204485 Emergency Response and the Built Environment: Does Urban Sprawl Delay Ambulance Arrival?

Monday, November 9, 2009

Matthew J. Trowbridge, MD, MPH , Department of Emergency Medicine, University of Virginia, Charlottesville, VA
Matthew Gurka, PhD , Department of Public Health Sciences, West Virginia University, Charlottesville, VA
Robert O'Connor, MD, MPH , Department of Emergency Medicine, University of Virginia, Charlottesville, VA
Objective: Minimizing emergency medical service (EMS) response time is an essential objective of prehospital care; yet the potential influence of the built environment on system performance is often not considered. In this study, we measured the association between urban sprawl and EMS response time to test the hypothesis that features of sprawling development increase the probability of delayed ambulance arrival.

Methods: EMS response times for 43,254 motor vehicle crashes were obtained from the 2000-2002 Fatal Analysis Reporting System; a national census of crashes involving ≥1 fatality. Sprawl at each crash location was measured using a continuous county-level index previously developed by Ewing et al. The association between sprawl and probability of a ‘delayed' EMS response (≥ 8 minutes) was then calculated using generalized linear mixed modeling to account for correlation among crashes from the same county.

Results: Urban sprawl is significantly associated with an increased probability of delayed EMS response (p = 0.03). This probability increases quadratically as the severity of sprawl increases while controlling for nighttime crash occurrence, road conditions, and presence of construction. For example, in sprawling counties (e.g. Fayette County, GA) the probability of a delayed EMS response for daytime crashes in dry conditions without construction was 69% (95% CI = 66%, 72%) compared with 31% (95% CI = 28%, 35%) in counties with smart-growth characteristics (e.g. Delaware County, PA).

Conclusions: Urban sprawl is significantly associated with increased EMS response time. This suggests that promotion of community design more consistent with smart-growth principles may improve EMS performance.

Learning Objectives:
To analyze the relationship between urban sprawl and emergency medical service (EMS) response time in the United States

Keywords: EMS/Trauma, Environment

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I am an assistant professor in the Department of Emergency Medicine at the University of Virginia. As an academic physician and epidemiologist, my current research is focused on the role of urban planning and community design in the prevention of traffic injuries and improved prehospital emergency care. Specific interests include the impact of urban sprawl on teen & elderly driver safety/mobility as well as the provision of emergency medical services in suburban areas. My previous publications in this area include analyses of sprawl's relationship to teen driving exposure and age of teen licensure.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.