Fatal Crashes among Older Drivers: Decomposition of Rates into Contributing Factors

This study selected US drivers aged 55 years or older who were involved in fatal crashes in 1990 and 1995 and explored factors that influenced their fatal crash involvement rate. The fatal crash involvement rate (risk of being involved in a fatal crash) can be thought of as the product of the crash fatality rate (risk of dying given a crash), the crash incidence density (risk of crash), and the exposure prevalence (amount of driving). Fatal crash involvement rates increased with age. The relative contributions of the crash incidence densities and exposure prevalences were greater than that of the crash fatality rates. The decomposition methodology was shown to be a useful method for investigating the potential benefit of crash prevention interventions aimed at different components of the fatal crash involvement rate.