Long-Term Effect of a Bystander Violence Intervention on Prevalence of Drug Use Disorders in a Prospective Cohort of Emerging Adults

Introduction

Bystander interventions have shown promise to reduce interpersonal violence. Substance use may co-occur with violence; thus, bystander training to identify and intervene in these ‘risky’ situations may additionally reduce substance abuse.

Design

Prospective cohort study based on an existing (2010–2014) cluster-randomized controlled trial (RCT) evaluating Green Dot bystander intervention efficacy.

Setting/Participants

Kentucky high school seniors (n = 3377) from intervention and control high schools were recruited in three waves to begin cohort surveys during the spring of 2014–2016 and followed from high school into adulthood through 2018.

Intervention

Green Dot bystander training in school as randomized (2010–2014) and reported after high school (2014–2018).

Main outcome measure

Substance use disorder (SUD, DSM-5 criteria) rates (%) for the past 12 months at baseline (5.1%), 12-month follow up (4.7%), and final follow up (12–48 month; 6.8%) follow up.

Results

No statistically significant differences were observed between intervention and control schools at either follow up. However, self-reported receipt of Green Dot bystander training in and after high school was associated with lower substance use disorder (SUD) rates at the 12-months (n = 2078; p = .004) and final follow-up (at 24–48 month; n = 1896; p = .001) relative to those receiving no training. This pattern held for both sexes and among those attending 4-year colleges.

Conclusions

Receipt of Green Dot bystander training, in and after high school, may additionally reduce SUD rates. Replication research using prospective cohorts and other bystander training approaches is encouraged.