Key findings from these results are that: (1) low OXTR risk youth associate with low substance-using friends in the intervention but not the control condition, (2) a main effect of substance-using friends on adolescents’ own alcohol use exists across all combinations of OXTR and intervention conditions, and (3) the three-way interaction is driven by adolescents with higher OXTR risk who associate with lower substance-using friends reporting somewhat higher alcohol use in the intervention than similar adolescents’ reports in the control group. The difference in alcohol use levels captured by this interaction was small and occurred at the low end of the alcohol use scale.
