of old. These two sweeps of the study cannot bring effective and reliable information on how the slight drinking of mothers affects the children since there are other leading factors to the development of cognitive and behavioral defects. If the study is conducted using the interview method, the researcher can include the questions according to the changing perceptions of the social norms. When the social norms are being changed in time, the questionnaire which is developed years back will not be apt at the time of the study. Therefore what I would suggest is that it could have been made better and the result could have more been reliable if the study had been conducted qualitatively.

The consumption of alcohol by pregnant women is considered a risk factor for the physical, mental, and cognitive growth of children. Public people have not received accurate information on this issue. The above-referred article shows the outcome of the research on whether the light drinking habit of the mother hampers the development of the fetus in her womb. This paper substantiates the fact that slight drinking of pregnant women will not affect the cognitive and behavioral disorders of the children. The study is needed of the time and it is valid to provide current information on the problem. At the same time, it has underestimated the result of the study being used by questionnaire and quantitative study.

Abdel-Ghaffar, S. (n.d.). Critical appraisal: An overview: What is critical appraisal?. Faculty of Medicine, Cairo University. Web.

Kelly, Y., Sacker, A., Gray, R., Kelly, J., Wolke, D., & Quigley, M A. (2008). Light drinking in pregnancy, a risk for behavioral problems and cognitive deficits at 3 years of age: Strengths and limitations of the study. International Journal of Epidemiology , 1-12. Oxford University Press.

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Nursing Assignment: Critical Appraisal Essay

Added on   2020-05-28

About This Document

This is a  Critical appraisal assignment example for nursing. This assignment can also be called a critical appraisal example essay, Critical appraisal essay example, Critical appraisal essay, Example of critical appraisal essay, Critical appraisal example, and Example of a critical appraisal essay, etc.  

   Added on  2020-05-28

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