Session: Evidence of Long-Term Prevention Impact in Three Landmark Studies: Findings from the Community Youth Development Study, Seattle Social Development Project and Ssdp Intergenerational Project (Society for Prevention Research 25th Annual Meeting)

Evidence that preventive interventions have long-term positive impact on health and development is instrumental to building public support and political will for investing in effective prevention at scale. This symposium showcases two preventive interventions implemented in childhood and adolescence that have demonstrated long-term impact in three rigorous longitudinal studies: Communities That Care and Raising Healthy Children. The chair will briefly explain the context and motivation for developing each intervention, the theory of change, the essential role of high-quality implementation for achieving sustained impact, and how challenges to robust longitudinal evaluation were overcome.

The first paper discusses Communities That Care (CTC), a science-based community prevention planning and capacity building system designed to prevent behavioral health problems among youth community-wide and evaluated in a community-randomized trial, the Community Youth Development Study, involving 24 communities from 7 states. Over a 5-year period, experimental communities were trained and offered ongoing technical assistance to sustain high quality implementation of CTC and evidence-based prevention programs for youth in grades 5 through 9. Evidence of CTC’s long-term impact on substance use, antisocial behavior, and violence into young adulthood will be shared.

The second paper discusses the Seattle Social Development Project (SSDP), in which a 3-component preventive intervention called Raising Healthy Children (RHC) was implemented in Seattle public schools over six years when target children were in grades 1 to 6 to improve the skills of teachers, parents, and children themselves. The overall goal was to increase positive functioning and decrease problems related to delinquency, substance use, mental health, and risky sexual behavior. SSDP was evaluated in a longitudinal cohort of 808 interviewed 15 times from ages 10 to 39. SSDP’s consistent pattern of improved outcomes into middle adulthood for the group who received RHC will be featured.

SSDP’s Intergenerational Project evaluated whether intervention effects extended to the children of those who had received the RHC intervention in the SSDP. The third paper describes next-generation impacts in the form of significantly higher academic skills and lower rates of developmental delays, teacher-rated externalizing behavior, and drug use initiation in children whose parents had received RHC compared to children of controls.

The discussant will comment on findings with an emphasis on two issues: Implications for the development of prevention approaches likely to show sustained impact, and the role of long-term efficacy evidence in supporting prevention investments at scale to achieve greater public health impact.