Merged Data Requests

Researchers can request that their patients or research participants be linked, or merged, with USRDS ESRD data. The approval process for a merged data request is similar to the process for requesting Standard Analysis Files (SAFs). Researchers should submit a Research Proposal, documentation of approval from an Institutional Review Board (IRB), and a completed Merged Dataset Agreement for Release of Data to the USRDS Coordinating Center (see below). The USRDS Coordinating Center will send this material to the USRDS COR (NIDDK) for review and possible approval. Once NIDDK approves the proposal and release of data, the USRDS CC will request a finder file with identifying information (name, SSN, DOB, sex) in order to complete the merge (see below for details on formatting).

Because merged data requests require programmer and analyst effort, the USRDS performs a limited number of merges each year, and researchers can typically request only one merge per year.

The USRDS cannot release data to researchers located outside of the US. For more information, see the ResDAC website.


There is no cost for a linkage or for the standard analysis files.

Merged Data Use Request

Once a merged data request is approved, requestors will need to submit a patient finder file to be matched with the USRDS database. Our preferred identifier variables and data formats are:
  • An internal unique identifier (assigned by the requestor)
  • SSN – text, nine digits, including leading zeros OR HIC – text
  • Date of birth – numeric, mmddyyyy if possible
  • First name - text
  • Last name - text
  • Sex – character, M or F
  • Date of death, if available

The preferred file format is an encrypted SAS dataset (SAS. 9.4), but a delimited flat file (.txt or .csv) or an MS Excel file (.xlsx) is also acceptable. After merging your file with the USRDS database, the Coordinating Center will return a crosswalk file containing the unique identifier you provided and the USRDS ID for all identified individuals. USRDS does not provide nor return unique patient identifiers. Secure options for finder file submission will be discussed once your request has been approved.

More information is provided in the Researcher's Guide to the USRDS Database.

USRDS Data Publication

Planned publications based on USRDS data must be submitted for privacy assurance review to the USRDS Coordinating Center at, in accordance with the USRDS Manuscript Approval Request Checklist (PDF, 168.38 KB)   . Please use the subject line: “USRDS manuscript.” Privacy assurance requests should also include the approved Data Use Agreement (DUA) number.


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Last Reviewed May 2024