Incident commander decision making: Quantitative evaluation of instantaneous and considered decisions.

The Incident Commander (IC) decision-making process has previously been modeled primarily by qualitative evaluation methods, which has made it difficult to generalize an objective model. In this study, we took a quantitative approach to elucidate a decision-making model based on the "dual-process" model that consists of instantaneous decisions ("System 1") and considered decisions ("System 2") to gain new insights regarding the IC decision-making process. High-fidelity simulation data from eight mass-casualty incidents (MCIs) were analyzed in two categories. The first category represents cues of new information and the IC's actions, divided into three main subcategories: actions following the MCI protocol, responses following cues, and actions without a cue. The second category divides the simulation into three MCI management phases: (1) evaluation and triage, (2) treatment and preparedness for evacuation, and (3) evacuation. Actions that followed the MCI protocol were significantly higher in the first phase compared to the other two phases (p<0.01 for both phases). Responses following cues were significantly higher in the second phase compared to the first (p<0.01). Actions without a cue were significantly higher in both the second and third phases compared to the first (p<0.01 for both phases). The results reveal that the IC followed MCI protocol guidance in the simulation initiation and immediately responded to cues, which fits "System 1". As the simulation evolved, the IC made more planned tasks and initiated actions without leading cues, which fits "System 2". The study found that ICs can change their decision-making mode, and this understanding can serve to improve their decision-making process and increase casualty survival rates.