The mediating effect of depressive symptoms on the relationship between bullying victimization and non-suicidal self-injury among adolescents: Findings from community and inpatient mental health settings in Ontario, Canada

Although bullying victimization has been linked to a number of behavioral and emotional problems among adolescents, few studies have investigate the mechanism through which bullying victimization affect non-suicidal self-injury. The objectives of this study were to examine the effect of bullying victimization on non-suicidal self-injury and the mediating effect of depressive symptoms on the relationship between bullying victimization and non-suicidal self-injury among adolescents. Data for this study came from the interRAI Child and Youth Mental Health dataset. A total of 1650 adolescents aged 12-18 years (M =14.56; SD =1.79; 54.2% males) were analyzed. Binary logistic and Poisson regression models were conducted to identify the mediating effect of depressive symptoms on the relationship between bullying victimization and non-suicidal self-injury. Of the 1650 adolescents studied, 611 representing 37% engaged in non-suicidal self-injury and 26.7% were victims of bullying. The effect of bullying victimization on non-suicidal self-injury was partially mediated by depressive symptoms after adjusting for the effect of demographic characteristics, history of childhood abuse, social support, and mental health diagnoses. The contribution of bullying victimization and depression to non-suicidal self-injury adds to the case for the development of trauma-focused interventions in reducing the risk of non-suicidal self-injury among adolescents.