Which of the following is the STRONGEST design for establishing causality between an exposure and an outcome?
- A Prospective cohort study
- B Case-control study
- C Systematic review of RCTs ✓
- D Cross-sectional study
Correct answer: C. Systematic review of RCTs
Explanation
In the hierarchy of evidence, a systematic review and meta-analysis of well-conducted RCTs occupies the highest level because it synthesises the least-biased individual study design (RCT) across multiple studies. A prospective cohort is strong but subject to confounding. Case-control and cross-sectional studies are lower in the hierarchy due to greater bias susceptibility.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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