Enrollment Source

SAS Name

This variable indicates the source of enrollment data.


The Centers for Medicare & Medicaid Services (CMS) has updated the Medicare enrollment source data for the Master Beneficiary Summary File (MBSF). As of March 2017, the MBSF includes Medicare enrollment information from the CMS Common Medicare Environment (CME) rather than the Enrollment Database (EDB). Data from the two sources was nearly identical. The CME improves the identification of Medicare Part B enrollment and also allows for more timely release of the MBSF.

The universe of beneficiaries in the CME versus the EDB version of the MBSF are only slightly different.

Source: CCW

ResDAC Comments

From CY 2017 to CY 2021, the MBSF: Chronic Conditions segment also has a newer (CC30) version. This variable is not available in the CC30 version.

Code Code value
EDB Enrollment Database
CME Common Medicare Environment