Did doctor warnings reduce car crashes?

By Julia Belluz - Wednesday, September 26, 2012 at 5:54 PM - 0 Comments

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To this day, Dr. John Crosby, a family physician in Cambridge, Ont., remembers the scene perfectly: “She chased me around my waiting room with a walker, screaming and yelling.” The doctor dodged in and out of chairs to avoid getting beaten. “She” was one of his patients. Months later, when she was admitted to hospital and Dr. Crosby went to visit her, she greeted him with: “Oh! If it isn’t Big John Crosby.” She’d never forgive him, she said, not even on her deathbed.

The offense? Dr. Crosby had reported her to the Registrar of Motor Vehicles because she had dementia, and by his calculation, was a potential hazard behind the wheel. In Ontario, according to the Highway Traffic Act, physicians are legally required to report patients who are suffering from a condition that may impair their ability to drive. This is part of their role as guardians in our society, alongside other unpleasant duties like filing reports about gunshot wounds or suspected child abuse. But just because it’s a legal and professional obligation doesn’t make the task any less painful. “It’s one of the hardest things,” said Dr. Crosby. “Patients are always furious with you, no matter what.”

This is why doctors dread telling patients they may be unfit to drive, and it’s why, in 2006, Ontario introduced a financial incentive—$36.25 that doctors could bill the province—for each time they tell on a patient.

Six years later, a New England Journal of Medicine study released today, finds that the rate of reporting by doctors has increased since 2006 and patients who’d received a formal RMV warning were 40 to 45 per cent less likely to be involved in a serious car crash. “In our study, the baseline risk in this cohort of patients was 4.7 serious crashes per 1,000 drivers per year,” said Dr. Donald Redelmeier, a senior scientist at the Institute for Clinical Evaluative Sciences (ICES) and lead author of the report. After the warning, the risk came down to 2.7 serious crashes per 1,000 drivers per year.

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Accident prone? Here's why

By Kate Lunau - Tuesday, July 8, 2008 at 2:08 PM - 0 Comments

Bad drivers take note: researchers from Toronto’s York University say they’ve pinpointed part of the brain that could be to blame.

People can generally keep track of three or four different things—whether it’s another moving car, a traffic light or pedestrian—without keeping their eyes glued on them. “You don’t remember all the details, but you’ve got this general sketch,” says Dr. Doug Crawford, Canada Research Chair in Visual-Motor Neuroscience and lead author of the study. Called the “visual map,” this helps us navigate our environment and keep track of our surroundings. But these landmarks can easily be disrupted, new research shows.

In the study, to be published this month in The Journal of Neuroscience, the team of researchers temporarily interfered with subjects’ visual maps by using a magnetic pulse on the brain’s parietal cortex (while the pulse has no longterm effects, it “scrambles things up a bit,” Crawford says). After introducing the pulse, “It’s as if we took away the memory of where those things were,” he explains. When this brain function is reduced, people might think they’re observing a complete scene—when in fact they’re missing some vital pieces of information. Continue…