Driving behavior in a stratified sample of persons aged 65 years and older: Associations with geographic location, gender, age, and functional status

The growing number of older drivers has made safe personal mobility of the older population a topic of concern for policy makers, particularly since driving is the only means of transportation readily available in many geographic locations. Age is accompanied, to varying degrees and at varying rates, by cognitive and physical changes that adversely affect the ability to interact with the traffic environment. It has been proposed that older drivers reduce their traffic risk by adapting their driving behavior to “compensate” for declining abilities. However, relatively little research has been done on the driving activity of older drivers, and differences related to the geographic setting have been largely overlooked. This study sought to obtain specific information, by means of semi-structured, in-person interviews, on the driving activity of a random sample of drivers age 65+ living independently in different geographic settings within King County, Washington, in order to examine how geographic location, gender, age, functional status and activities were associated with driving activity. The sample was stratified to equalize the distribution across geographic (urban, suburban, and rural), gender, and age groups.; The study found that location, gender, age, functional status and activities each had statistically significant associations with one or more measures of driving exposure. Urban residents made frequent trips, but drove relatively few miles, and drove less on freeways. Rural residents drove relatively infrequently, but had high mileage. Suburban residents made frequent trips and also had relatively high mileage. The relatively younger drivers drove more at night and in snow and drove more miles than older drivers. Males drove more miles and more frequently than females. The more fit group drove more frequently and more miles, more at night and during rush hour than did the relatively more impaired group. The study did not find that the participants consciously restricted their driving activity in order to compensate for impairment. Nonetheless, there was evidence of lower exposure to the traffic environment among the relatively more impaired group.