ENROLLMENT DATABASE FILES

The EDB is the current CMS (previously HCFA) repository of enrollment and entitlement data for persons who are or have ever been enrolled in Medicare.

Enrollment Database (EDB)

The EDB contains current and historical Medicare enrollment and entitlement information for all beneficiaries ever enrolled in the Hospital Insurance (HI) or Supplementary Medical Insurance (SMI) Medicare programs. The EDB replaced the Health Insurance Master (HIMA) File as the designated CMS repository of enrollment and entitlement data. As the primary source of information on demographic characteristics and geographic distribution of the entire Medicare population, the EDB supports various CMS and external research applications. Program and policy analysts, as well as other researchers in health care related fields, use the personal identifiers present on EDB records to construct samples and link data from a variety of sources at the beneficiary level. Analytic files derived from the EDB are used by CMS to support program reporting requirements such as the production of statistical profiles of the Medicare population.

File Creation

Beneficiaries are enrolled in Medicare based on criteria defined in Title XVIII of the Social Security Act of 1965 and subsequent amendments to the Act. EDB records are generated by the entitlement and enrollment of beneficiaries in the Medicare program. The Social Security Administration (SSA) maintains demographic and entitlement information on all Medicare beneficiaries for whom entitlement is derived from Old Age and Survivors Insurance, disability insurance, End Stage Renal Disease (ESRD) programs, and the Railroad Retirement Board (RRB). The SSA Master Beneficiary Record (MBR) is the primary source of data for the EDB. Beneficiary demographic characteristics, dates of enrollment and termination, cross-reference claim numbers, changes of address, and all other data contained in the SSA MBR system are transmitted from SSA to CMS to update the EDB. Additional information on RRB beneficiaries is contained on a beneficiary master record maintained by the RRB. Although entitlement data from the EDB typically update the Common Work File (CWF), a small number of data elements from the CWF update the EDB, such as some dates of death and Medicare secondary payer information. The EDB was implemented in 1991. Currently, the EDB contains records for all Medicare beneficiaries ever entitled to HI or SMI. As such, creation of the EDB is a continuous process, with records of past enrollees kept in the database while new records are added as new cohorts of beneficiaries enroll. A flat file version of the EDB, called the Unloaded EDB (UEDB), is created each month. The UEDB is a complete write-off of the EDB.

File Maintenance

The EDB is updated daily with information received primarily from SSA, RRB, CWF host sites, and CMS clerical staff at central and regional offices. Direct online updates are performed interactively through the Enrollment Retrieval New Interactive Edit (ERNIE) System by authorized staff nationwide. Transaction updates received from SSA, RRB, and the CWF host sites are performed through the Medicare Update Processors for Enrollment Transactions (MUPPET) System. SSA and CWF data are subject to Quality Assurance (QA) checks including format, range, and logical consistency edits before they are used to update the EDB. The format edits verify, for example, that numeric fields contain numeric data. The range edits verify that a field contains expected data (e.g., a field in which the valid range is 0, 1, or 2 is not filled with any other digit). The logical consistency edits verify, for example, that the termination date is later than the entitlement date. Any inconsistencies are flagged for review and correction.

File Structure and Usage

The EDB contains information for each beneficiary ever enrolled in the Medicare program, regardless of whether he or she is currently designated as "inactive" or "active." An inactive beneficiary is one who has a valid date of death at least six months in the past and has had no activity for at least six months. All other beneficiaries are deemed active. Currently, the EDB includes two types of records: full and skeleton. Full records include detailed personal identifiers and eligibility and entitlement status information for all active beneficiaries and some inactive beneficiaries. Skeleton records include beneficiary identification information without entitlement or enrollment data for those inactive beneficiaries who do not have full records on the EDB. At one time, full records were regularly reduced to skeleton records for inactive beneficiaries, and the complete information was maintained separately at the HCFA Data Center (HDC). In 1994, the EDB was populated with all the data from the inactive file. There are approximately 12 million skeleton records, whose complete information was not available, remaining on the EDB. The EDB is an M204 database designed to support CMS Medicare entitlement and enrollment functions. It is primarily an operational database that establishes the authoritative entitlement for Medicare beneficiaries and supports the claims payment process at the CWF host sites nationwide. The EDB records are the single source of Medicare and MCO enrollment information at the CWF host sites. As a source of information on demographic characteristics and geographic distribution of the entire Medicare population, the EDB supports a variety of research applications. The Medicare population statistics generated from enrollment records are widely used to support policy decisions. Program and policy analysts, as well as researchers in various health care related fields, use the personal identifiers present on EDB records to construct samples and link data from various sources at the beneficiary level. The EDB information supports identification and sampling of beneficiary cohorts with particular demographic characteristics.

Data Structure and Usage

The EDB provides detailed information on the entitlement and enrollment status of each beneficiary. As of February 1997, the database contained data on approximately 80 million beneficiaries. Approximately 150,000 new beneficiaries are accredited to the EDB each month. The EDB contains approximately 120 data elements. These elements capture personal identifiers such as name, Social Security Number (SSN), and Health Insurance Claim (HIC) number; and detailed demographic data such as date of birth and death, sex, and race. In addition to personal identifiers and demographic characteristics, the EDB contains entitlement and payer information. Entitlement information includes Part A and Part B entitlement status, and start and termination dates. Payer information includes premium payer identification information, an indicator for primary payer other than Medicare, and a GHP enrollment indicator. Information regarding changes over time to many of the data elements is also included.

Methods of Access

The EDB is maintained as an M204 database at the HDC. EDB data can be accessed through the EDB Workbench (EDBW) or Decision Support Access Facility (DSAF) by authorized HDC users. Quarterly UEDB Files are maintained for 30 months at the HDC and can be accessed by authorized HDC users. Six monthly UEDB files are retained (i.e., two full quarters). The EDBW is a menu-driven retrieval system for creating customized output files (user views) from the EDB. The most common EDBW access is made using a predefined list of identification numbers such as SSN or HIC number. When the search criterion is SSN, EDBW returns data for all family members associated with the SSN. When a HIC number is used, EDBW returns data for individuals matching the HIC number directly. If no direct matches are found, EDBW returns matches made through Beneficiary Identification Code (BIC) equatability, or through cross-reference or SSN matches. A more flexible retrieval method is available using match criteria to keyed EDB elements (e.g., birth dates before a specified date, Part A entitlement in a given year, or no MCO enrollment for a given time period). CMS staff must be contacted to help generate criteria used by EDBW. Decision Support Access Facility (DSAF) is a menu-driven system for retrieving data from a variety of claims, utilization, and enrollment files or databases including the EDB. DSAF provides access to current and historic Medicare claims, as well as enrollment and entitlement data. Data can be selected based on HIC number, specific data field combinations, or a specified percentage of records.

Migration of Data

The EDB now contains data that was formerly housed in the Billing and Collection Master (HJBCM) file. In the future, additional beneficiary enrollment and eligibility data that are currently maintained in the TPEARTH Master File will be included in the EDB. Currently, the EDB contains a state buy-in indicator that signifies a record on the TPEARTH Master File and all GHP enrollment periods.

List of Data Elements

A list of the EDB data elements that are available via the EDBW, and brief definitions and coding schemes, will be included in the future on the CMS web site at www.cms.hhs.gov.

Enrollment and Eligibility Introduction | Enrollment Database | Other Enrollment Files