Three phenotypes were examined: lifetime sum CD symptoms in adolescence/young adulthood, sum AAD symptoms in adolescence/young adulthood, and sum AAD symptoms in adulthood. CD was assessed in adolescents using the Diagnostic Interview Schedule for Children (DISC) (Shaffer et al. 1993). Early study participants were evaluated with DISC 2.3, which assessed DSM IIIR diagnoses. Later participants were assessed using DISC IV, which assessed DSM IV diagnoses. CD was assessed for subjects over the age of 18 utilizing the Diagnostic Interview Schedule (DIS) (Robins et al. 1981), and, similar to the DISC, began with DSM IIIR diagnoses and finished with DSM IV diagnoses. DSM IV defined AAD were assessed with the Composite International Diagnostic Interview – Substance Abuse Module (CIDI-SAM) (Cottler and Keating 1990). As comorbidity is high in this sample, subjects with comorbid drug use were not excluded (Stallings et al. 2003). Each variable was standardized and analyzed as described below.
