Main Outcomes of M-Bridge: A Sequential Multiple Assignment Randomized Trial (SMART) for Developing an Adaptive Preventive Intervention for College Drinking

Objective: The goal was to develop a universal and resource-efficient adaptive preventive intervention (API) for incoming first-year students as a bridge to indicated interventions to address alcohol-related risks. The aims were to examine: (a) API versus assessment-only control, (b) the different APIs (i.e., 4 intervention sequences) embedded in the study design, and (c) moderators of intervention effects on binge drinking. Method: A sequential multiple assignment randomized trial (SMART) included two randomizations: timing (summer before vs. first semester) of universal personalized normative feedback and biweekly self-monitoring and, for heavy drinkers, bridging strategy (resource email vs. health coaching invitation). Participants (N = 891, 62.4% female, 76.8% White) were surveyed at the end of first and second semesters. The primary outcome was binge drinking frequency (4+/5+ drinks for females/males); secondary outcomes were alcohol consequences and health services utilization. Results: API (vs. control) was not significantly associated with outcomes. There were no differences between embedded APIs. Among heavy drinkers, the resource email (vs. health coach invitation) led to greater health services utilization. Moderator analyses suggested students intending to pledge into Greek life benefited more from any API (vs. control; 42% smaller increase from precollege in binge drinking frequency). Conclusions: Although overall effects were not significant, students at high risk (i.e., entering fraternities/sororities) did benefit more from the intervention. Furthermore, the resource email was effective for heavier drinkers. A technology-based strategy to deliver targeted resource-light interventions for heavy drinkers may be effective for reducing binge drinking during the transition to college. What is the public health significance of this article? The study examined the effect of adaptive preventive interventions (APIs), which are interventions tailored over time to better meet the needs of individuals, on college student drinking. In this case, the APIs did not have overall effects for the student population of incoming first-year college students, but the APIs did reduce binge drinking for students intending to pledge into fraternities or sororities. For heavy-drinking students, a resource email providing a link to an online intervention (i.e., Web-BASICS) was more effective in increasing health services utilization than an invitation to chat with an