RESUMEN
OBJECTIVE: This randomized controlled trial is the 1st study to evaluate the additive efficacy of mindfulness meditation to brief school-based universal cognitive behavior therapy (CBT + MM) for adolescent alcohol consumption. Previous studies have lacked strong controls for nonspecific effects, and treatment mechanisms remain unclear. The present study compared a CBT + MM condition to an active control CBT intervention with progressive muscle relaxation (CBT + PMR) for nonspecific effects and an assessment-only control (AoC). METHOD: Cluster sampling was used to recruit Australian adolescents (N = 404; 62% female) ages 13-17 years (M = 14.99, SD = .66) of mostly Australian-New Zealand or European descent. School classes were randomized to 3 intervention conditions (CBT + PMR = 8 classes, CBT + MM = 7 classes, AoC = 7 classes), and adolescents completed preintervention, postintervention, and 3- and 6-month follow-up assessments, including measures of alcohol consumption, mindfulness, impulsivity, and the alcohol-related cognitions of alcohol expectancies and drinking refusal self-efficacy. RESULTS: Multilevel modeling analyses revealed that both intervention conditions reduced the growth of alcohol consumption compared to the AoC (b = -.18, p = .014), although CBT + MM was no more effective than was CBT + PMR (b = -.06, p = .484). Negative alcohol expectancies increased for adolescents in the intervention conditions compared to the AoC (b = 1.09, p = .012), as did positive alcohol expectancies (b = 1.30, p = .008). There was no effect of interventions on mindfulness, drinking refusal self-efficacy, or impulsivity. CONCLUSIONS: There was no evidence of mindfulness-specific effects beyond existing effects of CBT within a brief universal school-based CBT intervention. Hypothesized mechanisms of change were largely unsupported. (PsycINFO Database Record (c) 2019 APA, all rights reserved).