Hospital inpatient costs resulting from road crashes in Western Australia.

The purpose of this study was to estimate the inpatient costs of road crashes in Western Australia, and to investigate factors relating to casualties and their injuries that affect the hospital costs resulting from road crashes. All road crash casualties who were injured severely enough to be hospitalised in Western Australia in 1988 were included. A casemix classification system was used to classify patients into diagnostic related groups. Hospital costs were assigned to individual patients on the basis of their diagnostic related group and length of hospital stay. The annual cost of hospital treatment for road crash casualties was estimated as $13.9 million, and 33 per cent of this was incurred by those with lower extremity injuries and 27 per cent by those with head injuries. Hospital costs per casualty ranged from an average of $1388 for those sustaining minor (Abbreviated Injury Scale severity score of 1 or 2) spinal injuries to $16,580 and $33,424, respectively, for those sustaining severe (Abbreviated Injury Scale severity score of 4 or 5) head and spinal injuries. A multivariate analysis of variance revealed the following factors as having a significant independent effect on the hospital inpatient costs of road crash casualties: type of hospital (teaching or nonteaching), body region of injury, injury severity level and road user group. There were also significant interaction effects between different factors. Since hospital inpatient costs vary considerably across factors, using average cost data in the specific economic evaluation of road safety interventions for groups of road users is inappropriate.