Best epidemiological study is -
Ans, is 'b' i.e., Meta-analysis o Here are the different epidemiological studies with decreasing order of accuracy to test the association between risk factor and diseaseSystematic review and meta-analysis - Overall most reliableRandomized controlled trials (controlled clinical trails) - Most reliable individual study.Retrospective (Non-concurrent''historic) Cohort study.Prospective (concurrent) Cohort study.Case control studyCross-sectional studyEcological study
RCT
Meta-analysis
Cohort study
Case-control study
Analytical Epidemiology