Find the best available evidence

Original Editor - Rachael Lowe

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Levels of evidence
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This has been adapted from Sackett, Straus and Richardson (2000)[1]

Level of Evidence
Type of Study
1a
Systematic reviews of randomized controlled trials (RCTs)
1b
Individual RCTs with narrow confidence interval
2a
Systematic reviews of cohort studies
2b
Individual cohort studies and low-quality RCTs
3a
Systematic reviews of case-control studies
3b
Case-controlled studies
4 Case series and poor-quality cohort and case-control studies
5 Expert opinion


References[edit | edit source]

  1. Sackett DL, Straus SE, Richardson WS, et al. Evidence-Based Medicine: How to Practice and Teach EBM. 2nd ed. Edinburgh, Scotland: Churchill Livingstone Inc; 2000:173-177.