Indices of illegal drug use and abuse/dependence and alcohol dependence were collected in the 1992 telephone diagnostic interview, based on the Diagnostic Interview Schedule (DIS-III-R) (Robins, Helzer, Cottler, & Goldring, 1989). For cannabis, cocaine, stimulants, sedatives, opiates, and hallucinogens/PCP, respondents were asked whether they had ever used each drug, their age at initiation, and whether they had used more than 5 times. Respondents who had used a drug more than 5 times were asked abuse and dependence questions based on DSM-III-R. Because of the low prevalence of illegal drug abuse in this sample, the illegal drug abuse/dependence diagnoses were combined. Alcohol dependence was also assessed using DSM-III-R criteria.
