Which of the following study designs provides the highest level of evidence for establishing causation in clinical epidemiology?
- A Prospective cohort study
- B Randomized controlled trial ✓
- C Systematic review with meta-analysis of observational studies
- D Case-control study with proper matching
Correct answer: B. Randomized controlled trial
Explanation
The randomized controlled trial (RCT) sits at the apex of the hierarchy for establishing causation because random allocation eliminates selection bias and balances known and unknown confounders between groups. A systematic review with meta-analysis of RCTs would be higher still, but option C specifies observational studies only. Cohort studies cannot fully control for unmeasured confounding.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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