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Dr Sedgwick has summarized the cohort study very nicely. But I have a query pertaining to its analysis. The cohort studies are basically incidence studies and largely are prospective and incidence of disease among exposed divided by incidence among unexposed is relative risk which is the analysis of a cohort study. My query is that BMI is not the only risk factor, there are other risk factors too. e.g. age (75 years is riskier than 40 years), family history etc. (1). Can we apply multiple logistic regression and determine Odds ratio (which will adjust the confounding) instead of risk ratio. Kindly guide me.