critical appraisal of published article

Critical Appraisal

Critical Appraisal of Published ArticleDr. Yogesh K Singhal 2nd Year PG student Department of Community medicine RNT Medical CollegeUdaipur (Raj.)Dr YKS 20151

Dr Samira alsenany

Purpose of this seminar The purpose of this seminar is to provide a brief overview of the critical appraisal process.

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

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Critical AppraisalA critical review must identify the strengths and limitations in a research paper and this should be carried out in a systematic manner.

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Critical AppraisalTo practice medicine we need evidence. Of course Critical appraisal of an article will give evidence. The Critical Appraisal helps in developing the necessary skills to make sense of scientific evidence, based on validity, results and relevance.Dr YKS 20155

Critical Appraisal Putting research into practice Critical appraisal is an essential step in the process of putting research into practice.

Asking questions about research methodology, Scrutinizing data collection & statistical methods, Evaluating the findings and results will help to determine whether that articles conclusions should influence practical decision-making.Dr YKS 20156

Journal ClubsAre organized for critical evaluation of research articles.Dr YKS 20157

Critical Appraisal for a clinicianIs essential to advance the knowledge constantly for clinical practice.Dr YKS 20158

Critical Appraisal for a public health personto keep updated regarding the contemporary practices in health care administration, therapies, equipment, diagnostics and the financial implications.Dr YKS 20159

When should Critically Appraise? Conducting literature reviews for grant proposals.

Evaluating the effectiveness, costs, and benefits of health programs.

Establishing new health programs.

Implementing policies; and Public health decision making, especially at the senior management level.Dr YKS 201510

Why Critical Appraisal is essential?Many of the research are not in good quality and many studies are biased and their results are untrue. This can lead us to draw false conclusions.If, these false conclusions are applied to population, may leads to a public health problem.

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Why do we need to critically appraise ?Article was published in a scientific journal so it must be correct (its a myth)Many journals get payment from author for publishing their articles.Dr YKS 2015Common misconception about research articles

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Why do we need to critically appraise ?It usually comes as a surprise to students to learn that some published articles belongs in the bin and should not be used to inform practice (Trisha Greenhalgh, 2006)Dr YKS 201513

How Critically Appraise a published articleDr YKS 2015

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Step 1 : To Decide the Article to appraiseConduct a literature search and obtain full text articles.

Look at the title : Is it interesting ?; Likely to be useful in your practice? Yes/No.Dr YKS 2015

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Examples of few topics A trust-based consumer decision making model in electronic commerce : role of trust, perceived risk, and their antecedents

Particle motion and the theory of charcoal analysis: source area, transport, deposition, and sampling

Long Term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals with Type 2 Diabetes: Four Year Results of the Look AHEAD Trial

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Examples of few topics A trust-based consumer decision making model in electronic commerce : role of trust, perceived risk, and their antecedents

Particle motion and the theory of charcoal analysis: source area, transport, deposition, and sampling

Long Term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals with Type 2 Diabetes: Four Year Results of the Look AHEAD Trial

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Select the TopicLong Term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals with Type 2 Diabetes: Four Year Results of the Look AHEAD Trial

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START READING

First know about Contents of a research article18

Anatomy of a Scientific ArticleAbstractIntroductionMaterials and MethodsResultsDiscussionConclusion/ RecommendationDr YKS 201519

Critically Appraise What You Read.

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And Keep giving your comments on a separate paper20

Step 2: AbstractUse the information found in the abstract to answer the questions below:

Likely to be useful in your practice?Are your issues discussed there?What are the main findings of the research?Do you want to know more after reading the abstract?Was the research done in a similar setting to yours?

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Abstract - after reading

You may conclude that the study is not reliable merely by reading the abstract.

in such case, move on to another article!

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Abstract after reading

You may conclude that the study is reliable merely by reading the abstract.

go ahead and start reading the article

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OUR ARTICLE FOR APPRAISAL Long Term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals with Type 2 Diabetes: Four Year Results of the Look AHEAD TrialDr YKS 2015

Abstract

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Step 3 : IntroductionThe introduction will help to identify the key concepts, goals, subjects, and themes of the research.

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Introduction : Questions to AskWhy was it done? clear statement of the purpose of the study.

Does the research question has some element of novelty (is likely to add to existing knowledge rather than reconfirming the already well established facts).Dr YKS 201527

Introduction : Questions to Ask

The absence of such statements can imply that the authors had no clear idea of what they were trying to find out.Or they didnt find anything but wanted to publish!

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Long Term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals with Type 2 Diabetes: Four Year Results of the Look AHEAD Trial - INTRODUCTION29

Step 4 : Material & MethodologyThe Methodology will give a step-by-step description of exactly how the study was carried out.Brief but should include enough detail to enable one to judge quality.Type of studyMention of study populationCalculation of the sample sizemethod of samplingidentified all the potential confounding factors (PCFs)Description of QuestionnairePhysical instruments and techniques usedBiases, if anyDr YKS 201530

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Methods : TYPES OF STUDIES

Dr YKS 2015Different research questions require different study designs.

the best design for studies evaluating the effectiveness of an intervention or treatment is a Randomized controlled trial.

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Error in study analysis ????Dr YKS 2015In a cohort study odds ratio was calculated ??? 32

ConfoundersConfounders are minimizing by taking action

during designing (Randomisation/ Restriction/ Matching)OR

during analysis (Standardisation / Stratified analysis/ Mathematical modelling)Dr YKS 201533

Biases Dr YKS 2015

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Is the sample large enough to produce significant results?Has the data been presented in a simple, intelligible form?Are the statistical methods appropriate?

