Beginning in late 2004, adolescent and young adult offspring in the COGA families who were born from 1982 onward (aged 12-22 at inception) and with at least one parent who had been interviewed in the original COGA study, were recruited into the Prospective Study. Every 2 years, participants are administered a comprehensive structured psychiatric diagnostic interview covering histories of alcohol, tobacco and illicit drug use, problems and disorders, as well as other psychiatric disorders, to obtain DSM-IV and DSM-5 (for substances) diagnoses. Questionnaires that focus on personality, impulsivity, drinking motives, response to ethanol, among others, are included. Subjects undergo neuropsychological and neurophysiological protocols that focus on resting state and cognitive function, including aspects of frontal lobe functioning. About 75% of the sample has been genotyped. Supplemental Table 1 contains the specific assessments included. All subjects provided written informed consent, and the study was approved by institutional review boards at each COGA site.
