When drinking less is more: Differential effects of an alcohol intervention in university students

Background Problematic alcohol use is a common phenomenon to be experienced within university context. It is often associated with overestimation of peers' alcohol use. We hence conducted a social norms intervention (SNI) in university students and hereby report its (differential) efficacy. Objectives Examination of the intervention's efficacy and its possible differential effects. Methods The intervention was integrated into regular health monitoring at Freie Universitat Berlin. We included only students who participated in the health survey for two consecutive times, required feedback for their alcohol use, overestimated their peers' alcohol use and showed problematic alcohol use. Students who considered the feedback were assigned to the intervention group and those who did not consider the feedback were assigned to the control group. Results The social norms intervention resulted in a significant reduction of norm overestimation and general alcohol use in the intervention group. No differences in problematic alcohol use and binge drinking could be observed. Students with highest-risk alcohol use showed reduced alcohol use and norm overestimation. Students with slightly elevated alcohol use did not show a reduction in alcohol use, but in norm overestimation. Conclusions The SNI proved its efficacy. Students with higher levels of alcohol use benefit more from the intervention. Students with slightly elevated alcohol use do not show behavioral changes. Consequences and limitations, also with regard to SNI, are discussed.