Subgroups of self-injury and suicidal behavior among adolescents: A latent class analysis

This cross-sectional study examined functionally and developmentally heterogeneous groups of adolescents based on self-injurious and suicidal behaviors using latent class analysis. Drawing on a nationally stratified sample of 5,937 South Korean students in Grades 4–12, this study identified four profiles: (1) a nonsuicidal self-injury group (5%), (2) a high-risk self-harm group (8%) with high suicidality, (3) a low-risk group (78%), and (4) a moderate-risk self-harm group (9%) with low suicidality. These groups differed in psychosocial predictors and developmental distributions. The high-risk group, which was predominantly female, had greater trauma exposure and higher levels of depression, and they were reluctant to discuss their emotional issues. The moderate-risk group exhibited impulsive self-harm, somatic symptoms, and low peer support. Those in the nonsuicidal self-injury group showed frequent physical complaints but few signs of suicidal thoughts or trauma exposure, suggesting a more habitual pattern of self-injury. Preadolescents were more likely to be classified in the high- and moderate-risk groups, while nonsuicidal self-injury was more common during early adolescence. These results suggest that self-injurious behaviors take different forms depending on developmental stage and psychosocial functioning. These differences may inform age-appropriate approaches, especially in cultures where emotional distress is internalized or expressed somatically.