Data Dictionaries & File Layouts

The SDRC Team offers state Medicaid agencies advice on how to use Medicare data for Medicare-Medicaid care coordination and program integrity activities. In addition to this advice, the following external websites can provide state Medicaid agencies with detailed information on the variables and layouts of Medicare data:

CCW Data 

The Chronic Condition Data Warehouse (CCW) provides information on Medicare Parts A & B and Assessments (MDS, OASIS, Swing Bed, and IRF-PAI) data.


Enhancements to the CCW 

The CCW contains Medicare and Medicaid claims, eligibility, and enrollment data. The CCW also contains indicators (i.e., “flags”) for 27 chronic conditions, which were originally chosen based on their high prevalence among elderly Medicare-only beneficiaries. Medicare-Medicaid Coordination Office (MMCO) has expanded these flags for all years of existing data (2000-2008) to include the following: 1) the Medicaid-only population; 2) identification of individuals among the dually eligible population with the original 27 conditions for both Medicare and Medicaid claims: rather than solely their Medicare experience; and 3) additional flags for all 3 populations with conditions that are known to affect dually eligible population with disabilities and Medicaid-only beneficiaries. MMCO developed and has made available CCW flags for 9 mental health conditions, tobacco use, and 15 conditions related to intellectual, developmental, and physical disability with the assistance of subject matter experts.

Coordination of Benefits Agreement (COBA) Companion Guides

Benefits Coordination Recovery Center’s COBA HIPAA 5010 Companion Guide provides information for preparing and testing HIPAA 5010 COBA transactions. This guide provides information in understanding what values will appear in various fields on the outbound 837 claims. The Washington Publishing Company provides the HIPAA 5010 837-I and 837-P Technical Report Version 3 (TR-3) Guides. These comprehensive guides fully lay out the rules for HIPAA implementation of the 837 claims. There is a charge for these consolidated guides through the Washington Publishing Company.

Medicare-Medicaid Linked Enrollee Analytic Data Source (MMLEADS) Version 2.0 

MMLEADS is a suite of 2006-2012 linked data files for Medicare-Medicaid eligibility, enrollment, utilization, and expenditure data. This data source includes healthcare information for all dual-eligible Medicare-Medicaid enrollees, and, for comparison purposes, all Medicare-only beneficiaries and Medicaid-only beneficiaries with disabilities. MMLEADS provides utilization and expenditure metrics based on MMCO’s preferred method of identifying dually eligible population (e.g., from the monthly “State MMA File”), while also keeping the flexibility to generate metrics according to other user-defined criteria. MMLEADS contains a linking variable for linking to other data (e.g., survey, assessment, claims) that are housed in the CCW.

SDRC Tip Sheet – Public Use Files (PUF) 

This tip sheet contains a list of free, publicly available data files that include Medicare and Medicaid services at the beneficiary and provider levels, data by state, and data file guides.


The MMLEADS Public Use File (PUF) data are based off MMLEADS, version 2.0. The 2006-2012 aggregated data include information on full and partial dually eligible population, as well as Medicare only enrollees and Medicaid only (eligible via disability) enrollees for comparison purposes. The MMLEADS PUF data and User Guide are available for download.

State-CMS File Exchanges

Since 2005, state Medicaid agencies have been submitting files at least monthly to CMS to identify all dually eligible beneficiaries. This includes full-benefit dual-eligible beneficiaries and partial-benefit dually eligible beneficiaries (i.e., those who get Medicaid help with Medicare premiums, and often for cost-sharing). The file is called the “MMA File” (after the Medicare Prescription Drug, Improvement, and Modernization Act of 2003), but is occasionally referred to as the “State Phasedown File.”

The Medicare Advantage Prescription Drug (MAPD) State User Guide has additional information pertinent to the content of multiple monthly files. To access the user guide, download the following document: MAPD State User Guide.

Medicare Modernization Act (MMA) File 

State Medicaid agencies (“state”) submit files on dually eligible beneficiaries and partial benefit dually eligible beneficiaries (i.e., those who get Medicaid help with Medicare premiums and often for cost-sharing) to CMS every month. These files are called “MMA Files” or “State Phasedown Files.” Each state sends at least one MMA File (i.e., Request File) to CMS monthly. More information about MMA Request File Submissions can be found here.

MMA Request Files contain beneficiary names, demographics and information on beneficiary Low-Income Subsidy enrollment, institutionalization, and Medicaid and Medicare eligibility status. Beneficiary names and demographic information are used to perform matches between the state beneficiary records and the CMS Medicare Beneficiary Database. CMS automatically returns an MMA Response File to the state upon the successful processing of the MMA Request File. MMA Response Files include a copy of the MMA Request File detail record, error return codes, data from the CMS Medicare Beneficiary Database, a summary of record validation and matching outcomes, and count by month for each month of enrollment information on the MMA Request File. For more information on MMA files, please refer to Sections 4-7 of the MAPD State User Guide.

Territory Beneficiary Query (TBQ) File 

The TBQ process is a data exchange between CMS and the state Medicaid agencies to determine dual status eligibility and enrollment information as part of the process for Low Income Subsidy enrollment. State Medicaid agencies can submit TBQ Request Files to obtain batch data submitted through the MMA files, as described above. The TBQ Response Files contain beneficiary names and demographic information. CMS automatically returns a TBQ Response File, which contains beneficiary names, residence addresses, demographic information, and entitlement information for each TBQ Request File. For more information on TBQ files, please refer to Section 11.3 of the MAPD State User Guide.

State Medicaid agencies can also download the following data documentation:

Prescription Drug Event (PDE) File Layout 

The PDE File Layout spreadsheet describes both the structure and variables contained within PDE files.

Part D Netting Explanation 

The Part D Netting Explanation document explains the data elements that CMS has developed to enable PDE users to identify and net unique prescription drug claims.

Integrating Monthly Files into Part D Final Action 

The Integrating Monthly Files into Part D Final Action document explains the additional steps necessary to identify final action records within the PDE data when incorporating the monthly update files.

Need additional help or information on this process?