Translating road safety into health outcomes using a quantitative impact assessment model

Introduction: The majority of traffic safety policies are limited to preventing mortality. However, nonfatal injuries also impose a significant risk of adverse health. Therefore both mortality and morbidity outcomes should be included in the evaluation of traffic safety policies. We propose a method to evaluate different policy options, taking into account both fatalities and serious injuries.
Methods: A health impact model was developed and aligned with a transport and road safety model, calculating the health impact of fatalities and seriously injured traffic victims for 2 transport scenarios in Flanders and Brussels (Belgium): a base scenario and a fuel price increase of 20% as an alternative. Victim counts were expressed as Disability Adjusted Life Years (DALY), using a combination of police and medical data. Seriously injured victims were assigned an injury, using injury distributions derived from hospital data, to estimate the resulting health impact from each crash. Health impact of fatalities was taken as the remaining life expectancy at the moment of the fatal crash.
Results: The fuel price scenario resulted in a decrease of health impact due to fatalities of 5.53 - 5.85% and 3.37 - 3.88% for severe injuries. This decrease was however not equal among all road users.
Conclusion: With this method the impact of traffic polices can be evaluated on both mortality and morbidity, while taking into account the variability of different injuries following a road crash. This model however still underestimates the impact due to nonfatal injuries.