What makes group MET work? A randomized controlled trial of college student drinkers in mandated alcohol diversion.

Nationally, college drinkers exhibit the highest rates of alcohol consumption and represent the largest percentage of problem drinkers. Group motivational enhancement therapy (GMET) has been found to catalyze problem drinking reductions among college student samples. Although research supporting the use of single-session GMET in college samples (general and mandated) is emergent, no studies have evaluated a comprehensive model of the potential active ingredients of this group intervention. College students (N = 206; 88% White; 63% men; M age = 18.6) mandated to a university alcohol diversion program were randomly assigned to 1 of 3 conditions: the standard-of-care 2-session "Focus on Alcohol Concerns" education group (FAC), a single GMET, or a single alcohol information-only control group (AI) to evaluate the role of 5 putative mediators: readiness to change, self-efficacy, perceived risk, norm estimates, and positive drinking expectancies. At 3- and 6-month follow-ups, GMET students demonstrated greater reductions in problem drinking outcomes (drinks per drinking day, hazardous drinking symptoms, and alcohol-related problems). Of the 5 mediators proposed, only self-efficacy emerged as a significant mediator.