Major Findings #6

Communities With More Opportunities For Participation In Prevention Positively Impact Substance Use By Youth

Since the National Cross-Site Evaluation was studying youth in actual community settings, some of the youth in comparison groups would have the opportunity to enter prevention programs other than the CSAP program under study. In order to identify the degree to which this occurred, and the effects on study findings, data were gathered on the availability of prevention programming in the school and community environments of study youth. When study communities were divided into those that offered higher and lower opportunity for participation in prevention programs, an important finding emerged. Comparison youth in communities that offered more prevention services reported significantly lower rates of substance use relative to comparison youth in communities that offered fewer prevention opportunities.

Average Change in Substance Use From Program Entry to Exit for Comparison Group Youth: Sites With Low and High Opportunity for Comparison Group Prevention Participation (n = 4,341)

These findings have important implications.

• The results indicate that comparison youth in sites with high opportunity for prevention participation have lower rates of use than youth in sites with fewer available prevention resources. This supports the Cross-Site Evaluation conclusion that “Prevention Works” for high-risk youth.



• The results indicate that prevention effects in sites with higher availability of prevention services will be underestimated because comparison youth in these field settings also benefit from prevention. To make sure the findings of the study are accurate, estimates of the magnitude of prevention effects on youth are made using the 23 sites in which comparison youth had lower opportunity to participate in prevention programs.

This finding also suggests that prevention effectiveness is often underestimated in evaluation studies in which comparison youth have opportunities to participate in prevention activities within the community.