A Hybrid Type 1 Randomized Controlled Trial of an Online and Text-Messaging Intervention to Prevent Alcohol and Cannabis Initiation, Escalation, and Consequences Among First-Year College Students

Building on promising pilot findings, this study will employ a Hybrid Type 1 Effectiveness-Implementation RCT to evaluate the effectiveness of a novel intervention for first-year college students who abstain from or use alcohol and cannabis lightly, compared to assessment-only control. Aim 1 will finalize the intervention through student feedback to ensure relevance and engagement and Aim 2 will test its impact on abstaining and light alcohol and cannabis use, related consequences, and key cognitive and behavioral outcomes in a two-arm RCT (N = 800) across the first semester and academic year. Aim 3 will assess early implementation outcomes using mixed methods, including focus groups with a Campus Advisory Board, validated survey measures, and intervention analytics, to inform future dissemination and implementation strategies.