Friend Selection and Influence Effects for First Heavy Drinking Episode in Adolescence.

Objective: Heavy alcohol consumption has both immediate and longer-term risks for adolescents. Using a dynamic network modeling approach, this study investigated the role of adult supervision and affiliation with heavy drinking friends in predicting the risk of a first heavy drinking episode in a community sample of adolescents. Method: Two cohorts of ninth grade youth (n = 1.220. 48% male) from seven communities were surveyed three times over the course of the school year (fall. winter, and spring), each time assessing their friendship networks, whether they had ever experienced a heavy drinking episode, frequency of heavy drinking over the past month, and the amount of unsupervised time spent with each of their friends over the past month. Results: Participants were more likely to form friendships with classmates with similar recent heavy drinking behavior, but similarity on adult supervision of time spent with friends had no effect on friendship selection. A negative interaction was observed between these two similarity effects, implying that they were antisynergistic. Risk for a first heavy drinking episode was greater for youth with friends who had experienced such an episode already. This effect was no stronger if these friends had more such episodes in the previous 30 days but was marginally stronger if the friends reported less adult supervision. Conclusions: Heavy drinking -related friendships increase the risk of a first heavy drinking episode. Adult supervision of time spent with friends may reduce this risk. Results support interventions that target the spread of heavy drinking through adolescent social ecosystems, in addition to targeting the most at-risk individuals.