EBM: Critical Appraisal of an Article on Therapy

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

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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: Prospective, blind comparison to a gold standard Other:Date 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 Abstract/Conclusion from the Abstract here

Paste Abstract here: use several slides if it is long-remember the 6X6 rule in power-point presentations!

My Appraisal MapAppropriateness of chosen Title?Trustworthy Authors?Truthful Abstract?Comprehensiveness of Introduction section?Relevance: Importance for PracticeValidity: Appropriate Methodology (Validity: Internal)?Results: Trustworthy Results?Applicability?Impact of Findings on Current Practice and Future Recommendations?

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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 SchemeRelevanceImportant outcome:Is target disorder dangerous if left Undiagnosed?Does effective treatment exists?Common Problem:Is target disorder common enough?Will change the practice? Will information from test lead to change of management beneficial to patients? Does treatment thresholds differ? (NB to be answered after the result)

Apply Your Appraisal SchemeValidityWas there an independent, blind comparison with a reference standard?Is reference standard used acceptable?Blind interpretationIndependent: Index test is not part of Gold standard test.

Apply Your Appraisal SchemeValidityDid the patient sample include an appropriate spectrum of patients towhom the test will be applied? (Spectrum Bias)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 SchemeValidityInterventions: Were the tests method describedclearly enough to permit replication? Preparation of patient?Performance of test?Analysis and interpretation of results?Test precision and correctness Reproducibility: Inter & Intra-observer Bias)

Apply Your Appraisal SchemeValidityDid investigators perform the same reference standard to all patients regardless of the results of the testunder investigation?Were both reference standard and test applied to all patients?Verification (workup) Bias

Apply Your Appraisal SchemeResults clinical significance (in MP : Magnitude & Precision) What likelihood ratios are associatedwith the range of possible test results?Calculate and interpret LR, Sn and Sp(Diagnostic and Treatment Thresholds)

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 Will the test be applicable and well interpreted in my practice setting?Feasible testTrained operatorAre the results applicable to patients in my practice?Similar distribution of disease severity?Compelling reasons why the results should not be applied?

Apply Your Appraisal SchemeApplicability I (in IPPP: Intervention Population - Preferences-Potential Benefits - Harm What are your patients preferences?Invasive vs. non invasive toolsCostsWill the reproducibility of the test result and its interpretation be satisfactory in my setting?

Resolution of your PICO Question

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

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Resolution of your PICO Question: Recommendations

New Research: Is there a need to do more research of the subject? Y N Suggested research if the answer is yes:Audit: Is there a need to audit your practice? Y N Suggest an audit cycle.Publication: Is it worth publishing your Journal Club presentation in an EBM CAT journal or website? May be start your own JC website?

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Open the Floor for Discussion

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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