Emergency departments under fire: analysing the impact of heat on waiting time.

This study examines whether extreme perceived temperature is statistically associated with emergency department (ED) waiting times. While prior research has documented demand-side effects of heat through increased patient inflow, we explore whether high-temperature conditions are also associated with operational performance indicators within EDs. We examine whether extreme perceived temperature is associated with waiting times, conditional on inflow and fixed effects. Recognizing the critical need to prevent excessive delays in EDs, the study uses individual-level data and hourly climate data to empirically analyze ED waiting times in the Campania region of Italy during every summer from 2016 to 2020. Our analysis, conducted through Feasible-Generalized Least Squares estimators, reveals that perceived temperatures exceeding 39 °C for six hours, 41° for three, and 44° for any amount of time, are statistically associated with longer waiting times, including when controlling for patient inflow. These findings offer insights that can enhance local public health strategies and improve emergency preparedness, and help to assess the cost of extreme heat events.