In a prospoective study comprising 10,000 subjects, 6000 subjects were put in beta carotene and 4000 were not. 3 out of the first 6000 developed lung cancer and 2 out of the second 4000 developed lung cancer. What is the interpretation of the above results?
This is a prospective study or coho study. Risk is estimated as relative risk and attributable risk. Relative risk =incidence of disease in exposed/incidence of disease in unexposed. incidence in exposed = 3/6000 Incidence in unexposed =2/4000 Relative risk=1 Relative risk = 1 implies no association between exposure and disease under study; no association between beta-carotene intake and lung cancer Ref: Parks textbook of preventive and social medicine, 23rd Edition Pg no: 78
Beta carotene is protective in lung cancer
Beta carotene and Lung cancer have no relation to each other
The study design is not sufficient to draw any meaningful conclusions
Beta corotene is carcinogenic
Epidemiology