Elderly Drivers Fail a Test

True or false? Most older drivers drive as safely as anyone else. It’s just that a few bad apples, particularly those behind the wheel despite poor vision or dementia, make mistakes and produce the statistics showing that per mile driven, drivers over age 75 are almost as dangerous as teenagers.

I want this to be true, given how dependent Americans of all ages are on automobiles. In many parts of the country, a senior who gives up the keys is doomed to relying on friends and family, or on senior transit systems of varying usefulness. When recalcitrant older drivers and agonized adult children — like Irene Wielawski, who wrote here about disabling her mother’s car to keep her off the road — fear that relinquishing the car means giving up independence, they aren’t wrong.

But researchers in Australia, using a novel method to gauge how well people drive, have concluded that serious errors are alarmingly commonplace. “We are seeing a ubiquitous increase in driver errors with age,” said Kaarin Anstey, a psychologist at Australian National University and lead author of the report, just published in the journal Neuropsychology.

Dr. Anstey and her co-author, Joanne Wood, administered a battery of cognitive tests to 266 adults ages 70 to 88 and asked them about their driving history — standard stuff. But then the researchers took their subjects out on the road for a 12-mile swing through urban and suburban Brisbane in a dual-brake car. A professional driving instructor in the passenger seat directed the driver for part of the route, but for about a quarter of the course, the driver had to follow signs and find his or her own way to an unfamiliar destination. In the back seat, a trained occupational therapist observed and recorded everything from unsignaled lane changes to speeding to abrupt stops.

“It’s not just looking at crash records,” Dr. Anstey explained in an interview. “This is a look at live driving performance. The on-road data gives us much more information.”

That information is sobering. “You will always have people in their 90s who are excellent drivers,” Dr. Anstey acknowledged. But among these older adults, all of whom drove at least once a week, the rate of all kinds of on-the-road errors rose significantly with age.

And the so-called critical errors — in which the instructor in the front seat either had to grab the wheel or hit the auxiliary brake to avert a crash — quadrupled among the eldest drivers, compared with the youngest. Those ages 70 to 74 averaged less than one critical error during the nearly hourlong excursion; those older than 85 averaged almost four.

And these were independent seniors who, tests showed, didn’t have dementia or impaired vision. “They’re probably slightly healthier and higher-functioning than the general older population,” Dr. Anstey said. Yet to the researchers’ surprise, 17 percent of the older drivers made critical errors.

Their most common mistake, by far, was not checking the car’s blind spots. That was followed by problems with lane positions — veering left or right, or choosing the wrong lane for a turn — and a failure to use directional signals. Men and women performed equally well, or equally badly.

Declines in brain function, not merely slower reaction times, caused these blunders, the researchers’ cognitive tests suggested. As we age, “the ability to switch between tasks and keep track of what you’re doing worsens — looking around, taking in complex information within a limited time frame,” Dr. Anstey said. We also lose some ability to distinguish between what we need to pay attention to and what we don’t.

Dr. Anstey doesn’t endorse restricted driving privileges based on age. “We believe driving should be based on actual functional capacity,” she said. In fact, she thinks her findings could be used to develop programs that would retrain seniors to drive. “I don’t see why we couldn’t train people to check the blind spots,” she said. “We can also put in extra blind-spot mirrors to improve visibility.”

And as we’ve reported here, various initiatives are under way to keep unsafe older drivers off the highways while allowing safe ones to maintain their mobility. Iowa’s experiment, which we’ve discussed, looks promising. So do alternatives like the Independent Transportation Network.

We’re going to need such options. If we’re like elderly Australians (and the researchers could see no reason their findings wouldn’t apply equally to elderly Americans), most of us are increasingly apt to become unsafe drivers as the years pass. Not a happy situation.