PROSPER community-university partnership delivery system effects on substance misuse through 6 1/2Â years past baseline from a cluster randomized controlled intervention trial

► We examine long-term effects of PROSPER, an evidence-based prevention system. ► We measure lifetime, current, and frequency of misuse for a range of substances. ► PROSPER reduced substance misuse; rates were up to 31.4% lower than the control. ► There were greater intervention benefits for higher- versus lower-risk youth. ► Partnership-based delivery systems have potential for public health impact.