How Does the Public Perceive the Functions of Non-Suicidal Self-Injury? An Analysis by Gender and Age Group

Non-suicidal self-injury (NSSI) is a prevalent phenomenon among adolescents and poses significant public health concerns. Research has identified various functions of NSSI. However, public perceptions of these functions remain unclear. This cross-sectional study explored public understanding of the functions of NSSI and examined the relations between these perceptions and demographic factors of gender and age group. A nationwide online survey was conducted with 2000 Japanese adults (mean age 44.6 years, SD = 14.3) to assess their agreement with 20 statements about NSSI functions using a six-point scale. After conducting an exploratory factor analysis of the functions of NSSI, the study performed a two-factor analysis of variance with the factor scores for each function as the dependent variable and gender and age group as the independent variables. The exploratory factor analysis revealed a four-factor structure: (1) negative emotion regulation, (2) interpersonal effect, (3) avoidance of obligations, and (4) positive mood improvement. A series of two-way analyses of variance revealed gender and age differences, with women and younger individuals being more likely to endorse emotion regulation functions, and middle-aged and older adults more likely to support avoidance functions. Regarding interpersonal relationship factors, no statistically significant results were observed for either gender or age group. The findings suggest the importance of understanding public perceptions of NSSI functions for targeted psychological education and awareness. Future research should directly compare public perceptions with the perceptions of those who engaged in NSSI, considering other demographic factors.