Countdown traffic lights a danger, study shows

Findings indicate a 26% rise in pedestrians being hit

The use of countdown timers at road crossings in Toronto is connected with a major increase in serious collisions involving pedestrians hit by cars, according to a new study published in the journal Injury Prevention.

The study, which looks at data collected from 2000 to 2009, says the number of pedestrians struck by cars at crossings increased by 26 per cent after the countdown timers were introduced. It also shows a 51 per cent increase in serious injuries and fatalities.

Dr. Andrew Howard, a pediatric orthopedic surgeon at Sick Kids hospital and one of the researchers, said he was “surprised” by the results.

He was part of an earlier study that looked at the same set of data but found different results. Released in 2011, the previous study found that the countdown timers had no effect, positive or negative, on safety.

“What this study does is . . . a better job of modelling the available data and separating out the effect of the signal from the other things that are going on, like the difference between summer and winter and the effect of time passing,” said Howard.

The report looked at data from 1,965 intersections between January 2000 and December 2009 and included 9,262 cases where pedestrians were hit by cars.

The results contradict an earlier study by a University of Toronto team that found the timed crossings actually made things safer for pedestrians (resulting in about five fewer pedestrians being hit than before), but more dangerous for cars (about 22 more vehicle-on-vehicle collisions on average). The two studies used different methodologies, sets of data and date ranges.

“I would presume that (with) multiple studies of this tool in different settings you’ll get multiple results,” said Howard. “It’s by putting them all together that you’re going to be able to find out how to deploy this technology to get safety benefits.”

Howard stressed that his results don’t mean that timed intersections should be abandoned.

Rather, he said, they highlight an opportunity to improve safety by altering variables such as the delay between the countdown finishing and lights changing.

Howard suggested that rushing the light, by both drivers and pedestrians, could be a factor contributing to the increase in accidents.

“If you run the mental script and watch what you really do, a lot of the time what you really do is try and get across the street because you think you’ve got the time to do so,” he said.