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 the structure of the Medicare cost reports and provides instructions for identifying specific data elements for specific facilities. While the examples and screenshots provided below are specific to the hospital cost reports, the discussion on file structure and logic used for identifying specific variables are applicable to any facility cost report. 
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.
The purpose of this knowledge base article is to 1) present an overview of International Classification of Disease (ICD) codes and versions available, 2) describe where researchers can find these codes in the Medicare claims, and 3) understand how ICD codes appear in the data.
This article is designed to provide a brief overview of the differences between the Medicare Current Beneficiary Survey (MCBS) Public Use File (PUF) and MCBS Limited Data Set (LDS) files so researchers can decide which file is appropriate for their study needs.
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.
Provide the steps to identify the drug name from the RxNorm database for the NDCs in the BSA PDE PUF. 
To provide estimated file sizes for recent, commonly requested 5% and 100% Research Identifiable Files.
Researchers working with the Research Identifiable (RIF) MedPAR or Inpatient and Skilled Nursing Facility (SNF) claims may find records that do not appear to correspond to the year of the file. This article explains these instances. 
Researchers who are interested in studying Part D utilization within the Medicare Current Beneficiary Survey (MCBS) can do so by using the MCBS Cost and Use for years 2006 through 2013. This article provides an overview of where Part D utilization information located within the MCBS during these years, as well as the list of PDE variables included with the file.
This article describes the difference between two similiar variables in the carrier file -the Line NCH Payment Amount and Line Provider Payment Amount.
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.