The severity of road traffic crashes resulting in hospitalisation in New Zealand.

Road trauma is a major contributor to premature mortality and to morbidity in New Zealand. Existing published data on road crashes do not provide an adequate basis from which to develop prevention priorities because they are, in some cases, limited to certain classes of crashes with no adequate measures of anatomical severity, economic costs, and disablement. This paper describes road traffic crashes in terms of anatomical severity. Motor vehicle and nonvehicle crashes occurring on public roads were included. Using International Classification of Diseases E-codes, cases were selected from a file that contains information on all dead and live discharges from all public hospitals in New Zealand. Abbreviated Injury Scale scores were estimated from injury diagnoses using a computer programme specifically written for that purpose. A total of 9201 cases were identified. There were significant differences in the distribution of injury sites by class of road user. The majority (59%) of injuries were of moderate severity. Pedestrians sustained a disproportionate number of the severe/critical injuries. Compared to other causes of injury, road traffic crashes had a higher proportion of the severe/critical cases (5% versus 1%). Using motor vehicle occupants as the baseline category, the relative risk per kilometre travelled for sustaining a hospitalised injury was 55.6 for motorcyclists and 25.8 for bicyclists.