Objective: To examine the long-term effects of a universal intervention in elementary schools in promoting positive functioning in school, work, and community, and preventing mental health problems, risky sexual behavior, substance misuse, and crime at ages 24 and 27 years.
Design: Nonrandomized controlled trial.
Setting: Fifteen public elementary schools serving diverse neighborhoods including high-crime neighborhoods in Seattle, Washington.
Participants: Sex-balanced and multiracial/multiethnic sample of 598 participants at ages 24 and 27 years (93% of the original sample in these conditions).
Interventions: Teacher training in classroom instruction and management, child social and emotional skill development, and parent workshops.
Main outcome measures: Self-reports of functioning in school, work, and community and of mental health, sexual behavior, substance use, and crime, and court records.
Results: A significant multivariate intervention effect across all 16 primary outcome indices was found. Specific effects included significantly better educational and economic attainment, mental health, and sexual health by age 27 years (all P < .05). Hypothesized effects on substance use and crime were not found at ages 24 or 27 years.
Conclusions: A universal intervention for urban elementary schoolchildren, which focused on classroom management and instruction, children's social competence, and parenting practices, positively affected mental health, sexual health, and educational and economic achievement 15 years after the intervention ended.