Updated Estimates of Potential Traffic Fatality Reductions With Automatic Collision Notification

摘要

This paper updates the earlier work done by Wu, Craig, et al. (2013) that explored the effects of earlier emergency medical services (EMS) through Automatic Collision Notification (ACN) on passenger/driver survivability using Fatality Analysis Reporting System (FARS) 2005-09. In this continuing study the earlier results are updated using recent FARS 2009-2012 data, while additional factors together with ACN are also considered: such as EMS arrival, time to hospital, urban/rural location comparison, occupant age and correlation between EMS factors. Kaplan-Meier estimator is applied to compare the survival rates between two conditions (e.g., earlier versus late EMS notification); Proportional hazard model explores simultaneously multiple risk factors related to traffic mortality. Correlations between notification and EMS arrival are explored and especially in rural area. Based on FARS data from 2009-2012, Kaplan-Meier life curves clearly show the benefits associated with earlier notifications within 1-2 minutes (approximately 1.5-2.0% fatality reduction within a timeframe of 6 hours after crash) and earlier arrivals. The relative hazard ratio associated with collision notification, location and age are obtained from a multiple regression model, and the relatively higher fatality hazard (up to 4% higher) is associated the later notification of more than 2 minutes. This paper obtains the driver/passenger survival probability differences over time under different conditions of collision notifications, EMS arrivals, time to reach a hospital, and crash locations, furthermore, this analysis provides the estimations of lives that could potentially be saved (177 to 244 per year approximately) due to earlier crash notification, or Automatic Collision Notification (ACN).