Efficacy of a Brief Intervention to Reduce Substance Use and Human Immunodeficiency Virus Infection Risk Among Latino Youth.

Familias Unidas is an efficacious and effective family-based intervention for preventing and reducing substance use and unsafe sexual behaviors among Latino youth. To facilitate its dissemination, Familias Unidas was shortened from a 12-week intervention to a 6-week intervention and evaluated. We hypothesized that brief Familias Unidas would be efficacious in reducing substance use and unsafe sexual behaviors relative to a comparison condition.We randomized 160 ninth-grade Latino adolescents and their families to brief Familias Unidas or a community practice control condition. Adolescents were surveyed at baseline and 6, 12, and 24 months after baseline.At 24 months, youth randomized to brief Familias Unidas had a significantly lower sexual initiation rate (34.0%) relative to control (55.0%), p = .02. Brief Familias Unidas also increased positive parenting. Moderation analyses revealed that brief Familias Unidas was significantly associated with decreased substance use initiation among girls (30.4% vs. 64.0%, respectively; p = .02), but not boys (28.0% vs. 26.7%, respectively; p = .91). Brief Familias Unidas was also significantly associated with reduced unsafe sex among adolescents aged 15 years or less (p < .001), but not among older adolescents (p = .37). Moderating effects were also found for family-level variables.Brief Familias Unidas was efficacious in reducing sex initiation and improving positive parenting. Moderation analyses suggested that brief Familias Unidas was efficacious in reducing substance use initiation and unsafe sex for certain Hispanic adolescent subgroups, highlighting the importance of conducting moderation analyses, and of targeting interventions for specific subgroups.