Older men driving on snow and ice, women driving on rain-slick highways and younger men on dry roadways face more risk of serious injury, U.S. researchers say. The study of Indiana drivers was conducted by Purdue University and analyzed 2007-2008 police report crash data of 23,431 Indiana drivers, a university release said Monday. \"I would say Indiana is pretty representative of the nation as a whole because it is average in terms of climate and socio-demographics, so these findings might be similar nationwide,\" Fred Mannering, a professor of civil engineering, said. A surprise finding was that men younger than 45 showed a 21 percent higher likelihood of severe injury while driving on dry roads than on wet roads and a 72 percent higher likelihood of severe injury on a dry road than on snowy and icy roads, Mannering said. \"Younger men may be tempering some of their aggressive driving behavior to compensate for the compromised roadway surface under adverse weather conditions,\" Mannering said. \"But they seem to let such behavior loose on dry roads and may be underestimating the severe crash risk in good weather conditions.\" Men 45 and older are 5.5 times more likely to be severely injured or killed when driving on snowy and icy road surfaces when driving on wet surfaces, the study found. \"It\'s noteworthy that older men driving pickup trucks were 81 percent more likely to be injured on snow and icy surfaces than those older men driving other vehicle types,\" Mannering said. \"This could reflect overconfidence or a false sense of safety in such vehicles, which are generally larger.\"