Drinks per drinking day (DDD) were assessed using the Form 90 (Miller and Del Boca, 1994). The primary goal of the Form 90 interview is to gather information regarding a person’s drinking behavior over a 3-month (90-day) period using a calendar method, such that data can be summarized weekly or monthly during the assessment window. For the current study, DDD over the previous 30-day period was categorized into (1) nondrinking, defined as zero DDD; (2) moderate drinking, defined as five or fewer DDD for men or four or fewer DDD for women; and (3) heavy drinking, defined as more than five DDD for men and more than four DDD for women. This categorization was based on the definition of heavy drinking provided by the National Institute on Alcohol Abuse and Alcoholism (2004).
