Elementary schools can be effective sites for universal preventive interventions. Less is known about how long effects of intervention in elementary grades last. Can they improve outcomes in adulthood? To test effects of a social developmental intervention in the elementary grades on adult life through the 30s, the Seattle Social Development Project, a nonrandomized controlled trial, followed all consenting 5th-grade students (N = 808) from 18 Seattle public elementary schools from age 10 (in 1985) to age 39 (in 2014), with 88% retention. The sample was gender balanced and ethnically and economically diverse. The full intervention, called Raising Healthy Children, continued from Grades 1 through 6 and consisted of teacher in-service training in classroom management and instructional methods; cognitive, social, and refusal skills training for children; and parent workshops in child behavior monitoring and management, academic support, and anticipatory guidance. Using structural equation modeling, we examined intervention effects from age 30 to age 39 across 9 constructs indicating 3 domains of adult life: health behavior, positive functioning, and adult health and success. An omnibus test across all 9 constructs indicated a significant positive overall intervention-control difference. Examined individually, significant intervention effects included better health maintenance behavior, mental health, and overall adult health and success. Significant effects were not found on substance use disorder symptoms, sex-risk behaviors, or healthy close relationships in the 30s. Results indicate that sustained, theory-based, multicomponent intervention in the elementary grades can produce lasting changes in health maintenance, mental health, and adult functioning through the 30s.
Keywords: Adult functioning; Adult health; Childhood intervention; Elementary school; Mental health; Raising Healthy Children; Social development.