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Methodology : Statistical Analysis35

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Methodology: Questions to Ask Where the study was done? who was studied and how they were recruited.Is it primary or secondary data How the data was collected (interviews, focus groups, questionnaires, surveys, observations, etc.).Basic demographics must be there.

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Dr YKS 2015Long Term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals with Type 2 Diabetes: Four Year Results of the Look AHEAD Trial METHODOLOGY 1 page

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Limitation of studyThe study excluded patients younger than 45 years and older than 76 years old. In fact, 45% of pre-screened participants (n=26522) were excluded and the major reason for exclusion was age (13.5%) Dr YKS 201539


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Limitation of studyOnly participants who could successfully complete a maximal graded exercise test at screening were included.maximal graded exercise test is not definedDr YKS 201541

Dr YKS 2015Long Term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals with Type 2 Diabetes: Four Year Results of the Look AHEAD Trial - METHODOLOGY 1 page

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Limitation of studyParticipants were provided with meal replacements free of charge which may be too costly to replicate in a primary care setting.Patients in the ILI group received free partial meal replacement which, if missed, may take away from the motivation of patients to rightly follow dietary recommendations.It is uncertain how the absence of free meal replacements in primary care settings may lead to different results from the study findings.

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Dr YKS 2015Long Term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals with Type 2 Diabetes: Four Year Results of the Look AHEAD Trial METHODOLOGY - 1 page

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Limitation of studyPhysical activity (brisk walking) was not scientifically defined so that its interpretation can be subjective and difficult to determine.Activities similar to intensity of brisk walking who will monitor in a self-monitored subject

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Dr YKS 2015Long Term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals with Type 2 Diabetes: Four Year Results of the Look AHEAD Trial - METHODOLOGY - 1

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Limitation of studySubjects are self monitored and use of self-reported data cant be considered authentic.Dr YKS 201547


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Limitation of studyFor all the DSE participants in the Look AHEAD trial, were seen yearly while ILI participants were seen more frequently.

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Limitation of studyFor all the participants in the Look AHEAD trial, assessment of weight and many other outcomes were conducted yearly after baseline measurements. The interval between measurements may be long and potentially important variability in outcome trends could be missed. Dr YKS 201553


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Step 5 : Results The aims in the introduction should be addressed in the results.Maintain the logical sequences (no bland statements)All research has some flaws , the impact of the flaws need to assessed.

Dr YKS 2015If the findings are statistically significant, are they also of clinical/public health relevance?If the findings are statistically non significant is it possible that a real effect may have been missed due to low study power as consequence of low sample size.

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Dr Samira alsenany

Results : Questions to AskA- Are the results of the study valid?B-What are the results?C-Will the results help locally?Are the conclusions drawn by the authors based on the actual findings of the study?Do you think the study results can be gainfully utilized in your own clinical / preventive / public health practice?

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Dr Samira alsenany

Dr YKS 2015Long Term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals with Type 2 Diabetes: Four Year Results of the Look AHEAD Trial - RESULTS 1 page

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Dr YKS 2015Long Term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals with Type 2 Diabetes: Four Year Results of the Look AHEAD Trial - RESULTS 1 page

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Strengths & Limitation of studyLarge sample size (n=5145) provided sufficient power to detect clinically relevant differences between effects of study arms. Excellent retention rate - Look AHEAD trial reported that 94.1% of participants in the intervention arm (ILI) and 93.1% in the comparator arm (DSE) completed the 4-year assessment.

The Look AHEAD study does not provide information about how missing data (dropouts/leftouts) were handled.

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Step 6 : Discussion & ConclusionHow well are the results related to other research on the same topic?In the discussion or conclusions section, is there a review of how these results compare or contrast with prior research? If this report found something different from previous research, then its important to question on appraising the reliability of the findings.The limitations of the research and possible implications which are not mentioned in the abstract.

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Discussion : Questions to askCompare the raw data given in the tables with the results analyzed in the discussion and conclusions Are the results reported in the conclusions consistent with what is reported in the tables? Is the interpretation consistent with what the actual findings were? Dr YKS 2015

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Dr YKS 2015Long Term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals with Type 2 Diabetes: Four Year Results of the Look AHEAD Trial Discussion & Conclusion

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Long Term Effects of a Lifestyle Intervention on Weight and Cardiovascular Risk Factors in Individuals with Type 2 Diabetes: Four Year Results of the Look AHEAD Trial Discussion & Conclusion

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Strengths of studyThe study has a longer duration than many others and provides a more comprehensive long-term assessment of behavioural intervention on weight loss and associated health benefits.

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Overall Strengths & Limitation of studyDr YKS 2015StrengthsLimitation1. Large sample size (n=5145) provided sufficient power to detect clinically relevant differences between effects of study arms. 2. The study has a longer duration than many others and provides a more comprehensive long-term assessment of behavioural intervention on weight loss and associated health benefits. 3. Over 93% of participants were assessed at each year for the four years making it possible to evaluate more comprehensively the durability of measured outcomes and the long-term effects of the intervention. 1. The study excluded patients younger than 45 years and older than 76 years old. In fact, 45% of pre-screened participants (n=26522) were excluded because of age factor.2. Only participants who could successfully complete a maximal graded exercise test at screening were included 3. Patients in the ILI group received free partial meal replacement which may not be offered in a primary care setting and may take away from the motivation of patients to rightly follow dietary recommendations.

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Thanks

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Critical Appraisal of my presentation66

critical appraisal of published article

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