Many older baby boomers will turn 65 this year - the largest generation of senior citizens ever to own driver's licenses.

The influx of senior drivers may make it the right time to start implementing physician-mandated screenings to check whether some are medically fit to take the wheel, say some physicians.

"The restriction of licenses throughout Canada generally occurs only after accumulation of moving violations," Dr. Donald Redelmeier, a professor of medicine at the University of Toronto, wrote in an editorial published today in the Canadian Medical Association Journal.

"This approach is often too late to prevent injuries," Redelmeier wrote.

Sixty-nine percent of Americans ages 55 and older use more than one medication that can affect their driving, according to a 2009 study by the AAA Foundation.

Graduated licensing programs that have restricted night and highway driving for young adults seem to have reduced the accident rate in both Canada and the U.S.  Redelmeier proposed similar programs for the elderly.

"The principle is to prevent trauma rather than to await a series of incidents before taking any action," Redelmeier wrote.

But some researchers say physicians are overestimating how dangerous elderly drivers really are.

While it's true that the older you get, the more likely you are to get in a crash, current data shows teenage drivers are far more likely to get into a crash than the elderly, according to Ezra Hauer, a professor in the department of civil engineering at the University of Toronto.

"In spite of what data show consistently, almost one-third of Canadians believe that elderly drivers are a 'very or extremely serious traffic safety problem,'" Hauer wrote in a commentary published in the Canadian Medical Association Journal.

That perception may also apply to physicians who could be tasked to screen the elderly, he said.