Peer victimization and non-suicidal self-injury among depressed adolescents: a moderated mediation model

Non-suicidal self-injury (NSSI) among teenagers with depression is a major and pervasive issue. Previous studies have established peer victimization as a risk factor for non-suicidal self-injury. However, little is known about how it influences teenagers to harm themselves non-suicidally. A total of 740 depressive outpatients aged 12-18 years with non-suicidal self-injury were selected. General demographic information was collected using the self-designed scale, and relevant information was collected using the Functional Assessment of Self-Mutilation, the Patient Health Questionnaire-9, the Multidimensional Peer Victimization Scale, and the Borderline Personality Features Scale for Children. After controlling for age and sex, it was discovered that depressive symptoms partially mediated the association between peer victimization and non-suicidal self-injury (p < 0.001). The mediating influence of depressive symptoms was modulated by borderline personality features. Half of the mediating effect is the moderating influence (p = 0.002). The moderated mediation model constructed in this study reveals the internal mechanism between adolescent peer victimization and non-suicidal self-injury, which is of great significance for the prevention and intervention of adolescent non-suicidal self-injury.