Psychometric validation of the French version of the Moral Injury Outcome Scale (MIOS).

OBJECTIVE: Moral injury is defined as the profound psychological, emotional, spiritual, and existential distress that arises from exposure to potentially morally injurious events-situations that violate deeply held moral beliefs and expectations. The Moral Injury Outcome Scale (MIOS) has emerged as a robust tool for assessing moral injury. The MIOS, initially validated in English-speaking military populations, was recently adapted into a 14-item French version. METHOD: This version was evaluated in a sample of 390 French-speaking Canadian Armed Forces personnel. To assess measurement invariance, the MIOS was further tested in a comparative sample of 490 English-speaking Canadian Armed Forces personnel deployed on the same operation. RESULTS: The French version of the MIOS showed strong psychometric properties with strong internal consistency reliability, factorial validity, and convergent validity. The proposed two-factor structure was consistent with the MIOS English version, and measurement invariance testing confirmed that the French and English versions of the MIOS satisfied configural, metric, and scalar invariance within military personnel. CONCLUSION: Overall, the French version of the MIOS is a valid and reliable measure, enabling robust assessment of moral injury among French-speaking populations and broadening its applicability in research and clinical settings. (PsycInfo Database Record (c) 2026 APA, all rights reserved).