Evidence-based Medicine Toolkit

Appraising systematic reviewsIs thesystematicreview valid?Are the resultsimportant?1 Is it a systematic review of high-qualitystudies which are relevant to your question?2 Does the methods section adequatelydescribe:• a comprehensive search for all the relevantstudies?• how the reviewers assessed the validityof each study?3 Are the studies consistent, both clinicallyand statistically?Are they clinically significant?If the review reports odds ratios (ORs), youcan generate an NNT if you have an estimateof your patient’s expected event rate(PEER).NNT =1 – {PEER x (1 – OR)}(1 – PEER) x PEER x (1 – OR)How precise are the results?Can the resultshelp you?See p. 31.27