Gender differences in road traffic injury rate using time travelled as a measure of exposure

There is no consensus on whether the risk of road traffic injury is higher among men or among women. Comparison between studies is difficult mainly due to the different exposure measures used to estimate the risk. The measures of exposure to the risk of road traffic injury should be people's mobility measures, but frequently authors use other measures such population or vehicles mobility. We compare road traffic injury risk in men and women, by age, mode of transport and severity, using the time people spend travelling as the exposure measure, in Catalonia for the period 2004-2008. This is a cross-sectional study including all residents aged over 3 years. The road traffic injury rate was calculated using the number of people injured, from the Register of Accidents and Victims of the National Traffic Authority as numerator, and the person-hours travelled, from the 2006 Daily Mobility Survey carried out by the Catalan regional government, as denominator. Sex and age specific rates by mode of transport and severity were calculated, and Poisson regression models were fitted. Among child pedestrians and young drivers, males present higher risk of slight and severe injury, and in the oldest groups women present higher risk. The death rate is always higher in men. There exists interaction between sex and age in road traffic injury risk. Therefore, injury risk is higher among men in some age groups, and among women in other groups, but these age groups vary depending on mode of transport and severity.