Inpatient Definitions and Methodology

Key Attending Physicians

The data in this report are taken from the CMS Medicare Standard Analytical File (SAF) for hospital IPPS claims during a recent 12 month period and are consistent with CMS Data Release policies. Because of these policies, only physicians and MS-DRGs with more than 10 patients during the period are reported.

The attending physician for each patient is identified by NPI number in the SAF. Physician names and other FOIA-disclosable data information are taken from the National Plan and Provider Enumeration System (NPPES).


The National Plan and Provider Enumeration System (NPPES) contains FOIA-disclosable data for health care providers. These data include Provider Name and other identifying information.


The number of IPPS claims for a physician. IPPS claims are Medicare fee-for-service inpatient claims paid under the Inpatient Prospective Payment System (IPPS).


The total payment is the amount paid to the hospital for a physician’s patients. This amount does not include any capital pass-thru amount or organ acquisition amount. It includes payments by Medicare (i.e. base MS-DRG payment, outlier payment, disproportionate share adjustment (DSH), indirect medical expense adjustments (IME), adjustments for certain transfers, etc.) It also includes amounts paid by or on behalf of the patient (e.g. deductibles or coinsurance) and amounts paid by third party insurers.


The total cost to the hospital for a physician’s patients. 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 case mix index is the average relative weight for all of a physician’s patients. MS-DRGs at lower severity levels have lower relative weights and MS-DRGs at higher severity levels have higher relative weights. The CMI provides an index of patient mix among levels of severity for a physician’s patients.