Longitudinal Analysis of Fatal Run-Off-Road Crashes, 1975 to 1997

Abstract

Data from the Fatality Analysis Reporting System and the National Personal Transportation Studies were used to study run-off-road (ROR) fatal crashes over the period 1975–1997. Longitudinal trends in roadside crashes were analyzed to see how driver characteristics such as gender, age, and alcohol usage relate to ROR crashes. ROR crash rates, adjusted for driving exposure, have decreased 40 percent for male and female drivers since peaking in 1980. The greatest improvement has occurred at night on rural and urban non-Interstate highways. Young drivers, male drivers, drivers over 70 years of age, utility vehicles, rollovers, and alcohol pose special challenges for roadside safety improvements efforts. Male drivers have higher ROR crash rates than females, even after adjusting for driving exposure. Males aged 20 to 24 have ROR crash rates 3.3 times those of females of the same age. Using ROR crash rates for female drivers aged 40 to 49 as a base, ROR rates for teenage males are 20 times as high and for teenage females 9 times as high. For drivers aged 70 and older, these ratios are 4.5 for males and 4.0 for females. Alcohol involvement in ROR crashes is nearly 50 percent for male drivers aged 20 to 39 and is more than 50 percent for all drivers during dark conditions. From 1975 to 1997 the number of utility vehicles involved in ROR crashes increased nearly 600 percent. Seventy percent of fatal ROR crashes with utility vehicles involve a rollover. Rollovers rates for vans and pickups involved in fatal ROR crashes are nearly five times those for non-ROR crashes.