The study was approved by the University of Chicago Institutional Review Board. The design was a double-blinded, placebo-controlled, within-subjects study of responses to alcohol challenge, with longitudinal follow-up of alcohol drinking behaviors and problems in 190 non-alcohol-dependent social drinkers. The laboratory phase (March 2004 to July 2006) included three sessions. After laboratory testing, each participant entered the longitudinal follow-up phase, with no participants lost to follow-up. Follow-ups were conducted from March 2005 to October 2012, at the end of years 1, 2, 4, 5, and 6 after laboratory challenge. In this report, we focus on the 104 nonalcoholic, heavy social drinkers in the sample who met inclusion criteria (consume five or more drinks for men [four for women] on an occasion one to five times per week as their predominant adult pattern [i.e., at least the past 2 years], with at least 10 but no more than 40 standard drinks weekly). The binge criteria were consistent with Substance Abuse & Mental Health Services Administration and National Institute on Alcohol Abuse and Alcoholism guidelines (24,25); the weekly consumption criteria assured overall regular alcohol exposure (26).
