Using Implicit and Explicit Measures to Predict Nonsuicidal Self-Injury Among Adolescent Inpatients

Objective To examine the use of implicit and explicit measures to predict adolescent nonsuicidal self-injury (NSSI) before, during, and after inpatient hospitalization. Method Participants were 123 adolescent psychiatric inpatients who completed measures at hospital admission and discharge. The implicit measure (Self-Injury Implicit Association Test [SI-IAT]) and one of the explicit measures pertained to the NSSI method of cutting. Patients were interviewed at multiple time points at which they reported whether they had engaged in NSSI before their hospital stay, during their hospital stay, and within 3 months after discharge. Results At baseline, SI-IAT scores differentiated past-year self-injurers and noninjurers ( t121 = 4.02, p < .001, d = 0.73). These SI-IAT effects were stronger among patients who engaged in cutting (versus noncutting NSSI methods). Controlling for NSSI history and prospective risk factors, SI-IAT scores predicted patients’ subsequent cutting behavior during their hospital stay (odds ratio (OR) = 8.19, CI = 1.56–42.98, p < .05). Patients’ explicit self-report uniquely predicted hospital-based and postdischarge cutting, even after controlling for SI-IAT scores (ORs = 1.82–2.34, CIs = 1.25–3.87, p values