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Medicaid and CHIP Payment and Access Commission
MACPAC > Program Administration > Medicaid administrative data

Medicaid administrative data

Published On

January 15, 2021

Data on Medicaid and CHIP play a key role in answering policy questions that affect program enrollees, states, the federal government, providers, and others, and in ensuring accountability for taxpayer dollars. In the course of administering the programs, states and the federal government receive and generate large amounts of data that include state plans and waiver documents, eligibility information, claims that document services provided, and state accounting statements submitted quarterly for the purpose of claiming federal funds.

The timeliness, quality, and availability of federal administrative data is of particular concern. Such data are meant to provide comparable information across states, which maintain their own data systems. They are also key to providing a national picture of the Medicaid and CHIP programs.

State data systems

All states maintain comprehensive and detailed data on their individual Medicaid and CHIP programs, and are statutorily required to maintain a Medicaid Management Information System (MMIS) to process claims from providers and to perform a variety of information retrieval and reporting functions (Section 1900(r) of the Social Security Act). However, each state’s MMIS reflects its own administrative structures and processes, even when multiple states contract with the same private vendor for MMIS support. In addition, MMIS and other data are often housed in multiple systems that are fragmented within states and in formats that limit their comparability across states. Issues include:

  • Unique billing codes. Some states create state-specific billing codes for certain services. This is particularly an issue for services that are unique to Medicaid, such as long-term services and supports provided in home and community-based settings.
  • Payments not based on claims. Not all payments to providers are processed through a state’s MMIS. Examples may include: retrospective settlement amounts for providers who are paid on the basis of costs, rather than a fee schedule: supplemental payments to providers made under various statutory authorities; and payments to certain public providers who receive funding through state or local budget processes, sometimes in lieu of direct payments by the state Medicaid agency.
  • Eligibility data coming from different systems. Although federal law requires states to operate their programs under the authority of a single state agency, multiple state and local government entities may have responsibility for different program functions. State MMISs typically receive and store data extracts containing eligibility-related information to ensure that payments are made only to current Medicaid and CHIP enrollees. However, state eligibility systems operate separately and distinctly from MMISs, in part because they may be used to enroll individuals in other public programs.

States that use managed care also obtain encounter data from plans. These can be used for a variety of purposes that include setting capitation rates for plans, calculating performance measures, and generating ad hoc reports for state agencies, legislatures, and external constituencies. Historically these data were underreported by states (OIG 2009) and their quality and completeness at the federal level went largely unexamined (Byrd and Verdier 2011). The federal government is now beginning to examine these data. For more information on MACPAC’s work with encounter data, see the MACPAC staff presentation from the April 2014 public meeting, Evaluating Medicaid Managed Care Encounter Data for Policy Analysis.

Federal administrative data systems

At the federal level, most administrative data on Medicaid and CHIP consist of information reported by states to the Centers for Medicare & Medicaid Services (CMS) on their program policies, the characteristics and service use of their enrollees, and their program spending. Key sources include:

  • Medicaid and CHIP Budget and Expenditure System (MBES/CBES): Reports (forms CMS-64, CMS-21, and CMS-37) detailing aggregate spending that are submitted by states to receive federal reimbursement for a share of their Medicaid and CHIP spending.
  • Medicaid Statistical Information System (MSIS): Demographic and enrollment-related information on each person enrolled in Medicaid, and, at state option, separate CHIP programs, as well as a record of each claim paid for most services an enrollee receives.
  • Statistical Enrollment Data System (SEDS): Aggregate statistics on CHIP and child Medicaid enrollment.
  • Form CMS-416: Aggregate statistics on children receiving Early and Periodic Screening, Diagnostic, and Treatment (EPSDT) services.
  • Form CMS-372: Aggregate statistics on enrollment and spending under home and community-based services waivers.
  • Medicaid Drug Rebate System (MDR): Aggregate statistics on drug utilization and payments, used for calculating rebates to states from drug manufacturers.
  • State Medicare Modernization Act (MMA) files: Monthly eligibility-related information on individuals dually enrolled in Medicaid and Medicare, used for Medicare Part D purposes.
  • State plan documents: Documents that describe a state’s Medicaid and CHIP policies under regular state plan (i.e., non-waiver) rules.
  • Waiver documents: Documents that describe a state’s Medicaid and CHIP waiver programs including those operating under Section 1115, 1915(b) and 1915(c) authorities.
  • Medicaid Managed Care Data Collection System(MMCDCS): Aggregate statistics on managed care enrollment, along with basic descriptive information on each managed care plan and program within a state.
  • CHIP Annual Report Template System (CARTS): Information on CHIP programs, such as policies on eligibility and cost sharing, as well as performance measures regarding receipt of care.

For more information on these data sources, see MACPAC’s March 2011 report chapter, Improving Medicaid and CHIP Data for Policy Analysis.

Recent federal efforts to improve data timeliness, quality, and availability

CMS has a number of major activities underway to improve Medicaid and CHIP data. These include MACPro, a web-based system designed to collect state plan, waiver, and other programmatic documents in a structured and consistent format. The second is the Transformed Medicaid Statistical Information System (T-MSIS) which builds on existing person-level and claims-level MSIS data submitted by the states. CMS is also using its ongoing Medicaid Information Technology Architecture (MITA) initiative to establish national guidelines and standards for state-operated Medicaid and CHIP data systems that are funded with federal dollars. MACPAC described and commented on these efforts in its June 2013 report chapter, Update on Medicaid and CHIP Data for Policy Analysis and Program Accountability.