the sample had always abstained from alcohol, the majority (∼93%) had consumed alcohol in the previous year, with 7.6% and 5.5% of male and females, respectively, reporting that they drank alcohol on a daily basis. With respect to alcohol dependence, male participants were approximately three fold more likely to meet a lifetime diagnosis of either DSM-IIIR (23.6%) or DSM-IV (18.2%) dependence than female twins. However, ∼37% of males and ∼70% of females did not report any symptoms of alcohol dependence. Similarly, most twins did not meet lifetime criteria for DSM-IV alcohol abuse.
