What type of research or 'evidence' is the best to use?
The hierarchy of evidence attempts to rank research in order of importance. It can be broadly divided into two categories; filtered (pre-appraised) and unfiltered (original data).
Filtered
1. Systematic reviews and meta-analysis
2. Critically appraisal articles
Unfiltered
3. Randomized controlled trials
4. Cohort and case control studies
5. Case studies
6. Expert and anecdotal opinion
To find out more about the evidence pyramid take a look at this video from the Cushing/Whitney Medical Library at Yale University.
Clinical information resources are usually classified by the extent to which they are critically appraised. We often use a pyramid diagram to distinguish two different tiers of resources.
This tutorial explains the differences of the two tiers and shows how various clinical resources fit into the pyramid model.