Non-suicidal self-injury is associated with psychotic like experiences, depression, and bullying in Korean adolescents.

Aim Non-suicidal self-injury (NSSI) is common among adolescents, and several different factors can affect its prevalence. The present study examined the associated characteristics predicting NSSI among adolescents in South Korea. Methods In total, 1674 high school students were recruited for a cross-sectional survey. They completed self-reported assessments, including the Deliberate Self-Harm Inventory (DSHI), the Center for Epidemiological Studies Depression Scale (CESD), the State-Trait Anxiety Inventory for Children (STAIC), and the Prodromal Questionnaire-16 (PQ-16), as well as their bullying experience. The NSSI group was defined as the sample group with at least one NSSI behaviour on the DSHI scale. A logistic regression analysis was performed using the NSSI group as the dependent variable. Results The prevalence of NSSI was 28.3% (boys, 30.4%; girls, 24.4%) among adolescents. The most common type of NSSI behaviour among adolescents was interference with wound healing and sex differences in the method were examined. The CES-D, STAIC-trait, and PQ-16 scores were significantly higher and the RSES score was significantly lower in the NSSI group than those in the non-NSSI group. Participants' experience with bullying, such as being victims, bullies, bully-victims, and witness to bullying, were more likely to be in the NSSI group. In a logistic regression analysis, NSSI was significantly associated with male sex, low academic achievement, higher depression, psychotic-like experiences, being bullied, and witnessing bullying. Conclusion The results of this study suggest the need to identify and manage related psychologic factors in adolescents with NSSI, including psychotic-like symptoms.