<prompt> In a case control study on smoking and lung cancer, out of 35 lung cancer patients, 33 are smokers. Out of 82 controls, 27 are non smokers. Find the odds ratio:0.218.14.12.1  <response>: Cancer Controls without cancer Smokers 33 a 55 b Non smokers 2 c 27 d Total 35 82 Odds ratio axdbxc 33x2755x2 8.1 REMEMBER: while constructing table keep exposure in rows e.g.: smokers vs non smokers here and presence or absence of disease condition in columns e.g.: cancer vs no cancer Ref: Parks textbook of Preventive and Social Medicine, 21stedition, page-69. 