Surgical case costing: trauma is underfunded according to resource intensity weights.

ObjectiveTo determine whether rate-based funding using resource intensity weights (RIWs) adequately represents trauma case costs.DesignA prospective time-in-motion resource utilization pilot study to assure the effectiveness of the computerized hospital Transition-One data acquisition system, followed by a retrospective observational case costing study. Patient costs with no identifing data were used, and all costs were tabulated as mean cost per group.SettingLondon Health Sciences Centre, London, Ont., a tertiary care "lead" trauma hospital.PatientsA modified random selection of 4 control case mix groups (CMGs) of surgical patients for the fiscal year 1996-97. The trauma group was selected as a representative resource-intensive CMG. Each patient was assigned to a CMG by Health Records according to the most responsible diagnosis.Outcomes measuresTotal case costs were tabulated for each patient then combined for a mean case cost per CMG. The RIW assignments for each patient were combined to create a mean RIW per CMG and mean length of stay per CMG.ResultsThere was no statistically significant difference between the control surgical CMGs and the trauma CMG for mean RIW-adjusted length of stay per CMG, but there was a significant difference (p < 0.0001) between the control CMGs and the trauma CMG for RIW-adjusted mean case cost per CMG.ConclusionsRIWs underrepresent trauma case costs by a factor of 3.5, which could result in underfinding and potential fiscal difficulties for leading trauma hospitals as has occurred in the United States.