Group Motivational Interviewing for Adolescents: Change Talk and Alcohol and Marijuana Outcomes

Objective: Little is known about what may distinguish effective and ineffective group interventions. Group motivational interviewing (MI) is a promising intervention for adolescent alcohol and other drug use; however, the mechanisms of change for group MI are unknown. One potential mechanism is change talk, which is client speech arguing for change. The present study describes the group process in adolescent group MI and effects of group-level change talk on individual alcohol and marijuana outcomes. Method: We analyzed 129 group session audio recordings from a randomized clinical trial of adolescent group MI. Sequential coding was performed with the Motivational Interviewing Skill Code (MISC) and the CASAA Application for Coding Treatment Interactions software application. Outcomes included past-month intentions, frequency, and consequences of alcohol and marijuana use; motivation to change; and positive expectancies. Results: Sequential analysis indicated that facilitator open-ended questions and reflections of change talk increased group change talk. Group change talk was then followed by more change talk. Multilevel models accounting for rolling group enrollment revealed group change talk was associated with decreased alcohol intentions, alcohol use, and heavy drinking 3 months later; group sustain talk was associated with decreased motivation to change, increased intentions to use marijuana, and increased positive alcohol and marijuana expectancies. Conclusions: Facilitator speech and peer responses each had effects on change and sustain talk in the group setting, which were then associated with individual changes. Selective reflection of change talk in adolescent group MI is suggested as a strategy to manage group dynamics and increase behavioral change.