Fact sheet

Medicaid and CHIP T-MSIS Analytic Files Data Release

Medicaid and CHIP T-MSIS Analytic Files Data Release

Given the primary role that Medicaid and the Children’s Health Insurance Program (CHIP) play in our nation’s health care system, the Centers for Medicare & Medicaid (CMS) has made significant investments in these programs’ information technology and data analytic infrastructure. These investments are designed to improve access to high-quality, timely Medicaid and CHIP data to ensure robust monitoring and oversight of these vital programs that cover nearly 73 million Americans.  The lack of access to high quality, timely Medicaid and CHIP data is a concern of CMS, the Government Accountability Office (GAO) and other oversight entities that routinely highlight this issue in their reports. To address this problem, CMS has been working with states since 2011 to implement changes to the data collected about beneficiaries and providers, fee-for-service and managed care claims, and managed care plans and liable third parties, better enabling data-driven decision-making for Medicaid and CHIPThe Transformed Medicaid Statistical Information System (T-MSIS) initiative transitions state reporting from the legacy Medicaid Statistical Information System (MSIS) to a timelier and expanded data set using a modernized technology platform to collect Medicaid and CHIP data from states. Because of the size and complexity of T-MSIS files and the frequency of updates, the raw T-MSIS data are challenging to use directly for analytic purposes. Therefore, CMS has created a series of data sets optimized for analytics, known as the T-MSIS Analytic Files (TAF) consisting of research identifiable files (RIFs). 

What is T-MSIS Data?

T-MSIS enhances the way CMS collects operational data by standardizing definitions, adding data quality enhancements, and improving the timeliness of data submission by moving from quarterly to monthly data submissions. In addition, T-MSIS provides a more comprehensive and robust set of data files and data elements which include:

  • Enhanced information about Medicaid and CHIP beneficiary eligibility and enrollment
  • Fee-for-service claims and managed care service use and spending data
  • Managed care plan and provider information (in a future release)

Using T-MSIS data, CMS has developed research-ready files, called TAF. The TAF consist of research identifiable files (RIFs) with beneficiary-level data that are available with an approved Data Use Agreement. The TAF RIFs include data from calendar years 2014, 2015, and 2016, and will be used by CMS, oversight entities and researchers to answer key questions about the Medicaid and CHIP programs.

To support use of the TAF, CMS is also releasing supplemental state-level data quality briefs and technical documentation that further explain the files and state data.

What is included in this release and who will use it?

For the first time, CMS is releasing a robust set of research-ready T-MSIS data files and products, consisting of TAF RIFs and TAF user support materials.  User support materials include TAF Data Quality (DQ) briefs and snapshots and TAF Technical Guidance documents, among others. The TAF and supporting documentation will be used by CMS, oversight entities and researchers for program monitoring, oversight, evaluations and answering key questions about Medicaid and CHIP.


The TAF RIFs include annual files that contain demographic and eligibility information for all Medicaid and CHIP eligible beneficiaries as well as claims files that contain service use and payment records. Data shared with researchers will not include beneficiary names, addresses, or phone numbers, in order to protect beneficiary privacy, and proprietary managed care payment information will be redacted. A total of five file types are being released for calendar years 2014, 2015 and 2016 at this time:

  • Annual Demographics and Eligibility (DE) File
  • Inpatient Hospital (IP) Claims File
  • Long-Term Care (LT) Claims File
  • Pharmacy (RX) Claims File
  • Other Services (OT) Claims File

TAF User Support Materials

CMS created several resources to support researchers in their use of the TAF RIF, including technical guidance and a robust portfolio of data quality products to assist TAF users and potential TAF users in assessing the accuracy, reliability and usability of the files.

  • CMS has produced a series of 35 TAF DQ briefs that assess and summarize at a high level the reliability, accuracy, and usability of 2016 TAF data.  The DQ snapshots provide topical and state-specific views of these data quality assessments.  This summary DQ information is available for calendar year 2016 only, the most recent year of data in this release.
  • TAF Technical Guidance Documents provide detailed instructions on how to use the data for analysis.
  • Introductory materials are available to help end users of the data get started quickly, which include:
    • an introduction to TAF presentation
    • a crosswalk that provides TAF analogs to Medicaid Analytic eXtract (MAX) user support materials
    • TAF availability chart outlining when states are included in TAF, based on their T-MSIS cutover date
  • All supporting technical documentation can be found through, and the TAF DQ briefs and snapshots are available on

CMS-produced Reports Using TAF Data

CMS published de-identified state-level per capita expenditures for calendar year 2017 as part of the 2019 fall release of the Medicaid and CHIP Scorecard for those states where data quality assessments established that the data were of sufficient quality to make the calculation possible.  CMS also published the results of the data quality assessments for all states on the Scorecard.

As part of the 2019 fall release of the Medicaid and CHIP Scorecard, CMS will publish de-identified average annual Medicaid expenditures per enrollee for calendar year 2017 per state for five eligibility groups: children; adults ages 65 and older; people with disabilities; and Medicaid expansion adults (i.e. Group VIII). These estimates will be available for those states where data quality assessments made the calculation possible, and the estimates rely on total spending reported by states to the Medicaid Budget and Expenditure System and the number of enrollees and their expenditures reported by states in T-MSIS.  Additionally, CMS will publish the results of the data quality assessments for all states on the Scorecard which can be found here:

On October 24, 2019, CMS released the T-MSIS Substance Use Disorder (SUD) Data Book pursuant to section 1015(a) of the Substance-Use Disorder Prevention that Promotes Opioid Recovery and Treatment (SUPPORT) for Patients and Communities Act (P.L. 115-271).  The SUD Data Book is a publicly available compendium using preliminary TAF data, including data on the number of beneficiaries ages 12 and older who were enrolled in Medicaid for at least one day in 2017 and received full or comprehensive benefits.

How is CMS addressing T-MSIS data quality issues?

Over the last year, CMS has been working with each state to improve the quality and completeness of its T-MSIS submissions and will continue to do so throughout 2019 and 2020. Missing data is one data quality measure CMS actively monitors and works with states to improve and correct. CMS has prioritized 12 top priority items related to T-MSIS data quality. States have made significant progress in addressing these items, and these areas were selected because they have the greatest impact on using T-MSIS data for reporting and analysis.  In 2019, CMS expanded these top priority items to an additional 11 focus areas. Moving forward, this work will continue to expand to additional top priority areas and, with the release and use of the T-MSIS data by CMS and others, CMS expects the quality of the T-MSIS data to improve over time.

How do researchers and external partners obtain access to TAF RIF?

All external researchers who want to obtain access to the TAF RIF should contact the CMS Research Data Assistance Center (ResDAC). ResDAC staff will work with the researcher to identify the CMS data files available to conduct his/her study and assist with completing the forms needed for the request package.  Researchers who are approved for access to the TAF will be required to sign a CMS data use agreement that contains strict beneficiary privacy and data security requirements.  To learn more, visit the ResDAC website at:  

What’s next?

Additional research-ready TAF RIFs with data for 2017 and 2018 are expected to be released sometime in 2020. A future release will include annual files containing information on providers and managed care plans.

CMS’s releases of the SUD Data Book, TAF RIFs and guidance documentation, and the Medicaid and CHIP Scorecard are major steps towards ensuring robust monitoring and oversight of Medicaid and CHIP. By using these Medicaid and CHIP data, CMS, states and researchers will help drive smarter spending and better health outcomes for Medicaid and CHIP beneficiaries.