Tech Notes: Data Sources

Medicare Population Data
In March of each year, Medical Review of North Carolina, Inc. (MRNC) receives a data file containing information on beneficiaries enrolled in Medicare who resided in NC for the previous year. These data are provided from the beneficiary enrollment database supplied to MRNC by the Centers for Medicare & Medicaid Services (CMS).

Hospital Discharge Data
Hospital discharge data are based on claims submitted for payment to Medicare. MRNC receives all claims data for beneficiaries residing in North Carolina from CMS in the form of the NC Health Service Encounter File. While this file is updated monthly at MRNC, the data provided on this web site are updated quarterly (every March, June, September, and December) to reflect claims that have been finalized in the preceding months.

Influenza Immunization Data
Flu immunization data are based on claims submitted for payment by Medicare. MRNC receives annual flu immunization claim files from state-specific CMS files with one or more paid claims for flu immunizations administered from September through December of the given year and processed through March of the following year. The number of eligible beneficiaries is provided from the beneficiary enrollment database supplied to MRNC by CMS.