Updated research request forms and data security approval required beginning 4/24/23
Knowledgebase
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…
Popular
Articles
This article provides guidance on how to identify hospital emergency room claims from the Medicare files.
Providers that bill Medicare use codes for patient diagnoses and codes for care, equipment, and medications provided. This articles provides resources to identify the codes…
To describe the CMS cell size suppression policy and provide examples of common scenarios and possible options.
Featured Article
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…
Detailed information about Medicare Part D drug plan formularies is available in two CMS data files. Important differences in the files are outlined below, including whether or not the files can be linked to other data sources.
The Medicare Hospital Service Area File is one of the few CMS non-identifiable files that can be opened in Microsoft Excel. The article describes the steps to import the file into Excel.
A number of CMS Limited Data Set (LDS) files are released first as a Proposed Rule file and then as a Final Rule file. This article provides a brief description of the differences between those two files.
The purpose of this article is to describe what ambulatory surgical centers are and to explain how this provider type differs from other provider types that bill Medicare.
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:
Medicare managed care enrollment has fluctuated over the years and is a frequently requested statistic. Often researchers are interested in penetration rates or the percentage of Medicare beneficiaries enrolled in a Medicare managed care plan. These plans are also referred to as Medicare Part C, Medicare Advantage (MA), or Medicare Health Maintenance Organizations (HMOs).
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 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 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 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.
Researchers who request the Minimum Data Set (MDS) from CMS will need to determine whether they would like data based on Target Date or Submission Date. This article provides definitions for Target and Submission dates and examples for when each selection is useful.
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.