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Critical Appraisal Resources

An overview of resources on the web to support critical appraisal.

Levels of Evidence

OCEBM - Levels of Evidence [ Website ] identifies levels of evidence from 1 -5 appropriate for particular types of question. The Levels of Evidence model is a reinterpretation of the Hierarchies of Evidence model, responding to criticisms that is was inflexible. The Hierarchies of Evidence model is more typically represented as a pyramid.