Unraveling Non-Suicidal Self-Injury Functions Through Network Analysis and Revealing Their Triangular Relationship With Psychosocial Factors and Personality Traits.

BACKGROUND: Non-suicidal self-injury (NSSI) imposes a significant burden on adolescents, making it essential to understand its underlying functions to develop effective interventions. This study aims to investigate the NSSI functional network and clarify the "psychosocial factors-personality-behavior" chain to inform the development of interventions for NSSI. METHODS: A total of 265 psychiatric inpatients aged 16-25 years with NSSI participated in this cross-sectional study. Network analysis was used to examine relationships among NSSI functions, and mediation analysis explored the pathways from psychosocial factors and personality to these functions. RESULTS: Five stable NSSI functional communities were identified, including internal emotion regulation (IER), psychological pain avoidance (PPA), social influence (SI), suicide resistance (SR), and sensation seeking (SS). The core function of IER exhibited the highest centrality. Psychosocial factors, including health adjustment (βIER = 0.450, βPPA = 0.303, βSI = 0.322, βSS = 0.130), interpersonal stress (βIER = 0.228, βPPA = 0.196, βSI = 0.301), neuroticism (βIER = 0.205, βPPA = 0.165), childhood emotional mistreatment (βIER = 0.204, βPPA = 0.195), openness to experience (βSI = 0.146), conscientiousness (βSR = 0.066), and extraversion (βSR = -0.079) were significantly associated with various NSSI functions. Neuroticism mediated most of the pathways connecting psychosocial factors to NSSI functions such as IER, PPA, and SI. CONCLUSIONS: Internal emotion regulation was the central driver among five functions of NSSI. Neuroticism played a key mediating role in the link between psychosocial factors and NSSI functions. Tailored interventions targeting emotion regulation are essential.