No driving for Miss Daisy

The rising use of computerized testing to determine whether people are medically fit to drive is causing a stir in the Canadian seniors community — and raising questions about the effectiveness of current methods of assessment.

Moreover, a popular mechanism for testing seniors, a computer program known as DriveABLE that is used in seven provinces and territories, is biased against seniors, says Carol Libman, advocacy consultant for the Canadian Association of Retired Persons (CARP).

Libman says the association has received numerous complaints from seniors frustrated with their experiences with DriveABLE, which is used in Ontario, Quebec, Nova Scotia, British Columbia, Manitoba, Alberta and the Yukon Territory (www.driveable.com/index.php/contact-diriveable/canadian-locations). “They find that this thing is really intimidating,” she says, “and not a fair test of cognitive ability, or driving ability.”

Although widely used, programs like DriveABLE should not be the sole determinant of a senior’s capacity to drive, says Dr. Malcolm Man-Son-Hing, a geriatrician at the Ottawa Hospital in Ontario. “It can give some indication,” he says. But “you can’t hang your hat on any single test out there.”

“It’s really a clinical judgment,” Hing adds. “Who else is in a better position to make that call than their physician?”

But DriveABLE developer Allen Dobbs rejects the notion that the program is biased against seniors. Dobbs says results from the computerized portion of the test reflect the individual’s level of cognitive ability, not their age.

“It’s not age. It really is [based on] the medical condition,” Dobbs says. “Granted, the older you get, the more likely you are to have one of those medical conditions, but it really is the condition.”

Libman, though, says many seniors complain they are disadvantaged because the “DriveABLE Cognitive Assessment Tool” test uses unfamiliar touch-screen technology. Put an eight-year-old in front of the computer and it’s possible they could pass the test. But that doesn’t mean the child is fit for the roads. “As far as we are concerned, it is being relied on too heavily as a test for safe driving,” Libman says, adding that everyone who takes the cognitive portion — pass or fail — should be allowed to take a road test.

Experts say there’s no scientific standard for determining whether a senior citizen can still drive safely, but medical red flags include moderate to severe dementia, drug use impairing cognitive and/or motor function, and multiple physical deficits that combine to reduce the patient’s driving ability.

Image courtesy of © 2011 Jupiterimages Corp.

DriveABLE is software that its marketers claim can judge, based on an in-office computer test and, if necessary, an on-road test, whether an individual is fit to drive (www.driveable.com/index.php/about-driveable). The test was developed over the course of eight years by Dobbs, then the director of the neurocognitive research unit within the Northern Alberta Regional Geriatric Program, and colleagues. Results form the basis of recommendations on whether to revoke a person’s licence. Doctors and, in some cases, licensing authorities, refer those they feel are at risk to a Drive-ABLE office for testing, says Dobbs.

“People who can no longer drive safely are sick,” says Dobbs. “Most often, they have some type of progressive illness, which means that not being able to drive is just one of the many losses the person is going to suffer.”

According to a demonstration video on the DriveABLE website (www.driveable.com/index.php/videos/63-videos/144-demo-video.html), an individual is asked to complete a series of tasks designed to test basic cognitive functions like motor speed and control, spatial judgment and decision making, as well as the speed of attention shifting.

The test scores are analyzed by the DriveABLE server, which issues a report outlining a person’s score and the probability that he would fail a road test. If a person falls below a certain line, he’s deemed unfit for the road. If he scores higher than a certain marker, he passes the cognitive portion. In both cases, a road test is deemed unnecessary.

But those whose scores fall between these two points are required to complete a driving test, administered by a DriveABLE instructor, Dobbs says.

How do these tests measure up against a traditional physician’s assessment?

Hing and a colleague, Dr. Shawn Marshall of the Ottawa Hospital Rehabilitation Centre, are conducting a five-year study of senior Canadian drivers (www.cihr-irsc.gc.ca/e/39178.html), in which they are taking 1000 subjects older than age 70 and annually evaluating their medical, psychological and functional health. Their vehicles are also outfitted with global positioning systems that will allow Hing and Marshall to analyze their driving habits.

“Some of them will crash in the next five years, and some of them won’t,” Hing says, adding that the goal is to create a standardized test that will take the guesswork out for doctors as to whether a patient is safe for the roads.

In 7 of 10 provinces, as well as all 3 territories, physicians are legally obligated to report patients they feel are medically unfit to drive to licensing authorities (www.cma.ca/multimedia/CMA/Content_Images/Inside_cma/WhatWePublish/Drivers_Guide/Section03_e.pdf). Failure to do so could subject the physician to liability if a patient is subsequently involved in an accident. In Nova Scotia, Quebec and Alberta, doctors are given discretion as to whether to report a patient’s fitness to drive.

In making a determination, Hing takes into account recent accidents, as well as direct information from a patient’s family, such as whether they would feel safe if their child was a passenger in a car driven by the patient.

Medical red flags include moderate to severe dementia, drug use and multiple physical deficits that combine to reduce the patient’s driving ability (www.cma.ca/multimedia/CMA/Content_Images/Inside_cma/WhatWePublish/Drivers_Guide/Section07_e.pdf).

The problem is that there’s no scientific standard for making the call, Hing says. Some doctors are too strict and others, too lenient. “That kind of variation in practice is rather unfair. … It puts a huge strain on the physician–patient relationship.”

Creating a scientifically sound and easy-to-use test will lessen physician reliance on factors like age in making that determination, Hing adds. “Age in itself is not a good criterion to determine whether older persons are fit to drive.”