Feasibility of Immersive Virtual Reality for Assessing Mass-Casualty Triage Decision-Making in a NATO Civil–Military Emergency Management Exercise: A Cross-Sectional Study

BACKGROUND: Mass-casualty incident (MCI) triage is difficult to teach and assess under realistic operational conditions. Immersive virtual reality (VR) may provide a standardized and operationally relevant platform for evaluating triage decision-making and prioritization of immediate life-saving interventions during disaster preparedness exercises. OBJECTIVE: To evaluate performance in MCI triage and prioritization of immediate life-saving interventions using an immersive VR scenario embedded in a NATO civil-military emergency management exercise, while also describing participants' perceptions of usefulness, ease of use, immersion, and physical comfort. METHODS: This cross-sectional observational study was conducted during the NATO Emergency Management Exercise "Bulgaria 2025" in Montana, Bulgaria. Civilian and military first responders who completed the immersive scenario and post-experience questionnaire were included. The VR assessment, delivered through Meta Quest 3 headsets and haptic vests, comprised 14 triage items and 2 immediate life-saving intervention items. The reference standard for triage categorization was based on the Simple Triage and Rapid Treatment (START) algorithm. The primary outcome was item-level accuracy. Secondary outcomes included perceived usefulness, ease of use, immersion, physical comfort, and perceived contribution of haptic feedback. RESULTS: A total of 102 valid post-simulation questionnaires were analyzed. Participants had a mean age of 34.3 years (SD 8.8), were predominantly male (98.0%), mainly military-affiliated (86.3%), and had a median of 10 years of professional experience. Triage performance was heterogeneous: accuracy exceeded 75% in several core items. Perceived usefulness and ease of use were high, with composite medians of 7.0 (IQR 6.0-7.0) and 7.0 (IQR 6.5-7.0), respectively. Presence/immersion was also high (median 6.25, IQR 5.5-7.0), and discomfort was low (median 1.0, IQR 1.0-2.0). CONCLUSIONS: In a NATO civil-military emergency management exercise, immersive VR was highly acceptable, usable, and well tolerated, while revealing substantial item-level variability in MCI triage decisions and immediate life-saving intervention choices. These findings suggest that immersive VR may offer a feasible and operationally relevant platform for standardized assessment of disaster triage performance and for identifying specific decision bottlenecks relevant to preparedness and interoperability.