Calculate the odds ratio of an adult having a head injury as a function of whether or not that adult wears a helmet. (Why could you not do the same thing for children?)

Dabbs and Morris (1990) investigated the effects of elevated testosterone levels in a representative sample of U.S. adult males (mean age 37). Subjects were classified as High (upper 10%) or Normal on testosterone, as high or low on socioeconomic status (SES), and as engaging (or not engaging) in adult delinquency. Their data follow.

Low SES High SES Normal High Normal High Delinquent Testosterone Testosterone Testosterone Testosterone Yes 190 62 53 3 No 1104 140 1114 70