To ensure that alcohol naive participants were not included in reports of alcohol-related aggression, these items were skipped for participants who either: (I) reported having never consumed at least three drinks within a 24-hour period, or (II) reported that they had never consumed alcohol regularly (i.e., had at least one alcoholic drink per month for at least six consecutive months) and reported that that they had never been drunk (to the point where their speech was slurred or they were unsteady on their feet). To exclude drug naive participants from reports of drug-related aggression, each item that corresponded to a specific drug-type (i.e., cocaine, opiates, sedatives, stimulants, and other drugs) was skipped for participants who reported that they had not used that given drug-type at least 11 times in their life. In COGA’s phase 1 of data collection, the fourth non-substance-related aggression item was also skipped for participants who did not have at least two instances of conduct problems before the age of 18, lifetime alcohol problems, lifetime marijuana problems, or lifetime drug problems.
