Subjects were participants in the multi-site Collaborative Study on the Genetics of Alcoholism (COGA), a project designed to explore behavioral, biochemical, genetic, neuropsychological, environmental, and neurophysiologic contributions to AD in high-risk families (defined as having at least one adult proband treated for AD) and community comparison families (Begleiter et al., 1995). Since 2005, COGA has used a prospective design focusing on participants who were 12 to 21 years of age at the start of this phase; these participants are the offspring and non-first-degree family members (e.g., nieces, nephews, grandchildren) of the original probands in high-risk and comparison families, and are followed-up every 2 years. The subject pool for this study consisted of the 820 adolescents from our previous study (Kuperman et al., 2013) who were 14 to 17 years old at the time of their assessments during the years of 2005–2007. Institutional Review Boards at all sites reviewed and approved study design. Parents provided consent for all offspring below age 18; children age 13 and older also provided consent, and children age 12 provided assent.
