Non-suicidal self-injury in adolescents: Prevalence and associations with identity formation above and beyond depression

•Non-suicidal self-injury (NSSI) was highly prevalent in our adolescent sample.•NSSI was positively related to depression and identity confusion in adolescents.•NSSI was negatively related to identity synthesis in adolescents.•Identity confusion explained additional variance of NSSI above and beyond depression.

Non-suicidal self-injury (NSSI), a highly prevalent behaviour in adolescents, refers to the direct destruction of one’s body tissue without suicidal intent. Given that identity formation is an important developmental task during adolescence, we investigate whether (problems with) identity formation are related to NSSI above and beyond age, gender, and depression. We assessed 532 high school students by means of the Self-Harm Inventory, the Erikson Psychosocial Stage Inventory, and the Child Depression Inventory. Our findings indicated that 26.5% of adolescents engaged in at least one form of NSSI, with no significant difference between boys and girls. Correlational analysis showed that NSSI was negatively related to identity synthesis and positively related to depression and identity confusion. Finally, identity confusion was able to explain additional variance in the presence/absence of NSSI above and beyond depression, age, and gender. Given that NSSI may constitute a means to deal with identity confusion, therapists should take this developmental task into account when developing prevention and intervention programs.