The independent contribution of driver, crash, and vehicle characteristics to driver fatalities

Abstract

Several driver, crash, and vehicle characteristics may affect the fatality risk of drivers involved in crashes. To determine the independent contribution of these variables to drivers' fatality risk, we used data from single-vehicle crashes with fixed objects contained in the US Fatal Accident Reporting System. A multivariate logistic regression revealed that the odds ratio (OR) of a fatal injury increased with age, reaching 4.98 (99% confidence interval (CI) = 2.01-12.37) for drivers aged 80 + compared with drivers aged 40-49 years. Female gender (OR = 1.54, 99% CI = 1.35-1.76) and blood alcohol concentration greater than 0.30 (OR = 3.16. 99% CI = 1.96-5.09) were also associated with higher fatality odds. In comparison with front impacts, driver-side impacts doubled the odds of a fatality (OR = 2.26, 99% CI = 1.92-2.65), and speeds in excess of 111 kilometers per hour (kph: 69 mph) prior to or at impact were related to higher fatality odds (OR = 2.64, 99% CI = 1.82-3.83) compared with speeds of less than 56 kph (35 mph). Three-point seatbelts were protective against fatal injuries (OR = 0.46, 99% CI = 0.39-0.53 compared with no belt). These data suggest that increasing seatbelt use, reducing speed, and reducing the number and severity of driver-side impacts may prevent fatalities. The importance of age and gender suggests that the specific safety needs of older drivers and female drivers may need to be addressed separately from those of men and younger drivers.