Knowledgebase

ResDAC has developed over 100 articles that cover topics ranging from the CMS data request process through using the data for a study. CMS has developed additional resources, including TAF data quality briefs and TAF data quality state snapshots, examining the quality of the Medicaid data.
Introductory
Articles
CMS offers files from aggregate data to individual person level data. This article describes the differences between the aggregate, public use files, the limited data sets,…
This article describes the Federal Regulations that govern the release of CMS data for research.
The purpose of this article is to identify 1) common strengths of Medicare and Medicaid administrative data and 2)  broad limitations for researchers to consider when…
To describe the CMS cell size suppression policy and provide examples of common scenarios and possible options.
States that have "Opted-In" to data sharing under the State Research request process are required to submit quarterly logs to CMS. 
The Centers for Medicare & Medicaid Services (CMS) seeks to ensure the protection of CMS data disclosed to external organizations for research purposes. To accomplish this, CMS has developed the Data Privacy Safeguard Program (DPSP). The DPSP reflects the CMS priorities to both improve data stewardship and to protect the privacy and security of CMS research identifiable files (RIF) that are made available for conducting important research studies.
To describe the CMS policy that prohibits non-US based researchers from accessing identifiable CMS data (RIF and LDS) and provide examples of common scenarios.
Along with claims at the individual beneficiary (single enrollee/provider/visit) level, state Medicaid programs also submit service tracking claims which record lump sum payments to providers or managed care plans. These data are a new enhancement to the TAF RIF, and researchers have the option of requesting these claims along with TAF claims data. This article describes service tracking claims in TAF RIF data and considerations for researchers.
The purpose of this article is to identify 1) common strengths of Medicare and Medicaid administrative data and 2)  broad limitations for researchers to consider when requesting and using the data.
For data years 2006 and forward, dually eligible Medicare beneficiaries are identified in the Medicare Master Beneficiary Summary File, Base segment. Initially available only as a RIF, this file was released as an LDS file in 2016. The monthly variable “Medicare-Medicaid Dual Eligibility” identifies dual status. Dual eligibles are also identified in the Medicaid Analytic Extract (MAX) Personal Summary (PS) file.
CMS must ensure that all research requests for identifiable (RIF) data have IRB documentation to satisfy the requirements of the Common Rule and the Health Insurance Portability and Accountability Act (HIPAA). This article describes the requirements and presents examples of acceptable IRB documentation. The IRB documentation must indicate that there was a review that satisfies the following two requirements:
This article describes three variable groups that can be used to identify managed care enrollment for Medicaid beneficiaries. Codes for the variables are also given that identify beneficiaries who received their comprehensive medical care under the Fee-For-Service (FFS) payment system.
This article summarizes two methods available to link mothers and their infants using the MAX data. Frequently researchers using the CMS Medicaid Analytic Extract (MAX) data are looking for ways to link mothers with their infants. Given the available identifiers in MAX data, there are two options.
This article provides resources for the assessment of the quantity and quality of managed care organization (MCO) encounter data in the Medicaid Analytic eXtract (MAX) files.
This article outlines the provider identification numbers that are available in the MAX files and options for linking to the Medicare Provider Number.