A cohort study of coffee drinking and anxiety was conducted at a university campus. There was a total of 30,000 freshmen who participated. Ten thousand (10,000) were coffee drinkers and 20,000 were not. Of the coffee drinkers, 500 developed anxiety during the 4-year follow-up period. Of the non-coffee drinkers, 200 developed anxiety during the same time period. Assume that no one in the population died or was lost during the follow-up period. Construct a two by two table with the given data, making sure that you have labeled the margins correctly.
-Calculate the population risk difference using the given data. The numeric value of the population risk difference is:

Question

Quizplus · Accepted Answer

The population risk difference is the difference in the risk of developing anxiety between coffee drinkers and non-coffee drinkers. The risk of developing anxiety among coffee drinkers is 500/10,000 = 0.05, and the risk of developing anxiety among non-coffee drinkers is 200/20,000 = 0.01. Therefore, the population risk difference is 0.05 - 0.01 = 0.04, or 4 per 100.

A Cohort Study of Coffee Drinking and Anxiety Was Conducted