Non-suicidal self-injury motivation scale in a community sample of adolescents: a methodological study

The prevalence of non-suicidal self-injury among South Korean adolescents has increased significantly, requiring academic attention. This methodological study aims to develop a non-suicidal self-injury motivation scale for adolescents and evaluate its validity and reliability.

In the first phase of scale development, the factors constituting self-injury motivation were identified through a literature review and analysis of online counseling data from self-injuring adolescents. In the second phase, 45 initial preliminary items were derived based on the identified factors, and 38 preliminary items were selected through content validation by experts. In the scale validation phase, the survey was conducted using 38 items. Data were collected from adolescents with a history of self-injury, using exploratory factor analysis (EFA) involving 715 participants and confirmatory factor analysis (CFA) involving 537 participants. The EFA involved 27.0% male and 73.0% female participants, with a mean age of 16.83 years, and the CFA involved 20.7% male and 79.3% female participants, with a mean age of 16.15 years. The data collected were tested for validity and reliability using SPSS 28.0 and M-plus.

The EFA yielded four factors and 24 items. The factors were named interpersonal influence, emotion regulation, sensation seeking, and anti-suicide, and the scale had an explanatory power of 55.8%. In the CFA, the fit of the 23-item model after deleting one item with low standardized factor loadings was x² = 1081.52 (p < .001), CFI = 0.829, RMSEA = 0.084, and SRMR = 0.075, confirming the acceptability of the self-injury motivation scale for adolescents. The scale evaluation results for convergent validity and discriminant validity met the criteria. The reliability test results showed that the overall reliability (Cronbach's α) was 0.88, and the reliability (Cronbach's α) of each factor was 0.89 for interpersonal influence, 0.83 for emotion regulation, 0.63 for sensation seeking, and 0.80 for anti-suicide, satisfying internal consistency.

In this study, the self-injury motivation scale for adolescents in the community comprised four factors and 23 items. The scale can be used to examine self-injury motivation among adolescents in the community and to develop self-injury prevention intervention programs.