MAX files are available for calendar years 1999 through 2015. Files for 2013, 2014 and 2015, while in the MAX file format, may have been created using a combination of T-MSIS and MSIS data. These files are noted as MAX-T on the MAX TAF Availability Matrix (ZIP). Summary data and supporting documentation (SAS load statements, data dictionaries, record counts, anomaly tables, managed care crosswalks, and waiver crosswalks) are available through the links in the “Downloads” section below and the validation tables are available through the MAX Validation Reports page. Answers to some commonly asked questions about the MAX data can be found in the Frequently Asked Questions (PDF).
Each state’s Medicaid agency collects enrollment and claims data for persons enrolled in Medicaid and the Children’s Health Insurance Program (CHIP). These data are collected in the state’s Medicaid Management Information System (MMIS). Each state’s MMIS is tailored to the needs of that state’s Medicaid program. In partnership with the states, the federal government seeks to manage the Medicaid program and monitor the progress of the health care delivery system nationally. Because the Medicaid program varies by state, the data in the MMIS have historically been converted into a national standard and submitted to CMS via the Medicaid and CHIP Statistical Information System (MSIS). The Centers for Medicare & Medicaid Services (CMS) has made significant data collection advances in more recent years with the advent of the Transformed Medicaid Statistical Information System (T-MSIS).
The enrollment information in MAX identifies monthly enrollment after the retroactive/correction records have been applied and after certain state-specific data elements are transformed into a consistent, national format. The claims in MAX identify the services rendered and the cost of those services after the adjustments have been applied. The enrollment pertains to people enrolled in the given calendar year (CY), and claims pertain to the services rendered in that same time period, thereby making a consistent—and more meaningful—time period for analyses of enrollment, service utilization, and expenditures.
MAX Data Availability
Since the MAX data contain protected health information (PHI) and personally identifiable information (PII), they are protected under the Privacy Act. The data are available for approved research activities only through a Data Use Agreement (DUA) or Intra-/Interagency Agreement (IA) with CMS. Note that only approved academic research projects and certain government agencies are entitled to a DUA or IA to obtain MAX data. For help in preparing data requests (including DUAs), technical assistance with the data, or to report data problems, please contact the Research Data Assistance Center (ResDAC).
Please find notes and additional documented information about MAX data years 1999-2011 in MAX Data 1999-2011 (PDF).
In the MAX Data General Information zip files provided above, we include several supporting documents about MAX. A description and information about these supporting documents are provided here: MAX Data Zip File Supporting Documents (PDF).