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Evidence-Based Medicine: Levels of Evidence

Hierarchy of Evidence-Based Resources

Adapted from DiCenso A, Bayley L, Haynes RB. ACP Journal Club. Editorial: Accessing preappraised evidence: fine-tuning the 5S model into a 6S model. Ann Intern Med. 2009;151(6):JC3.

Foreground Question Resources

Systems Electronic medical records Summaries Regularly updated clinical guidelines or textbooks that integrate evidence-based information about specific clinical problems. ACP Clinical Guidelines National Guidelines Clearinghouse Clinical Key - Guidelines Dynamed Plus TRIP AccessMedicine UpToDate Synopses of Syntheses Summarizes the information and draws conclusions found in systematic reviews and meta-analyses. NHS Centre for Reviews and Dissemination (CRD) Cochrane Evidence Summaries HealthEvidence
Syntheses Systematic reviews of meta-analyses. A comprehensive summary of all the evidence surrounding a research question. . The Cochrane Library PubMed Clinical Queries Google Scholar Synopses of Single Studies Summaries of evidence from high-quality studies. . BMJ Clinical Evidence ACP Journal Club
Single Studies Unique research conducted to answer specific clinical questions. PubMed Ovid EMBASE Web of Science Scopus Google Scholar CINAHL PsycINFO Adapted from: https://hslmcmaster.libguides.com/friendly.php?s=ebm