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. 
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 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 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.
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.
To describe the CMS cell size suppression policy and provide examples of common scenarios and possible options.
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.
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.
Under changes to the Part 2 regulations on January 17, 2017, CMS is now permitted to include substance use disorder claims data in the Research Identifiable Files (RIFs).  Research Identifiable Files shipped or extracted in the VRDC after 05/22/2017 are no longer subject to the redaction.
Provide the steps to identify the drug name from the RxNorm database for the NDCs in the BSA PDE PUF.