Study Design & Hierarchy of Evidence for USMLE
From strongest to weakest: Systematic Reviews, RCTs, Cohort Studies, Case-Control Studies, Cross-Sectional Studies, Case Reports, Expert Opinion.
Key Associations
- RCT and Cohort Studies → Relative Risk (RR)
- Case-Control Studies → Odds Ratio (OR) only
- Cross-Sectional Studies → Prevalence