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…
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.
CMS began offering quarterly claims and enrollment data with Quarter 3, 2015. This article describes the quarterly data file creation, availability, and pricing.
Researchers may now request Research Identifiable File (RIF) Medicare data on a quarterly basis, in addition to the annual files.Data available on a quarterly basis includes FFS claims (Inpatient, Outpatient, Home Health Agency, Hospice, Skilled Nursing Facility, Carrier, and Durable Medical Equipment) and the Master Beneficiary Summary File: Base A/B segment.
To provide estimated file sizes for recent, commonly requested 5% and 100% Research Identifiable Files.
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.
This article provides a link and overview of the document on finder and crosswalk files written by the CMS data distributor, HealthAPT.
This article provides resources for obtaining statistics and reports related to the Medicare and Medicaid programs and their beneficiaries. The following Medicare/Medicaid statistical and summary data resources address some of the most common requests for this type of information. These are by no means exhaustive.
The beneficiary eligibility and enrollment files have changed in content and name over the years. It is important to understand the timing of these changes and the unique features of each file if you are using older files or see them referenced in articles.
Beneficiary death information is available in several of the Medicare enrollment files. Limited death information is also found in other files, such as the MedPAR. This article describes the variables found in each.
The purpose of this article is to describe how to use the Medicare managed care enrollment information found in the Medicare Beneficiary Summary File (MBSF) Research Identifiable File (RIF) or Denominator in the Limited Data Set (LDS). Medicare managed care is sometimes also called Medicare Advantage, Medicare Part C or Medicare + Choice.