Epidemiology for Public Health Practice 5th Edition by Robert Friis,Thomas Sellers

تمرين 5

A cohort study was conducted to study the association of coffee drinking and anxiety in a population-based sample of adults. Among 10,000 coffee drinkers, 500 developed anxiety. Among the 20,000 noncoffee drinkers, 200 cases of anxiety were observed. What is the relative risk of anxiety associated with coffee use?