All adolescents and adults who participated in the Collaborative Study on the Genetics of Alcoholism between September 2005 and September 2017 were eligible for this study (n = 3,834 in 904 families). Only one subject was randomly drawn from each family to prevent associations of observations within families. Correlation within each site was accounted for using bootstrap resampling at the site level to estimate standard errors. The sample encompassed 904 participants and was randomly divided in two subsamples (20% for development and 80% for validation). Sex, age, household income, and self-reported race for these samples are included in Table 1.
