Advanced Automatic Collision Notification Research Report
The National Highway Traffic Safety Administration (NHTSA) analyzed the safety potential and technical considerations of post-crash advanced driver assistance systems, namely automatic collision notification (ACN) and advanced automatic collision notification (AACN). ACN and AACN provide automatic post-crash information to first responders during an emergency when a crash reaches a minimum severity indicator threshold, such as an air bag deployment. Crash information is then transmitted to first responders via cellular signal including current vehicle location and vehicle identification information. These systems enable earlier crash notification, allowing quicker response. AACN also provides information on the probability of severe injury, which can lead to improved dispatch and transport decisions.
This study conducted a benefit-cost analysis by implementing injury prediction algorithms used by AACN systems. The injury prediction algorithm predicts the probability of severe injury for the vehicle occupant. Data from the Fatality Analysis Reporting System (FARS) and National Automotive Sampling System – Crashworthiness Data System (NASS-CDS) were used in the analysis. The average motor vehicle occupant fatalities were 21,934 fatalities for a seven-year period, 2009-2015. The data included whether a fatal crash victim was admitted to a local community hospital or a trauma center. The fatality data were evaluated on whether they would benefit from the AACN system. The benefit of preventing a fatality was calculated as $6,714,814 per fatality. The cost was estimated by the number of occupants with minor injuries unnecessarily treated at a trauma center multiplied by the cost treatment at a trauma center ($7,500).The benefit of the AACN system was estimated using mathematical models to estimate survival probability over time.
- The survival method showed that patients who received treatment quicker had higher chances of survival. When comparing 3, 6, and 12 hours of time between the crash occurrence and medical treatment, the survival rate ratio increased by 1.6 percent (from 6 to 3 hours) and 1.3 percent (from 12 to 6 hours).
- When combining the benefits of trauma center care for severely injured patients and the benefits of faster crash notification, an estimated reduction of fatalities of approximately 1.6 to 3.3 percent per year could be realized with implementation of AACN, and more than double the potential lives saved by earlier notification alone.
- At the CDC recommended injury risk threshold of 20 percent, benefits of AACN exceed costs by about $2.18 billion.