Randomized effectiveness trial of a parent and youth combined intervention on the substance use norms of Latino middle school students

This article advances knowledge about the effectiveness of applying a community-based efficacious parenting intervention in parallel with an efficacious preadolescent intervention in changing substance abuse norms among preadolescent Latino youth. The study employed a longitudinal, randomized control group design comparing three groups: (1) Parent intervention combined with a Youth intervention: Parent/Youth; (2) Parent intervention without a Youth intervention: Parent Only; and (3) Treatment as usual: Comparison. In the comparison group, parents participated in a standard parenting program delivered by the community partner, and the youth received the usual drug use prevention programming offered in their schools. Data from both parents and youth at the 19 participating schools were collected at pre-test, immediate post-test (4 months after pre-test), and two follow-up (8 & 20 months after the pre-test). The total sample includes 532 families (parent-child dyads). The parent-child dyads consisted of one parent and one youth ages 12-14. The retention rates for both parents and preadolescent were high across the different waves of data collection (79%-96%). Regression results of youth substance use norms were calculated based on three permutations of data: (a) original data, with no imputation and no propensity score matching; (b) imputed data but no propensity score matching; and (c) imputed data plus propensity score matching. Compared to the Comparison group, the Parent/Youth condition was the most effective in changing youth's norms, closely followed by the Parent Only condition. These findings make a significant contribution in advancing knowledge on family/youth substance use prevention for Latinos in a community environment. Although the study took place in a specific urban center in the Southwest US, its findings can be generalized to other urban communities of similar characteristics across the country.