Assessing Efficiency in a Static-Based 9-1-1 Ambulance Service: An Analysis of Operational Performance Metrics

Abstract

Objectives: This study sought to evaluate performance indicators to assist a static-based 9-1-1 agency in defining its response efficiency. Methods: Initial assessment of three metrics—unit hour utilization (UHU), fractile response intervals, and level 0 frequency (occurrence when no ambulances are available to respond)—suggested the agency’s response over its four coverage zones was inefficient, so an operational change was implemented: an ambulance was relocated from one service area to another to improve the overall response productivity. A 2-year retrospective analysis was performed to determine the impact ambulance relocation had on the three targeted measurements. Results: The operational change resulted in a statistically significant change in unit hour utilization, a non-significant increase in fractile response intervals, and a statistically significant reduction in level 0 frequency from pre- to post-operational change times. Conclusions: These findings suggest a way to evaluate the efficiency of static-based ambulance deployment and potentially identify strategies for redeployment.