Abstract
Non-suicidal self-injury (NSSI) affects 15-20% of adolescents-disproportionately girls-and is a strong predictor of eventual suicide attempts and suicide. Many girls now initiate NSSI before age 10. These early-starters exhibit greater frequency of NSSI, use more diverse methods, and are hospitalized more often, yet there are no empirically supported prevention programs for preadolescents. Obstacles to prevention include ascertaining who is sufficiently vulnerable and specifying mechanistic intervention targets. Recent research indicates that (1) preadolescent girls with ADHD who are also maltreated are at alarming risk for NSSI and suicide attempts by adolescence, and (2) the conjoint effects of these vulnerabilities are sufficiently potent for targeted prevention. Research also indicates that existing interventions are effective in altering child- and family-level mechanisms of NSSI. These interventions alter neurobiological markers of vulnerability, which can be used as proximal efficacy signals of prevention response, without waiting for NSSI and suicide attempts to emerge.