Measuring Occupational Moral Injury: Development, Validation and Applied Use of the Occupational Moral Injury Scale (OMIS)

Abstract

Moral injury is defined as the psychological, emotional, and spiritual suffering that can arise when an individual perpetrates, fails to prevent, or witnesses actions that transgress deeply held moral beliefs and expectations, or experiences betrayal by a trusted authority. Originating with military literature, moral injury is increasingly recognised in broader contexts, suggesting it is more widespread than initially thought. A key barrier to research in these broader contexts is the lack of valid, reliable measurement tools suitable for civilian use. This thesis addresses limitations in moral injury measurement beyond the military, first by evaluating military scales modified for civilian use, before constructing a novel scale designed for diverse occupational contexts. We present three chapters that expand moral injury measurement and understanding. In Chapter 2, two military moral injury scales were adapted and their psychometrics explored in a civilian sample: the Moral Injury Events Scale-Civilian (MIES-C) and Expressions of Moral Injury Scale-Civilian (EMIS-C). A sample of 280 civilians completed the scales along with additional measures of guilt, shame, anger, depression, PTSD, and anxiety. Confirmatory factor analyses (CFA) showed that the factor structure of both scales replicated well. Discriminant validity was supported by significant negative correlations with wellbeing. Both scales correlated as predicted with external validity criteria. Results suggest civilian populations are susceptible to moral injury, but existing measures may not capture this effectively, highlighting the need for further scale development. In Chapter 3, the Occupational Moral Injury Scale (OMIS) was developed to assess potentially morally injurious events (PMIEs) and primary moral injury markers (guilt, shame, anger, loss of trust, existential conflict) across occupational settings. Bifactor CFA (BCFA) and Item Response Theory (IRT) were used over two studies with 1,454 frontline health and first responder workers. Analyses revealed a bifactor structure of five PMIE factors (commission with agency, commission under duress, omission, witnessing, betrayal), and a general factor of moral injury. OMIS subscales demonstrated excellent internal consistency, convergent and divergent validity, with interesting differential relationships also observed among the subscales. Paper 2 established the OMIS as a validated tool for assessing moral injury risk in any occupation. In Chapter 4, the OMIS was established as measurement-invariant across specific occupations. Multigroup BCFA analyses were conducted with 1,431 participants from five high-risk occupational groups (health workers, emergency services, police, government officials, and teachers). Results demonstrated configural, metric, and scalar invariance of the OMIS across all groups and genders - indicating that items hold the same meaning across these groups and their scores can be compared. Unexpected differential findings were observed and discussed, with government officials reporting the highest moral injury symptoms but the lowest functional impairment. These results validate the OMIS for use across diverse groups, permitting direct comparisons in future research. Across the above chapters (four studies in total), we created a measure of occupational moral injury that reflects contemporary understanding and fills important gaps in moral injury measurement. The OMIS links morally injurious events to moral injury outcomes while remaining adaptable for use across settings without modification. Established measurement invariance also supports direct comparisons between high-risk groups, facilitating novel insights into how the construct presents in different settings. We hope the OMIS will contribute to further research into occupational moral injury, facilitating more focused interventions for treatment and prevention, and providing greater conceptual clarity in the field as a whole. Show more