Impact of the Garrett Lee Smith Youth suicide Prevention Program on suicide mortality.

We compared youth mortality rates across time between counties that implemented Garrett Lee Smith (GLS)-funded gatekeeper training sessions (the most frequently implemented suicide prevention strategy among grantees) and a set of matched counties in which no GLS-funded training occurred. A rich set of background characteristics, including pre-intervention mortality rates, was accounted for with a combination of propensity scoreÐbased techniques. We also analyzed closely related outcomes that we did not expect to be affected by GLS as control outcomes. Counties implementing GLS training had significantly lower suicide rates among the population aged 10 to 24 years the year after GLS training than similar counties that did not implement GLS training.