Clinical criterion counts for alcohol (AUDSX), nicotine (NDSX), and cannabis (CUDSX) were obtained from the reliable and valid Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA) [38, 39]. Criterion counts for alcohol and cannabis use disorder were made according to DSM-5 [40] and thus each had a possible range of 0–11. The criterion count for NDSX came from the Fagerström Test for Nicotine Dependence [41] and had a possible range of 0–10. The criterion count distributions showed right skews; to address this in inferential analyses, we applied a logarithmic transformation (left anchored at 1).
