Car safety and social differences in traffic injuries among young adult drivers: a study of two-car injury-generating crashes in Sweden

Objective—The study examines whether socioeconomic and sex differences in road-traffic crashes leading to injury vary according to car-safety level.Method—Individuals records of subjects born 1970–1972 registered in the Swedish Census of 1985 (n = 334,070) are linked to road-traffic-crash data for the period 1988–2000 for first police-registered two-car crashes leading to severe or fatal injury (n = 4875). Injuries are split into categories according to level of car safety on a five-point scale, based on criteria related to crash safety. Account is taken of both how the car is constructed and the effectiveness of its safety equipment (such as airbags and seat belts). For each car-safety level, relative risks are computed considering socioeconomic groups of origin, educational level, and sex.Results—No substantial differences between drivers in different socioeconomic positions of origin is observed except for crashes involving cars 30% better than average with regard to safety. There are consistent risk differences across all car-safety categories according to educational level. Male drivers show an elevated risk of injury in all car categories, except for cars with the poorest safety where they are at significant under-risk.Conclusions—Car-safety level impacts on social differences in road-traffic injury risks in specific and restricted manners. Car-safety development is an important factor in improved road safety, but it may not benefit all to the same extent.