Fatality and Injury Severity of Older Adult Motor Vehicle Collisions in Orange County, California, 1998–2007

Introduction: Injuries and fatalities in adult drivers 18–65 years of age have decreased in recent years due to safer vehicles, enhanced medical policies, and implementation of injury prevention policies. However, adult drivers over 65 years of age are continuing to suffer from motor vehicle collision-related injuries and fatalities at a more constant rate. A number of physiological factors contribute to the deterioration in visual acuity, slower reaction speeds, and decreased awareness in older drivers. The objective of this study was to examine injury severity and fatality rates in older drivers compared to their younger counterparts in Orange County, California. Methods: This study used the Statewide Integrated Traffic Record System data for Orange County for the years 1998–2007. Drivers were categorized into 4 age groups: 25–64, 65–74, 75–84, and older than 85 years of age. Injury severity was assessed by the investigating officer. Results: Of the 197,814 drivers involved in motor vehicle collisions, 178,481 (90.2%) were in the 25–64 age group; 11,397 (5.8%) were 65–74; 6,592 (3.3%) were 75–84; and 1,344 drivers (0.7%) were over 85. Those aged 25–64 had the lowest fatality rate per 100,000 people, 2.5, whereas those 75–84 had the highest fatality rate, 4.9. The percent of crashes involving a left turn increased with age, and the percent that were stopped in the road decreases with age. Change in injury collision involvement ratio in the 3 younger age groups decreased by 26% to 32%, but decreased by 18% among drivers aged 85 years and older. Conclusion: The decrease in collision fatalities was greater in the 25–64-year-old group compared to the older adult population. This disparity highlights the need for further injury prevention efforts for older drivers.