The original COGA subjects were recruited beginning in 1990 at six data gathering centers following approval by each site’s Human Subjects’ Protections Committee. These subjects: a) had been patients with alcohol dependence in alcohol and drug treatment programs who had multiple first-degree relatives who met criteria for the same disorder, or b) were comparison subjects from various community samples (Bucholz et al., 1994; Hesselbrock et al., 1999). In 2009, the protocol shifted to 12-to-21year-old relatives of the original subjects for whom at least 1 parent had been interviewed in the original study. The resulting members of the COGA Prospective Youth Sample have been followed every 2 years. As of December 2016, the youth sample included 3791 individuals, 1355 of whom were age 12 to 26 and had completed the SRE, and the Barratt Impulsivity questionnaire. Of these, 117 were excluded because they had already developed alcohol dependence as defined in the Fourth Diagnostic and Statistical Manual (DSM-IV) criteria (American Psychiatric Association, 2000). Of the remainder, 1028 had Baseline evaluations (the time the SRE was completed) and one (174) or two
