Rural and urban variation in mobile health substance use disorder treatment mechanisms and efficacy.

Residents of rural areas face significant barriers to substance use disorder (SUD) treatment, including poor access, stigma, lack of confidentiality, and distrust of mental health services, which may inhibit treatment engagement. Mobile health (mHealth) approaches offer personalized, private, and easily accessible SUD treatment for rural residents, but differences in treatment mechanisms and efficacy across rural and urban regions are unknown. The present study investigates rural versus urban differences in the efficacy an mHealth SUD treatment via the theorized treatment mechanisms: protective behavioral strategies, readiness to change, and peer network health. The study leverages the results of a randomized clinical trial of an mHealth SUD treatment called Peer Network Counseling-txt (PNC-txt) conducted among a sample of young adults (age 18-25) with cannabis use disorder (CUD). We hypothesize that the impact of PNC-txt treatment on the treatment mechanisms will be stronger in rural, as compared to urban, regions, consequently leading to significantly greater reductions in cannabis use among rural residents. Results indicate that while PNC-txt reduces past 30-day cannabis use at 6 months via 1-month increases in both protective behavioral strategies and readiness to change, these indirect effects of treatment do not differ significantly between rural and urban residents. Our findings suggest that readiness to change and protective behavioral strategies are effective treatment targets for reducing the frequency of young adult cannabis use and support mHealth as an important SUD treatment approach for addressing treatment barriers in rural regions.