Epidemiology of trauma: a population-based study of geographical risk factors for injury deaths in the working-age population of Norway.

INTRODUCTION: Trauma is a major global cause of morbidity and mortality. Population-based studies identifying high-risk populations and regions may facilitate primary prevention and the development of optimal trauma systems. This study describes the epidemiology of adult trauma deaths in Norway and identifies high-risk areas by assessing different geographical measures of rurality.
METHODS: All trauma-related deaths in Norway from 1998 to 2007 among individuals aged 16-66 years were identified by accessing national registries. Mortality data were analysed by linkage to population and geographical data at municipal, county and national levels. Three measures of rurality (centrality, population density and settlement density) were compared based on their association with trauma mortality rates.
RESULTS: The study included 8466 deaths, of which 78% were males. The national annual trauma mortality rate was 28.7 per 100,000. Population density was the best predictor of high-risk areas, and there was a consistent inverse relationship between mortality rates and population density. The most rural areas had 52% higher trauma mortality rates compared to the most urban areas. This difference was largely due to deaths following transport-related injury. Seventy-eight per cent of all deaths occurred in the prehospital phase. Rural areas and death following self-harm had higher proportion of prehospital deaths.
CONCLUSION: Rural areas, as defined by population density, are at a higher risk of deaths following traumatic injuries and have higher proportions of prehospital deaths and deaths following transport-related injuries. The heterogeneous characteristics of trauma populations with respect to geography and mode of injury should be recognised in the planning of preventive strategies and in the organisation of trauma care.