Impact of Left-Turn Phasing on Older and Younger Drivers at High-Speed Signalized Intersections

Abstract

The study reports on research that evaluated the impact of different types of left-turn phasing on older and younger drivers at high-speed signalized intersections. Using Poisson regression, the likelihood that a driver in a particular age group would be responsible for a left-turn crash under different types of phasing was evaluated. The induced exposure method was used to estimate exposure by age group. The variable of interest was left-turn crash rate for left-turning drivers who were responsible for circumstances contributing to the crash. Older drivers had higher crash rates than younger or middle-aged drivers for all types of phasing. Younger drivers had higher crash rates than middle-aged drivers for all types of phasing. All three age groups had the highest crash rate under protected/permitted and then permitted phasing within their respective age group.