Understanding Adolescent Non-Suicidal Self-Injury: A Narrative Review of Theoretical Models and Evidence-Based Psychotherapies.

OBJECTIVES

Adolescent non-suicidal self-injury (NSSI) is a marker of severe emotional distress and a significant public health concern. This narrative review aimed to synthesize major theoretical models explaining the psychopathology of NSSI and critically evaluate the efficacy of evidence-based psychotherapies using the most recent high-level evidence.

METHODS

We searched articles in major academic databases published from January 2000 up to June 2025. We prioritized studies on adolescents, including efficacy studies (randomized controlled trials and meta-analyses) addressing NSSI as a primary outcome, and key theoretical papers.

RESULTS

NSSI was understood through integrated models, prominently featuring emotion dysregulation (biosocial theory), experiential avoidance (cognitive-behavioral models), impaired mentalization (attachment theory), and operant conditioning (functional model). The synthesis of high-level evidence, including a 2021 review from Cochrane, indicated that dialectical behavior therapy (DBT) had the strongest empirical support (high-certainty evidence) for reducing adolescent NSSI. However, while mentalization-based treatment, acceptance and commitment therapy, and attachment-based family therapy offered promising mechanism-specific approaches, evidence for their effectiveness for NSSI was preliminary or uncertain.

CONCLUSION

DBT is currently the first-line treatment for NSSIs in adolescents. However, the field must move toward personalized care. Future research should focus on validating alternative therapies through head-to-head randomized controlled trials, identifying the core change mechanisms across treatments, and implementing stepwise care models to improve accessibility.