Developing a Smartphone-Based Adjunct Intervention to Reduce Cannabis Use Among Juvenile Justice-Involved Adolescents: Protocol for a Multiphase Study

Background: Adolescents involved in the juvenile justice system who use cannabis are at an increased risk of future substance use disorders and rearrest. Many court-involved, nonincarcerated (CINI) youth are referred for services in the community and often encounter multiple barriers to care, highlighting the need for minimally burdensome services that can be delivered in justice settings. Digital health interventions are accessible, easy to implement, and can provide ongoing support but have not been developed to address the unique needs of CINI youth who use cannabis. Objective: This multiphase study will aim to develop, implement, and pilot test a novel smartphone app, Teen Empowerment through Computerized Health (TECH), to reduce cannabis and other substance use among CINI youth. TECH is conceptualized as a digital adjunct to a brief computerized intervention delivered by our family court partner. Methods: Following the principles of user-centered design, phase I interviews with CINI youth aged 14-18 years (n=14-18), their caregivers (n=6-8), and behavioral health app developers (n=6-8) will guide the TECH design decisions. Next, in phase II, CINI youth (n=10) will beta test the lECH app prototype for 1 month; their feedback regarding feasibility and acceptability will directly inform the app refinement process. Finally, in phase III, CINI youth (n=60) will participate in a pilot randomized controlled trial for 6 months, comparing the preliminary effectiveness of the adjunctive lECH app on cannabis use outcomes. Results: Phase I data collection began in September 2020 and was completed in December 2021; 14 CINI youth, 8 caregivers, and 11 behavioral health app developers participated in the study. Phases II and III will occur in 2022 and 2023 and 2023 and 2025, respectively. Conclusions: This body of work will provide insight into the feasibility and acceptability of a smartphone-based adjunctive intervention designed for CINI youth. Phase III results will offer a preliminary indication of the effectiveness of the lECH app in reducing cannabis use among CINI youth.