SEER-Medicare: Provider Files

As part of SEER-Medicare analyses, researchers may want to include information about physicians or hospitals providing care to patients. Information about physicians can be obtained from data collected by the American Medical Association. See Variables Restricted from Routine Release & Encrypted Variables for more information.

For hospital characteristics, NCI has created a Hospital File that includes information about hospitals that are part of the SEER-Medicare data. Information about these hospitals has been obtained from several sources. Each year, the Center for Medicare and Medicaid Services (CMS) requires hospitals that bill to the Medicare and Medicaid program to submit an annual report, the Healthcare Cost Report (HCRIS). In addition, as part of its certification process, CMS periodically requires institutions to complete the Provider of Service (POS) survey. NCI has extracted selected variables from the HCRIS and POS files from 1996, 1998, and 2000-2009 to be included in the Hospital File. It should be noted that there are differences between the HCRIS and POS files as to exact time periods and how selected variables are defined. NCI has not attempted to resolve any inconsistencies between files, but is making researchers aware of these differences. Close examination of the data may be needed. In addition to information from CMS, the Hospital File includes information about whether the institution was an NCI-designated cancer center as of 2002, 2005, and 2010. There are also variables denoting if the hospital participated in any NCI-sponsored cooperative group trials.

Hospital Mergers & Acquisitions

When a hospital undergoes a merger, acquisition or closure, the associated hospital provider number (Provnum) often changes, creating challenges for tracking providers over time. The Hospital file itself contains no distinguishing identifier for researchers to link information on current and past hospital provider numbers for a facility. However, researchers interested in tracking hospital providers over time are encouraged to use the Mergers and Acquisitions file maintained by NCI.

The Mergers and Acquisitions file was created from the Provider of Service (POS) files released by the Centers for Medicare and Medicaid Services (CMS), which collect information on previous or associated provider numbers for a hospital. The Mergers and Acquisition file contains one observation per provider number (current or previous). Along with each provider number, the file includes a linking variable (Group_id) that assigns a unique identifier to all associated provider numbers identified across all years of the hospital file, if any. If a hospital has no associated provider numbers, the Group_id variable will have a missing value for that provider. All provider numbers are encrypted in the same way as other files in the SEER-Medicare data to allow for linkage.

The Hospital and Mergers and Acquisitions files will be made available without charge to investigators. Investigators must include a description of the use of these files in their proposal requesting SEER-Medicare data.

Documentation for the Hospital and Mergers and Acquisitions files is available in PDF format.