A Validation Study of the Korean Version of the Moral Injury Outcome Scale

Background: Moral injury (MI) refers to the psychological and functional consequences of potentially morally injurious events (PMIEs), involving perceived violations of deeply held moral beliefs. This study aimed to evaluate the reliability and validity of the Korean version of the Moral Injury Outcome Scale (K-MIOS) and to examine its applicability in Korean populations.Methods: A total of 546 Korean adults who had experienced at least one PMIE completed an online survey. The sample was randomly split into two groups (n=273 each) for exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Convergent and discriminant validity were assessed using correlation analyses with related psychological constructs. Signal detection analysis was performed to identify the optimal cutoff score indicating clinically significant and potentially targetable MI.Results: EFA and CFA supported a two-factor structure for the K-MIOS, with good internal consistency. The K-MIOS showed significant positive correlations with PMIE exposure, MI, post-traumatic cognitions and emotions, post-traumatic stress symptoms, general psychological distress, and psychosocial dysfunction, supporting its construct validity. Signal detection analysis identified a cutoff score of 27 as optimally efficient for identifying individuals with clinically significant MI.Conclusions: The K-MIOS showed robust psychometric properties and is suitable for assessing MI in Korean adults. This study provides initial evidence for a screening threshold, that may help identify individuals at clinical risk for MI.