Crashes per capita are lower among older drivers than people in any other age group, mostly because fewer older people have licenses and those who do drive fewer miles. But when older people get behind the wheel, their risk of crashing and dying is high.
A challenge is to identify problem drivers before they crash — and even if the hazardous ones can be identified, then what? Rely on education to reduce the risk or resort to stronger measures such as imposing license restrictions?
A number of approaches are being tried. For example, provisions in some states require people older than specified ages to renew their licenses more often, thus creating more frequent screening opportunities. Such provisions apply in addition to the usual ones designed to identify drivers of all ages who no longer meet licensing standards because of physical or mental infirmities.
Officials in a few states are trying vision tests or road tests. Where these approaches have been evaluated, results are mixed.
Vision screening in Florida
Since 2004 people 80 and older applying to renew their licenses have had to pass a vision test. Rates of renewal remain high among the older people. Eighty percent of those eligible to renew in 2004 and the first half of 2005 applied, and 93 percent of them passed the vision test on the first or a subsequent try. These findings are from an Institute study conducted with University of Alabama researchers.
Florida's older drivers with poor vision may be responding to the new requirements by taking themselves off the road. About half of the drivers who chose not to renew their licenses said it was because they thought they'd fail the vision test. Those who chose not to renew were older and in poorer health. They also were more likely to be women and single rather than married.
Tiered licensing in California
Officials are testing three-tier license renewal for all drivers, not just older people. The first two tiers involve driving knowledge and physical screening (vision, physical limitations, etc.). Results of these tiers determine whether the third tier, a road test, is warranted.
Evaluation of 152 older drivers seeking renewal found that lower assessment scores in the first tiers predicted worse performance in the road test. But the scores didn't do a good job of predicting who had crashed at least once in the previous 3 years, and it's questionable whether they'd be any better predictors of what licensing officials really need to know, which is future crash likelihood.
A study in Maryland found that drivers 55 and older who had poor scores on selected cognitive evaluations were about 25 percent more likely than drivers with better scores to be at fault in crashes during the next 5 years. The strongest predictors of crash risk were tests of divided attention and visual perception. This points to a general relationship between measures of cognitive ability and crash risk. However, test accuracy isn't good enough to base licensing policies on the results.
A potential way to reduce the risk for older drivers is to educate them or, more likely, re-educate them after years on the road. A number of organizations offer this. For example, a 6.5-hour classroom course in California succeeded in reducing the participants' subsequent traffic violations but not their future crash rates. This finding is in line with a wealth of previous research (see Status Report special issue: Highway safety gets short shrift, Dec. 7, 2002) indicating that education alone doesn't produce safer drivers.
Nor was any benefit found from mailers to 40,000 California drivers 70 and older who had been in crashes or cited for violations. These drivers received various materials, none of which produced subsequent differences in driving records versus people with crashes or citations who weren't contacted.