It Could be Worse...It Could be Raining: Ambulance Response Time and Health Outcomes

Ambulance response time to emergency calls is a key indicator of a health system's efficiency although its impact on health is not precisely known. This causal relation is identified by exploiting rainfall at the time of the ambulance run as a shock to responsiveness. The elasticity of the likelihood of a severe cardiovascular condition with respect to response time is 0.9 and that of the likelihood of death before reaching the hospital is 5. Finally, the economic value of time is quantified, and it is shown that improving the ambulance's ability to locate the scene would substantially increase efficiency.