Out of more than 11,000 subjects who participated in COGA, a case-control series of unrelated individuals was selected for SAGE. COGA recruited subjects in Hartford, Connecticut; Indianapolis, Indiana; Iowa City, Iowa; New York City, New York; San Diego, California; St Louis, Missouri; and Washington, DC. For inclusion in SAGE, cases had to meet life-time criteria for DSM-IV alcohol dependence, the majority of cases were recruited from alcoholism treatment centers. Control subjects, were both biologically unrelated to cases, and had consumed alcohol but never experienced any significant alcohol or drug-related problems, according to the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA)23. COGA contributed 212 individuals with DSM-5 cocaine use disorder (all 212 of which also had DSM-5 alcohol use disorder) and 389 individuals without cocaine use disorder (271 with DSM-5 alcohol use disorder, 118 alcohol drinkers without DSM-5 alcohol use disorder).
