Updated research request forms and data security approval requirement effective 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
There are many different provider variables in the Medicare Fee-for-Service (FFS) Claims and Encounter data. Researchers are often interested in the performing NPI and/or the facility CCN or organizational NPI, but other variables are sometimes…
Claims for ambulance services are found in both the Carrier and the Outpatient claims data. This article describes how to identify ambulance services.
Part D Event (PDE) files for data years prior to 2010 may include the values of “XX” or “NA” for any of the four Utilization Management variables. This article describes when and why each value was used.
With the exception of PY 2014, CMS research files do not include beneficiary risk adjustment scores. However, CMS does provide the programming code and instructions to calculate the three risk adjustments that CMS uses as the basis for managed care payment.
Cost report variables are split between two data files depending on the format of the variable. A master table lists all cost report variables and the format. The “Usage” column in the master table specifies the format of the variable, which determines the file location.
Beginning in 2008, some hospital provider numbers appearing in the claims contain a “V” in the fifth position of the six-digit Medicare Provider Number. Usually, the fifth position is a number, not a character. These hospital provider numbers appear in the MedPAR, Inpatient and Outpatient files for both RIF and LDS versions. ResDAC recommends that researchers remove these claims.
CMS updated several Medicare cost report forms. As a result, during the year of the transition and up to one year after, the facility will have two separate data downloads, one that includes all the data collected under the old form and another one under the new form.
The Medicare cost report files are created by Fiscal Year. The definition used to create the fiscal year files vary depending on the provider type.
When importing Medicare cost reports into Microsoft Access, data users should use the “link specifications” option to ensure that each variable imports with the correct data type.
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.
Occasionally researchers need to obtain identifiable data for MCBS participants, including claims data outside MCBS participation (i.e. before or after the individual participates in the MCBS). This article provides a brief overview of that process.
This article provides a brief overview of the SEER-Medicare linked database.
This article outlines the availability of date of service information for the Limited Data Set (LDS) Medicare claims files.