Outcomes of Childhood Preventive Intervention Across 2 Generations: A Nonrandomized Controlled Trial.

Importance: Trials of preventive interventions for children that were implemented in the 1980s have reported sustained positive outcomes on behavioral and health outcomes into adulthood, years after the end of the intervention. This present study examines whether intervention in childhood may show sustained benefits across generations. Objective: To examine possible intervention outcomes on the offspring of individuals (now parents) who participated in the Raising Healthy Children preventive intervention as children in the elementary grades. Design, Setting, and Participants: This nonrandomized controlled trial was conducted in public elementary schools serving high-crime areas in Seattle, Washington. The panel originated in Seattle but was followed up locally and in out-of-state locations over time. Data analyzed in this study were collected from September 1980 to June 2011, with follow-up of the firstborn offspring (aged 1 through 22 years) of 182 parents who had been in the full intervention vs control conditions in childhood. Their children were assessed across 7 waves in 2 blocks (2002-2006 and 2009-2011). Data were analyzed for this article from September 2018 through January 2019. Interventions: In grades 1 through 6, the Raising Healthy Children intervention provided elementary school teachers with methods of classroom management and instruction, first-generation (G1) parents with skills to promote opportunities for children's active involvement in the classroom and family, and second-generation (G2) child with social and emotional skills training. Main Outcomes and Measures: Outcomes examined in the third-generation (G3) offspring were self-regulation (emotion, attention, and behavioral regulation), cognitive capabilities, and social capabilities. Risk behaviors, including substance use and delinquency, were examined from age 6 years to study completion. Early onset of sexual activity was examined from age 13 years to study completion. Intent-to-treat analyses controlled for potential confounding factors. Results: A total of 182 G3 children were included in this analysis (72 in the full intervention and 110 in the control condition; mean age at first wave of data collection, 7 [range, 1-13] years). Significant differences in the offspring of intervention parents were observed across 4 domains: improved early child developmental functioning (ages 1-5 years; significant standardized β range, 0.45-0.56), lower teacher-rated behavioral problems (ages 6-18 years; significant standardized β range, -0.39 to -0.46), higher teacher-rated academic skills and performance (ages 6-18 years; significant standardized β range, 0.34-0.49), and lower child-reported risk behavior (ages 6-18 years; odds ratio for any drug use [alcohol, cigarettes, or marijuana], 0.27 [95% CI, 0.10-0.73]). Conclusions and Relevance: To our knowledge, this is the first study to report significant intervention differences in the offspring of participants in a universal childhood preventive intervention. Cost-benefit analyses have examined the benefits of childhood intervention in the target generation. The present study suggests that additional benefits can be realized in the next generation as well. Trial Registration: ClinicalTrials.gov Identifier: NCT04075019.