Natalie Shefsky coaxed the car keys from her aging mother when she felt the older woman no longer could safely drive. Now 67, Shefsky is on the lookout for changes in her own driving. Although she's still confident behind the wheel, some of her friends are less so, and she knows making quick judgments can get tougher with age.
"As I get older and my needs and my abilities change, I hope I retain my smartness to know [when] I can't do it," says the retiree from Northern Virginia.
Indeed, older drivers often do perceive changes in their abilities and voluntarily limit their driving in response. In a new study, Institute researchers found that the more memory and physical mobility problems people develop over time, the more limits they place on their driving.
Researchers surveyed the same group of drivers ages 65 and older every year for 4 years from 2006-08 to 2009-11 to find out how their driving habits were changing. They found that people who feel their memory or mobility is declining respond by avoiding certain situations such as driving on busy roads, at rush hour, or in the rain.
Older drivers tend to crash more often than middle-age drivers. However, crash rates, which have been declining overall, have dropped off more among older drivers than they have among younger adults (see "Older drivers' crash rates decline unexpectedly," June 19, 2010). The reasons aren't completely clear, but the tendency of older people to restrict their own driving is thought to play a significant role.
To better understand how drivers self-regulate, Institute researchers asked the study participants each year about any medical conditions and memory, vision, and mobility-related impairments and about their driving habits. By following drivers over several years, researchers were able to see how people's impairment levels changed over time and how they altered their driving habits in response.
Participants were recruited in Kentucky, Connecticut, and Rhode Island as they renewed their licenses. In the initial interview, most drivers reported at least some impairment, and the percentage of drivers who said they limit their driving increased with each added impairment (see "Older drivers' fatal crashes trend down," Dec. 27, 2008).
As memory problems or physical mobility impairments, such as difficulty turning one's head, increased, the number of driving situations people avoided also went up slightly. With each additional memory problem, for example, drivers reported an average increase of 0.18 in the number of driving situations avoided. Researchers also asked about vision impairments but found no relationship with the number of driving situations avoided.
Overall, the average number of driving situations people avoided increased from 2.5 the first year to 2.9 the fourth year. This increase might have been more pronounced if all the people who participated in the initial survey had remained in, but some dropped out.
Few drivers in the survey gave up driving, and, contrary to researchers' expectations, people didn't seem to cut back on driving in response to crashes. The biggest changes in the number of miles people drove were connected to life changes. Retirement, for instance, led people to drive 35 fewer miles per week on average, while losing a spouse led to an increase of 25 miles per week.
For her part, Shefsky says retirement hasn't reduced her driving, but it has allowed her to avoid heavy traffic. For a recent museum outing, for example, she and her friends left at 9 a.m. and came back at 3 p.m. "Why put ourselves through rush hour?" Shefsky says.
One reason Shefsky drives so much is that, while she hasn't felt the need to limit her driving, many of her friends have. For example, one doesn't like to drive in unfamiliar areas, and another isn't confident at night. As a result, when they go out together, they tend to take Shefsky's car.
"Seniors," Shefsky says, "are more aware of what they can do and what they can't."