The Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA) (Bucholz et al., 1994; Hesselbrock et al., 1999) was adapted for interview via telephone and used to collect lifetime diagnostic data from parents and twins at Wave 1 and from twins at Wave 4. Detailed histories of alcohol, cigarette, and cannabis use and related problems were obtained from twins in Waves 1 and 4. Wave 5 data collection was also conducted with SSAGA-based telephone interviews, but differed from earlier assessments in its focus on obtaining updated rather than lifetime psychiatric and substance use histories. (The majority of questions referred to experiences from the previous 24 months, the approximate period of time between Wave 4 and Wave 5 assessments.)
