An understanding of the 6 'S' Hierarchy of Evidence is the foundation for efficient and effective retrieval of evidence-based research relating to clinical practice.
The resources on this page will help you find evidence for the speicifc level of the hierarchy you are interested in.
For more search tips, check out the Health Sceinces Library's Database Fundamentals Tutorial.
[Adapted from DiCenso, Bayley and Haynes (2009). ACP Journal Club. Editorial: Accessing pre-appraised evidence: Fine-tuning the 5S model into a 6S model. Annals of Internal Medicine, 151(6):JC3-2, JC3-3.]
Integrating information from the lower levels of the hiearchy with individual patient records, systems represent the ideal source of evidence for clinical decision-making.
Summaries are regularly updated clinical guidelines or textbooks that integrate evidence-based information about specific clinical problems.
Synopses of syntheses, summarize and critically appraise the information found in systematic reviews. By drawing conclusions from evidence at lower levels of the pyramid, these synopses often provide sufficient information to support clinical action.
Commonly referred to as a systematic review, a synthesis is a comprehensive summary of all the evidence surrounding a specific research question.
Synopses of single studies summarize evidence from high-quality studies, including some level of critical appraisal.
Studies represent unique research conducted to answer specific clincial questions.