PMCs--an alternative to DRGs for trauma care reimbursement

Payments made for inpatient trauma care were compared using two different patient classification systems--Patient Management Categories (PMCs) and Diagnosis Related Groups (DRGs). Two databases were used in this study: 1) estimated costs for all inpatient claims from one large payor for adult injured patients (n = 5,256) treated at 79 acute care facilities (trauma centers and non-trauma centers) in one geographic region; and 2) hospital charges from statewide, all-payor Maryland data, including 25,987 adult injured patients. The accuracy of PMCs and DRGs in predicting actual costs was examined by level of injury severity and by types of hospital, trauma center vs. non-trauma center. Level of injury (minor, single significant, multiple significant, and major) were defined and operationalized using PMCs. Overall, both DRG and PMC payment systems were nearly equal to the actual costs associated with all injured patients. This relationship can be designed into the weighting scale used for payment. The distribution of DRG payments by injury severity level, however, is not reflective of the differential resources required to manage each patient type. In particular, multiple injuries and major injuries that require the specialized services of a trauma center were inaccurately categorized by DRGs and systematically underpaid by 21.0% to 39.0% by DRG payment. By contrast, the Patient Management Category System classifies patients into more clinically specific and accurate categories and offers a more equitable method of distributing payments by injury severity. These same relationships were also found at the hospital level, demonstrating the potential for use of PMCs as an equitable and viable alternative.