EBM: Critical Appraisal of an Article on Therapy

EBM: Critical Appraisal of an Article on Systematic ReviewSudan Evidence-Based Medicine Association TemplateDeveloped by: Dr. Imad Salah Ahmed Hassan MD (UK) FACP FRCPI MAcadMEd MSc (UK) MBBS (U of K)

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Clinical Scenario

Formulate a Well-Built Clinical QuestionPatientInterventionComparisonOutcome

Outline your Search Strategy:Search Terms/Keywords/Mesh termsSearch site/Search EnginePubmed via PICOPubmed Search Box & LimitsPubmed Clinical QueriesPubmed Advanced SearchCochrane LibraryOther

Outline Current PracticeTip: From the Introduction Section or from a Guideline

Select a Reasonable Piece of Research

Tip:Paste the title, authors, journal details hereType of Study: Systematic ReviewDate published:Number of Pages:Quality of journal i.e. impact factor (get from Google!)Linked-In: Author Details/Picture

Reason(s) for Selecting this Piece of ResearchTip: Common ReasonsAnswers my QUESTIONFree articleRecent ArticleReputable Journal Other

Summarize the Results of your ArticleTip: Paste the Conclusion from the Abstract here

Apply Your Appraisal SchemeTip: Use the RVRA Scheme: Based on the National & Gulf Center for Evidence-based Health PracticeRelevanceValidityResultsApplicability

Apply Your Appraisal SchemeTip: Use the RVRA SchemeRelevancePersonal KnowledgeValidityMethods SectionResultsResults SectionApplicabilityPersonal Interpretation/Experience

Apply Your Appraisal SchemeRelevanceDoes the study address a common problem in your practice? Does the study address an important outcome to you or to your patient? (DOE vs. POEM) Assuming that the study conclusion is true; would it lead to a change in your practice?

Apply Your Appraisal SchemeValidityDid the overview address a focused clinical question?

Patients? Exposures? Outcomes? Therapy? Causation? Diagnosis? Prognosis?

Apply Your Appraisal SchemeValidity Were the criteria used to select articles for inclusion appropriate? Tip: From Method Section or Copy the Method Summary from the Abstract.Copy the Inclusion & Exclusion CriteriaCopy the Study Flow Chart to your PresentationCopy the Inclusion & Exclusion Criteria

Apply Your Appraisal SchemeValidity Is it unlikely that important, relevant studies were missed?

1-Bibliographic databases? 2-Reference lists? 3-Personal contacts? 4. No language Restrictions? Was the validity of the included studies appraised?1-Validity criteria? 2-Risk of Bias

Apply Your Appraisal SchemeValidity Were assessments of studies reproducible? 1-Blinded reviewers? 2-Inter-observer agreement? Were the results similar from study to study? Tests of heterogeneity? The I2Test.Is there any Publication Bias: Include a Funnel Plot

Apply Your Appraisal SchemeResults clinical significance (in MP : Magnitude & Precision) What are the overall results of the review? 1- Overall ORs, RRs 2- Or WMDTip: Copy the Forest PlotPrecision of the effect: How precise were the results? Confidence intervals? Narrow or Wide

Summarize the Study BiasesSelection, Attrition, Performance, Detection Biases, Conflict of Interest etc.

Summarize the Study StrengthTip: From the Discussion or Letter to the Editor/Editorial Comment etc.E.G.: Number of Patients, Randomization Method, Least Biases, Statistical Tests used, Outcome Measures, Ascertainment, Drop-outs, Length of Follow-up etc.

Summarize the Study WeaknessesTip: From the Discussion or Letter to the Editor/Editorial Comment etc.E.G.: Number of Patients, Randomization Method, Least Biases, Statistical Tests used, Outcome Measures, Ascertainment, Drop-outs, Length of Follow-up etc.

Summarize the StudyTip: From the Discussion or Letter to the Editor/Editorial Comment etc.

Unanswered Questions from the StudyTip: From the Discussion or Letter to the Editor/Editorial Comment etc.

Apply Your Appraisal SchemeApplicability I (in IPPP: Intervention Population - Preferences-Potential Benefits - Harm Can the results be applied to my patient care? Can you do the Intervention exactly as it is described in the paper Is your Patient similar to the population of the study? Did you examine your patients Preferences? Are the potential benefits outweigh the potential harms & cost, to my patient? Were all clinically important outcomes considered? Any substitute surrogate or intermediate endpoints? NNT for different outcomes?

Resolution of your PICO Question

Narrate/Write your PICO Question & Why is it important.Summarize the Study FindingsSummarize the weaknesses, biases, NNT and NNH, Sens., Specif., LR etc.Indicate the Level of Evidence & whether you are going to apply the findings to your patient.

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Useful LinksEBM Glossary of Terms: http://www.cebm.net/glossary/EBM Calculators: http://ktclearinghouse.ca/cebm/practise/ca/calculatorsEBM NNT, LR etc. Websites:http://ktclearinghouse.ca/cebm/toolboxhttp://www.thennt.com/EBM Critical Appraisal Worksheets: http://ktclearinghouse.ca/cebm/practise/ca/worksheetsDiagnosis worksheetHarm worksheetPrognosis worksheetSystematic review (of therapy) worksheetTherapy worksheet

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