Classifying patients with burns for hospital reimbursement: diagnosis-related groups and modifications for severity

This study was designed to evaluate the relative severity and resource consumption of hospitalized patients with burns in a national cross section of hospitals, both with and without burn centers. We investigated to determine whether clinical variables or severity of illness measures not recorded in the Uniform Hospital Discharge Data Set are significant in explaining variation in length of stay, total cost, and mortality for patients with burns. The ability of the six burn diagnosis-related groups (DRGs) to explain variation in patients' length of stay was 20% and their ability to predict total costs was 24%. For the same patient population, the explanatory power of the DRGs improved to 54% for length of stay and 44% for costs when these variables were adjusted by the Severity of Illness Index. We also investigated whether hospitals with burn centers treated a more severely ill population of patients with burns than did hospitals without such centers. Significantly higher levels of severely ill patients with burns (p less than or equal to 0.0001) were found at burn center hospitals. Other patients or treatment variables, combined with a case-mix severity measure, were evaluated for their ability to further increase the explanatory power of DRGs. We also discuss here the use of the study results for reevaluating reimbursement policy.