Which study design is most appropriate to investigate the causes of a rare disease?
Answer and explanation
Correct answer: B. Case-control study
- Step 1: Rare outcomes need efficient designs.
- Step 2: Case-control studies start with cases and select controls, so they need fewer participants.
Answer
Case-control study.
Why not the others: Large prospective cohort study: A cohort study would need very large numbers to observe enough cases. Cross-sectional survey: Cross-sectional surveys cannot establish temporal relationship well. Randomised controlled trial: Randomised trials cannot ethically allocate harmful exposures.
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