Key points
- The National Center for Health Statistics (NCHS) Data Linkage Program links NCHS survey data with data from the Centers for Medicare & Medicaid Services (CMS).
- Linking NCHS data with CMS Medicare data files enables researchers to study changes in health and health care.
- Find a list of data dictionaries and resources for restricted-use data.

Overview
The National Center for Health Statistics (NCHS) Data Linkage Program provides restricted-use data files. Restricted-use NCHS-CMS Medicare Data can be accessed only through the NCHS Research Data Center (RDC) network.
Files linked to Medicare data files contain the following information—
- Program enrollment status
- Fee-for-service healthcare claims
- Medicare Advantage patient encounters
- Prescription drug events data
- Clinical assessments for patients residing in nursing homes or receiving home health care services
2014–2018
Master beneficiary summary
- Base (Part A/B/C/D) segment (01/29/2021)
- Chronic conditions segment (01/29/2021)
- Cost and utilization segment (01/26/2022)
Medicare Part D prescription drug event/drug characteristics
Medicare Part D Prescription Drug Event/Drug Characteristics File (01/26/2022)
Medicare provider analysis and review (MedPAR)
Medicare Provider Analysis and Review (MedPAR) File (01/26/2022)
Carrier
- Base Claim File (01/26/2022)
- Demonstration File (01/29/2021)
- Line Item File (01/26/2022)
Durable medical equipment (DME)
- Base Claim File (01/26/2022)
- Demonstration File (01/29/2021)
- Line Item File (01/26/2022)
Home health agency (HHA)
- Base Claim File (01/26/2022)
- Condition Code File (01/29/2021)
- Demonstration File (01/29/2021)
- Occurrence Code File (01/29/2021)
- Span Code File (01/29/2021)
- Value Code File (01/26/2022)
- Revenue Center File (01/29/2021)
Hospice
- Base Claim File (01/26/2022)
- Condition Code File (01/29/2021)
- Demonstration File (01/29/2021)
- Occurrence Code File (01/29/2021)
- Span Code File (01/29/2021)
- Value Code File (01/26/2022)
- Revenue Center File (01/26/2022)
Inpatient
- Base Claim File (01/26/2022)
- Condition Code File (01/29/2021)
- Demonstration File (01/29/2021)
- Occurrence code File (01/29/2021)
- Span code File (01/29/2021)
- Value code File (01/26/2022)
- Revenue Center File (01/26/2022)
Outpatient
- Base claim File (01/26/2022)
- Condition code File (01/29/2021)
- Demonstration File (01/29/2021)
- Occurrence Code File (01/29/2021)
- Span Code File (01/29/2021)
- Value Code File (01/26/2022)
- Revenue Center File (01/26/2022)
Skilled nursing facility (SNF)
- Base Claim File (01/26/2022)
- Condition Code File (01/29/2021)
- Demonstration File (01/29/2021)
- Occurrence Code File (01/29/2021)
- Span Code File (01/29/2021)
- Value Code File (01/26/2022)
- Revenue Center File (01/26/2022)
Carrier
- Base Claim File (01/29/2021)
- Line Item File (01/29/2021)
DME
- Base Claim File (01/29/2021)
- Line Item File (01/29/2021)
HHA
- Base Claim File (01/29/2021)
- Condition Code File (01/29/2021)
- Occurrence Code File (01/29/2021)
- Span Code File (01/29/2021)
- Value Code File (01/29/2021)
- Revenue Center File (01/29/2021)
Inpatient
- Base Claim File (01/29/2021)
- Condition Code File (01/29/2021)
- Occurrence Code File (01/29/2021)
- Span Code File (01/29/2021)
- Value Code File (01/29/2021)
- Revenue Center File (01/29/2021)
Outpatient
- Base Claim File (01/29/2021)
- Condition Code File (01/29/2021)
- Occurrence Code File (01/29/2021)
- Span Code File (01/29/2021)
- Value Code File (01/29/2021)
- Revenue Center File (01/29/2021)
SNF
- Base Claim File (01/29/2021)
- Condition Code File (01/29/2021)
- Occurrence Code File (01/29/2021)
- Span Code File (01/29/2021)
- Value Code File (01/29/2021)
- Revenue Center File (01/29/2021)
Home health outcome and assessment information set (OASIS)
- Assessment File (01/29/2021)
- Facility File (01/29/2021)
Long-term care minimum data set (MDS)
- Assessment File (01/29/2021)
- Facility File (01/29/2021)
1999–2013
Master beneficiary summary
- Part A/B segment (02/02/2017)
- Part D segment (02/02/2017)
- Chronic Conditions segment (02/02/2017)
- Cost and Utilization segment (02/02/2017)
Medicare Part D prescription drug event/drug characteristics
Medicare Part D Prescription Drug Event File (02/02/2017)
MedPAR
Medicare Provider Analysis and Review File (02/02/2017)
Carrier
- Base Claim File (02/02/2017)
- Line Items (02/02/2017)
DME
- Base Claim File (02/02/2017)
- Line Items (02/02/2017)
HHA
- Base Claim File (02/02/2017)
- Condition Code File (02/02/2017)
- Occurrence Code File (02/02/2017)
- Span Code File (02/02/2017)
- Value Code File (02/02/2017)
- Revenue Center File (02/02/2017)
Hospice
- Base Claim File (02/02/2017)
- Condition Code File (02/02/2017)
- Occurrence Code File (02/02/2017)
- Span Code File (02/02/2017)
- Value Code File (02/02/2017)
- Revenue Center File (02/02/2017)
Outpatient
- Base Claim File (02/02/2017)
- Condition Code File (02/02/2017)
- Occurrence Code File (02/02/2017)
- Span Code File (02/02/2017)
- Value Code File (02/02/2017)
- Revenue Center File (02/02/2017)