Inpatient Definitions and Methodology

Statistics for the Top 20 DRGs

All information in this report is taken from the Medicare Provider Analysis and Review (MedPAR) file which is updated annually by CMS based on the federal fiscal year.  The file includes billing data for 100% of all Medicare fee-for-service claims for discharges during the twelve months ending September 30.  The report is based on the most recent period available and is consistent with CMS Data Release policies. Please note that a new MS-DRG patient classification system was introduced in FY 2008. This system replaced the prior DRG definitions and is no longer compatible with the DRGs reported here.

The twenty DRGs with the highest numbers of discharges are ranked by volume and all other DRGs are summarized:

Number of Medicare Discharges
total number of IPPS claims for the DRG.
Average Length of Stay
total patient days divided by the number of discharges.
Average Charges
total gross charges divided by the number of discharges
Average Reimbursed
Medicare Reimbursement is the amount paid to the hospital and/or patient by Medicare for the services reported on a bill. This amount does not include any capital pass-thru amount or organ acquisition amount. In addition, it excludes amounts paid by or on behalf of the patient (e.g. deductibles or coinsurance).  The average reported for a DRG is total Medicare reimbursement divided by the number of discharges.
Average Cost
Costs are calculated for each patient on the basis of ratios of costs to charges for routine services and ancillary areas. Click here for cost allocation methodology.  The average reported for a DRG is total allocated cost divided by the number of discharges.

A brief description of the Medicare Prospective Payment System is provided to explain the system, DRGs, the case mix index, etc.