The proposed design and network analytic methods will allow the investigators to investigate the extent to which an intervention conducted with careful attention to network connection is transmitted to others (Aim 1), how those effects occur (Aim 2), conditions under which those effects are more likely (Aim 3), and how the connections themselves change as a function of the intervention (Aim 4).
AIM 1. To investigate the efficacy of targeted Brief Motivational Intervention for reducing heavy drinking and alcohol consequences in network members who received no intervention. The investigators expect that heavy drinking participants residing in dormitories assigned to BMI but who receive no intervention will show lower frequency of heavy drinking and alcohol consequences at follow-up than their comparison group in NHC dormitories (n = 480; 240 in each condition).
AIM 2. To identify the social influence mechanisms through which the intervention effect is conveyed. The investigators expect that reductions in the following social influence mechanisms will mediate the indirect intervention effect: (1) behavioral modeling of heavy drinking; (2) social reinforcement for drinking or not drinking; (3) offers and provision of alcohol; (4) the perception of peer heavy drinking (descriptive norms); and (5) the perception of peer approval of heavy drinking (injunctive norms).
AIM 3. To identify the network and relationship features that moderate intervention efficacy.
3A. Proximity to Intervention. The investigators expect that heavy drinking network members who: (1) have first-degree ties (i.e., a direct tie) with intervention recipients, (2) have a higher proportion of intervention recipients in their close network (i.e., have the highest exposure to transmitted intervention effects), and (3) have an intervention recipient as a roommate will show the strongest indirect intervention effect.
3B. Quality of Peer Relationships. The investigators expect that stronger relationships with intervention recipients as measured by: (1) best-friend status, (2) higher perceived relationship closeness, (3) higher perceived social support, and (4) reciprocated network nominations, will be related to greater indirect intervention effects.
AIM 4. To investigate the intervention effect on personal-level network position and on drinking-based selection in the network.
4A. Network position. Differences between the intervention recipients in the BMI and NHC groups at follow-up will be investigated on: (1) betweenness centrality (how often the participant falls on the shortest path between two others) and (2) prestige (number of nominations of the participant by others). There is little literature on how network positions change following behavioral intervention, so directional hypotheses are not proposed.
4B. Drinking-based selection. At follow-up, the investigators expect less drinking-based selection in the BMI group compared to the NHC group.
