Optimizing an App-based Intervention for Emerging Adults to Reduce Cannabis and Alcohol Co-use - This K23 award will support Dr. Florimbio, a clinician-scientist with experience researching and treating substance use disorders, in becoming an independent researcher. Targeted research and training activities will extend her knowledge and develop her expertise in delivering technology-driven adaptive interventions (e.g., smartphone app) to reduce cannabis/alcohol co-use (i.e., using both substances within a single time period [e.g., past month], which could be during different occasions or simultaneously so drug effects overlap) among emerging adults (EAs; ages 18-25) whose behaviors differ from majority norms in settings (i.e., college) where interventions can be initiated. Training: Dr. Florimbio proposes a comprehensive training plan to (1) learn to identify components for co-use interventions for EA college students using user-informed methods, (2) acquire the essential skills and knowledge to use Sequential Multiple Assignment Randomized Trials (SMART) to optimize adaptive interventions, and (3) learn best practices for collection and analysis of intensive longitudinal data informing such interventions. Context: EAs who encounter greater challenges often experience additional stressors relative to those who do not, which may explain, in part, why some EAs consume cannabis and alcohol at higher rates, have greater co-use, and experience more consequences. Emerging adulthood is a period where substance use reaches peak prevalence and responsibilities are shifting. This period, for about half of EAs, coincides with attending college, a setting that connotes substance use and availability. Efficacious interventions to reduce cannabis/alcohol co-use for EA college students are lacking, with the college period being an ideal time to address co-use and deliver early interventions. Optimization of interventions to address variations in needs based on individual factors and substance use severity is also a crucial next step for parsimonious delivery of interventions, with some individuals needing a greater intervention dose or an extended dose over time. The overall research objective is to develop and test an app-based adaptive intervention for EA college students to reduce cannabis/alcohol co-use. Research Plan: The research aims include: Aim 1 which is to develop app-based intervention content with iterative refinement of intervention components and end-user testing (4 rounds, n=5 per round). Based on Aim 1 findings, Aim 2 is to conduct a non-restricted pilot SMART with EA college students from multiple campuses to assess feasibility and acceptability of the intervention components. Aim 2 will inform a full-scale SMART (R01 submission) to optimize technology-driven interventions to reduce co-use among EA college students. Innovations include state-of-the-art training, co-use intervention development, and the SMART design. Optimization of adaptive interventions for EAs to reduce cannabis/alcohol co-use is an important next step and will have high impact on substance use trajectories and health.
