The research reported investigated the utility of using computer-controlled video driving scenarios as measures for screening functional aspects of driving performance possibly affected by factors associated with aging. The goal of the research was to provide driving-performance-specific feedback to elderly drivers so that they might be better able to make informed decisions about whether, and under what circumstances, to continue driving. The assessment system utilizes ordinary personal desktop or laptop computers, and video scenarios placed on videodisc. Drivers view these driving scenarios on ordinary large-screen TV monitors, while they operate accelerator and brake pedals to drive at preferred speeds under various conditions, and to brake when appropriate events in the video scenarios occur. The computer interface was designed for simple, user-friendly manual operation of the video presentations, as well as for fully automatic presentations. The scenarios include Traffic Events in which drivers may respond to the onset of brake lights in lead cars or rapid closures of gaps between vehicles, intrusions of other vehicles and pedestrians, stop signs and traffic signals, and tennis balls or basketballs rolling into the road in suburban residential areas. These are produced in full illumination and in reduced illumination (dusk) variations. Scenarios in which drivers proceed at their own pace include highway driving in excellent road conditions and light traffic, wet snow-rain conditions, heavy rain, and night driving with oncoming headlight glare. The performances of 170 drivers 17-91 years of age, with 109 drivers being at least 55 years of age, were assessed. Results indicated that significant age group differences could be found on a number of the measures. Also, several measures were significantly related to accident risk. Driving speeds appeared related to actual driving habits, and older drivers drove slower than younger drivers, but primarily in poor visibility conditions, especially those involving oncoming headlight glare. The highest predictions were obtained by separating older and younger drivers into groups over and under 65 years of age, since responses to different driving scenarios were related to crashes in the different age groups. Many persons over 75 years old, and two individuals with cataract problems failed to see small objects portending a possible emergency event. Two persons in their 70s manifested "unintended acceleration" responses when sudden intrusions occurred in their driving routes. Two patterns of behaviour related to accident risk in older drivers were noted. One was a slowed decision phenomenon, in which drivers recognized their slowed decisions and behaviours, drove slowly in compensation, but still were prone to have accidents. The other was a "macho" pattern in which a few older drivers drove relatively fast, while manifesting some slowing of decision and response time. (A)
Samenvatting