In a population of 10000, 2100 were alcoholic. 70 alcoholics among these developed cirrhosis and 23 non-alcoholic developed cirrhosis what is attributable risk -

Ans. is 'd' i.e., 90% o In a population of 10000 -i) Exposed person = 2100ii) Nonexposed person = 7900 (10000-2100)iii) Incidence of disease among exposed=70----2100x 1000 = 33 per 1000 exposed person iv) Incidence of disease among nonexposed =23----7900x 1000 = 3 per 1000 nonexposed persono Attributable risk is the difference in incidence rates of disease (or death) between an exposed group and nonexposed group.AR =Incidence of disease in exposed - Incidence of disease in unexposed--------------------------------------------------------Incidence of disease in exposedx 100 AR =33-3----33x 100 = 90%o That means 90% of cirohosis among alcoholics is due to alcohol exposure.