Skip to Main Content

Gerstein Science Information Centre

Evidence-Based Practice

6S Pyramid

Acknowledgements: McMaster University Guide:


Integrating information from the lower levels of the hierarchy with individual patient records, systems represent the ideal source of evidence for clinical decision-making. An example of a system in this context would be a Clinical decision support system (CDSS).

Learn more: Biomedical informatics: computer applications in health care and biomedicine


Summaries are regularly updated clinical guidelines or textbooks that integrate evidence-based information about specific clinical problems

Clinical Practice Guidelines

Evidence-Based Texts & Point-of-Care Tools

Synopses of Syntheses

Synopses of syntheses, summarize 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.


  • Database of Abstracts of Reviews of Effectiveness (DARE)
    • Focused primarily on systematic reviews that evaluate the effects of health care interventions and the delivery and organisation of health services.
  • Economic Evaluation Database 
    • Focused primarily on the economic evaluation of health care interventions and aims to help decision makers interpret an increasingly complex and technical literature. 
  • Health and Technology Assessment Database
    • Focused on completed and ongoing health technology assessments from around the world. 


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

Synopses of single studies summarize evidence from high-quality studies. The following evidence-based abstract journals are the best place to find this type of information:

Single Studies

Studies represent unique research conducted to answer specific clincial questions.

Controlled Vocabulary Databases - use subject headings for high-specificity searching

Multidisciplinary Citation Indexes - keyword searching only


Meta-Searches search for evidence across multiple resources.  These tools return information from all levels of the pyramid:

Grey Literature

Grey Literature is any literature that has not been published through traditional means. It is often excluded from large databases and other mainstream sources.

For grey literature resources, see the Grey Literature tab on the Comprehensive Searching in the Health Sciences Guide 

Search Tips

Search Tips and Tricks for Searching Heavily Distilled Products

  • Consider browsing by disease, as this often leads to the “highest level” of article
  • If no index to contents exists, try a disease search, then browse results
  • The more distilled the product, the more general the search!
  • These are small databases; your results will be small even for one-word searches! e.g. search by drug or disease name, and add no qualifiers
  • Consider synonyms, spelling variations, word variations e.g. prevention = prophylaxis = primary prevention e.g. behavior = behaviour e.g. prozac = fluoxetine, also consider ssri, tradenames
  • Omit needless words that may remove good results!
  • Pubmed Clinical Queries - filter selection handles common aspects, e.g. treatment, so you don’t need those “qualifier” words
  • Start with a basic search.  If results are too large, add qualifiers one by one, not all-at-once

Search Tips and Tricks for Less Distilled Products and Search Engines

  • Your goal is to eliminate the junk and let the professional, high-quality literature filter to the top of the results list.
  • Think of words that the author would use
  • Use professional vs. layperson language E.g. Hypercholesterolemia not high cholesterol

The less distilled the product, the more specific the search!