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
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.