Method: The sample includes 959 nightclub patrons who formed 359 groups recruited from seven clubs, across 41 different events. The median age was 26 and 45.3% were female. All data collection was attained anonymously. Outcome variables examined include: overall number of the group’s safety actions taken to keep group members safe, the highest number of safety actions by any single group member, and BAC at exit. Mixed model regressions examined the main effect of group composition and its interaction with the intervention as a predictor of outcomes after controlling for individual and group characteristics.
Results: Most individuals were in mixed gender groups (53%), with 30% in all male groups, and 16.8% in all female groups. Group composition significantly interacted with intervention condition in some models. Being assigned to the intervention condition was related to higher numbers of safety actions by any single member in all female groups and mixed gender groups, but not in all-male groups. There were no significant interactions for intervention status by group composition for either BAC at exit or the number of group actions taken as assessed by the overall group.
Conclusions: Females may be more open to implementing safety strategies and future studies could explore how to better engage all male groups in prevention strategies. However, group composition was not related to outcomes for two of our outcome variables, suggesting that the intervention was robust across different group gender compositions.