Case-control study is better than cohort study in which aspect -

Ans. is 'c' i.e., Shorter duration Case control studyCohort study1. Proceeds from "effect to cause"Proceeds from "cause to effect"2. Starts with the diseaseStarts with people exposed to risk factor or suspecte cause3. Tests whether the suspected cause occurs more frequently in those with the disease than among those without the diseaseTests whether disease occurs more frequently in those exposed, than in those not similar exposed4. Usually the first approach to the testing of a hypothesis, but also useful for exploratory studiesReserved for testing of precisely formulated hypothesis5. Involves fewer number of subjectsInvolves larger number of subjects.6. Yields relatively quick resultsLong follow-up period often needed, involving delayed results7. Suitable for the study of rare diseases.Inappropriate when the disease or exposure under investigation is rare.8. Generally yields only estimate of RR (odds ratio)Yields incidence rates, RR as well as AR.9. Cannot yield information about diseases other than that selected for studyCan yield information about more than one disease outcome.10. Relatively inexpensiveExpensive