Abstract
The Federal Highway Administration proposed guidelines for highway design to increase the safe-driving ability of older drivers; however, little empirical evidence exists to support these guidelines. This study investigated the effects of improved versus unimproved intersections, using a high-fidelity driving simulator. Kinematics measures and behavioral evaluations were obtained to determine whether driving performance during negotiation of improved intersections was safer for older (65-85 years) and younger (25-45) drivers. Five pairs of intersections were compared. Three of the 5 comparisons indicated significantly greater lateral control stability (as measured by maximum yaw rate) during turns at the improved intersections. This preliminary report is based on data from 19 subjects (5 young and 14 older adults). Despite the small sample size, the findings of this study suggest that some of the Federal Highway Administration guidelines for implementing safe road conditions are helpful in defining intersection characteristics that could lead to safer driving by both older and younger adults. These results may yield critical information for engineers, planners, policymakers, and others involved in the design of roadway systems to enhance safe driving.