Delaying youth substance-use initiation: A cluster randomized controlled trial of complementary youth and parenting interventions

Objective: The parenting intervention Familias: Preparando la Nueva Generación (FPNG), was developed using community-based participatory research in primarily immigrant Latino communities. FPNG was designed to complement the efficacious classroom-based substance-use prevention program keepin’ it REAL (kiR). This study tests whether using FPNG in combination with kiR delays the initiation of alcohol and cigarette use over an 18-month period among a sample of predominantly Mexican-heritage 7th grade youth (N = 358, M age = 12 years) beyond the effects of the classroom intervention alone and control conditions. Method: In a completed cluster-randomized controlled trial, 9 schools were evenly randomized into 3 conditions: Parent and youth (n = 118 youth); youth-only (n = 136 youth), or control (n = 139 youth). All participants and facilitators were aware of group assignment and the receipt of an intervention. Logistic regression models using the maximum likelihood estimator assessed whether kiR (10 weeks) concurrently delivered with FPNG (8 weeks) delays substance use among 7th grade adolescents. Results: We found no significant effects by condition immediately following the intervention. However, at the 1 year post intervention follow up, compared with students who received kiR only, adolescents in the FPNG + kiR condition who had never tried alcohol or cigarettes at baseline were less likely to have tried either alcohol (odds ratio [OR] =.43, 95% CI [.21,.88], p <.05) or cigarettes (OR =.39, 95% CI [.19,.84], p <.05). Conclusions: Engaging primarily monolingual Spanish-speaking parents in a parenting intervention boosts the effects of a school-based youth intervention in delaying substance-use initiation.