Based on these criteria, we considered the RDRGs, AP-DRGs, and APR-DRGs to be the most promising refinements.
The Yale RDRGs were developed by the Health Systems Management Group at Yale University under a HCFA cooperative agreement.
The Yale RDRGs also recognize two special groups of cases: medical cases involving early death (within 2 days of admission) and cases requiring tracheostomy procedures.
Because the RDRGs represent a significant increase in the number of patient classes, several issues are raised:
The ability of the RDRGs to capture the difference in the amount of resources used to treat cases as severity increases.
Compared with the current Medicare DRGs, the Yale RDRGs result in a sizeable increase in the number of low-volume DRGs, and an even more significant increase in the number of DRGs with 30 or fewer cases.
For medical RDRGs, the relative weights of the "moderate" class of RDRGs are, on average, almost 40 percent higher than those for the "minor or no CC" class.
In addition, New York expanded the CC list by adding other diagnoses that are not considered catastrophic or major in the RDRGs based on the clinical judgment of medical staff.
Regarding the stability of the relative weights from year to year, the AP-DRGs are superior to RDRGs and improve on the Medicare DRGs, with only 23 percent of the AP-DRGs experiencing a greater-than-5-percent change in weight from year to year.