While it may be open to debate whether men or women are generally safer drivers, men over age 45 are much more likely to crash their vehicles on icy and snowy roads, according to a new study.
Those risks, notable as winter approaches, are even greater if the older men are driving four-wheel-drive pickup trucks, Purdue University researcher Fred Mannering found.
"There may be a sense of invulnerability with four-wheel drive trucks leading the drivers to not slow down as much as they should," Mannering said in an interview. "The reality is that four-wheel drive gets you up to speed faster in snow and ice, but it doesn't help you stop any quicker."
In addition, men under age 45 are more likely to get into serious accidents on dry roads, perhaps because of overconfidence, the study of single-vehicle accidents involving Indiana drivers indicates.
Female drivers of all ages, meanwhile, lose control and crash on rain-slicked roads most often because of their failure to sense reduced friction on wet pavement, Mannering's analysis of more than 23,000 police accident reports determined. But the crash rates involving women decline on snow and ice, Mannering said.
"I was somewhat surprised by the findings," said Mannering, who is associate director for research at Purdue's Center for Road Safety. He was assisted in the study by Abigail Morgan, a doctoral student at the university.
"My theory is that women tend to drive at the same speed regardless whether the road is wet or dry, failing to compensate for the reduced friction. But interestingly, women's crash rates do go down on snow and ice," he said.
The finding that not all groups of Indiana drivers underestimate the dangers equally as pavement becomes slicker is probably representative of drivers nationwide, he said.
"I expected the serious accident rate for men younger than 45 to be higher across the board in all road conditions," said Mannering, a civil engineering professor who studies the cause and effect of traffic accidents.
The new study data showed that younger men have a 21 percent higher likelihood of suffering severe injury while driving on dry roads than on wet roads, and a 72 percent higher likelihood on a dry road than on snowy and icy roads.
"The results of this study suggest the need to look more carefully at the process by which drivers assess and react to weather-induced road surface changes," the study concludes.