Development and Validation of an Instrument to Measure Work-Related Stress among Rescue Workers in Traumatic Mass-Casualty Disasters.

Rescue workers are a population at high-risk for mental problems as they are exposed to work-related stress from confrontation with traumatic events when responding to a disaster. A reliable measure is needed to assess rescue workers' work-related stress from their surveillance of a disaster scene to help prevent severe PTSD and depressive symptoms. The purpose of this study was to develop and validate the Work-Related Stress Scale (WRSS) designed to measure stress in rescue workers after responding to traumatic mass-casualty events. An exploratory sequential mixed methods procedure was employed. The qualitative phase of the item generation component involved in-depth interviews of 7 experienced rescue workers from multiple specialties who had taken part in 1 or 2 mass-casualty events: the 2018 Hualien earthquake or the 2016 Tainan earthquake. In the quantitative phase, a modified Delphi approach was used to achieve consensus ratings by the same 7 raters on the items and to assess content validity. Construct validity was determined by confirmatory factor analysis using a broader sample of 293 rescue workers who had taken part in 1 of 2 mass-casualty events: the 2018 Hualien earthquake or the 2021 Hualien train derailment. The final WRSS consists of 16 items total and 4 subscales: Physical Demands, Psychological Response, Environmental Interruption, and Leadership, with aggregated alphas of 0.74-0.88. The WRSS was found to have psychometric integrity as a measure of stress in rescue workers after responding to a disaster.