Real-Time Readiness to Quit and Peer Smoking within a Text Message Intervention for Adolescent Smokers: Modeling Mechanisms of Change.

The psychological construct, readiness to change, is established as a central construct within behavioral change theories such as motivational interviewing (MI). Less is known about the interplay of mechanisms for change within adolescent treatment populations. Understanding the timing and interactive influence that adolescents' readiness to stop smoking and peer smoking have on subsequent tobacco use is important to advance intervention research. Toward this end, we used ecological momentary assessment (EMA) data from an automated texting smoking intervention randomized controlled trial to model the interactive effects of readiness to stop smoking and friends smoking on adolescent tobacco use. Two hundred adolescents were randomized into experimental treatment or attention control conditions, provided smart phones, and were followed for 6 months. African American youth represented the majority of the sample. We collected monthly EMA data for 6 months on friends smoking and readiness to stop smoking as well as survey outcome data. We tested a moderated mediation model using bias corrected bootstrapping to determine if the indirect effect of treatment on cigarettes smoked through readiness to stop smoking was moderated by friends smoking. Findings revealed that readiness to stop smoking mediated the effects of treatment on cigarettes smoked for those adolescents with fewer friends smoking, but not for those with more friends smoking. These results support importance of peer-focused interventions with urban adolescents and provide target mechanisms for future research.