Challenge and opportunity in evaluating a diffusion-based active bystanding prevention program: Green Dot in high schools.

Increasing attention has recently been paid to the development of prevention programs designed to actively engage bystanders in prevention efforts to reduce the risk of sexual and dating violence; yet, few evaluations have been conducted. Our proposed plan to rigorously evaluate a randomized intervention trial of the Green Dot bystander program as it is implemented in high schools across Kentucky is presented. We highlight the value of measuring violence victimization and perpetration outcomes, capturing actual and observed student bystander behaviors, and testing the diffusion of Green Dot training through students' social networks.