SEER-Medicare: Variables Restricted from Routine Release & Encrypted Variables
For reasons of confidentiality, selected variables are not routinely released on the
SEER-Medicare files. These variables include the patient's Census tract and ZIP code, as
well as the ZIP code for physicians. Selected Census data from 1990 and 2000
for each ZIP code and Census tract have been included on the PEDSF file (see PEDSF file
documentation). These variables have been slightly altered to prevent matching back to the
Census data and identifying the actual Census tract or ZIP Code.
To protect the identity of individual hospitals and physicians, the hospital numbers
and Unique Physicians Identifier Numbers (UPINs) on the Medicare claims are encrypted
prior to release of the data. However, investigators who want to include provider
characteristics as part of their analysis may do so, as described below.
For researchers who wish to obtain hospital characteristics, NCI has created a file
that includes information about hospitals that are part of the SEER-Medicare data (see the
hospital file description in PDF
format). The hospital identifiers on this file are encrypted and can be
readily linked to the encrypted hospital numbers on the Medicare claims. This file will be
made available without charge to investigators. Investigators must include a description
of the use of the hospital file in their proposal requesting SEER-Medicare data.
Investigators who wish to obtain information about physician characteristics, such as
demographics, medical specialty, and board certification, can arrange for the UPINs
identified from the Medicare carrier data to be linked to data collected by the American
Medical Association (AMA). This linkage is accomplished by sending to NCI's programming
contractor, IMS, the UPINs the researchers wishes to be linked. Please e-mail the UPINs
list to Bob Banks at
IMS will unencrypt the
UPINs and send them to the AMA's programming contractor, Medical Marketing Service. Upon
completion of the linkage to the AMA data, IMS will return to the investigator a file with
encrypted UPINs and the selected AMA variables. Investigators must negotiate directly with
Medical Marketing Services, Inc. about the variables needed and the cost of any processing.
Please direct any inquiries to:
Medical Marketing Services, Inc.
185 Hansen Court, Suite 110
Wood Dale, IL 60191
If investigators determine that restricted or unencrypted variables are an essential
part of their analysis, they must submit their completed application form to the SEER-Medicare contact with a detailed justification for access
to the restricted/unencrypted variable(s). A completed and signed request form and a list of people that will have
access to these data must be included with the request. Once NCI supports the request for
these variables, investigators must obtain permission from each of the registries prior to
release of restricted/unencrypted variables for that registry. If investigators request
access to the unencrypted unique physician identification number (UPIN), they will also
have to secure the approval of CMS. The SEER-Medicare contact will provide investigators
with contact information for the SEER registries and CMS.
Note: In order to combine multiple requests when purchasing data, the
requests must have the same permissions for access to any restricted variable.