Which study design provides the STRONGEST evidence for causality in the evidence hierarchy?
- A Prospective cohort study
- B Systematic review and meta-analysis of RCTs ✓
- C Randomized controlled trial
- D Cross-sectional study with a large sample size
Correct answer: B. Systematic review and meta-analysis of RCTs
Explanation
The evidence hierarchy (Oxford Centre for Evidence-Based Medicine) places systematic reviews and meta-analyses of RCTs at the top (Level 1), followed by individual RCTs, then prospective cohort studies, case-control studies, and expert opinion at the bottom. This is because systematic reviews pool the strongest individual study design (RCTs) and reduce random error through combined analysis.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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