Development and Validation of the Korean Version of the Multidimensional Non-Suicidal Self-Injury Scar Scale

Abstract

Objective Non-Suicidal Self-Injury (NSSI) scars are common in individuals with NSSI experiences. However, little is known about NSSI scars because related tools are limited. This study aimed to develop and validate the Korean version of the multidimensional Non-Suicidal Self-Injury Scar Scale (K-NSSI-ScarS), consisting of three components: NSSI scar measurement, NSSI scar cognition, and NSSI scar concealment.Methods A total of 333 Korean adults with at least one NSSI scar and history of NSSI within the last 5 years (age: 18 to 39 years) completed the online survey. We conducted exploratory (n=133) and confirmatory (n=200) factor analyses of NSSI scar cognition. To measure the internal consistency of each subfactor of the scar cognition and scar concealment components, we used Cronbach’s α. Kappa and intraclass correlation coefficients were used to measure the test-retest reliability of the entire scale. We also assessed the convergent and construct validity of the K-NSSI-ScarS.Results Factor analyses showed a 5-factor structure consisting of 23 items. Internal consistencies and test-retest reliability were excellent. The moderate correlation between the five subfactors of NSSI scar cognition and related concepts (e.g., acquired capability of suicide) confirmed the convergent validity. Lastly, moderate correlations were found between NSSI scar concealment, self-concealment, NSSI scar measurement information, and the five subfactors of NSSI scar cognition.Conclusion The results verify the psychometric properties and support the necessity of a multidimensional NSSI scar scale.