SEER-Medicare: SEER Program & Data

Overview of SEER

The SEER Program is an epidemiologic surveillance system consisting of population-based tumor registries designed to track cancer incidence and survival in the United States. Collection of the SEER data began on January 1, 1973. The registries routinely collect information on newly diagnosed cancer patients residing in geographically defined areas.

The SEER data contain information about an incident cancer diagnosis and cancer-directed surgery and radiation therapy provided for first course of treatment. The registries collect information about all primary cancers that a person may develop. The SEER data do not capture information about surgery and radiation provided past four months of diagnosis, nor is there information about recurrence or metastasis that is detected subsequent to the initial diagnosis. For more information about the SEER program and data, please see the SEER Home PageExternal Web Site Policy.


The SEER data released as part of SEER-Medicare are in a customized file known as the Patient Entitlement and Diagnosis Summary File (PEDSF). PEDSF contains one record per person for individuals in the SEER database who have been matched with Medicare enrollment records. Basic SEER diagnostic information is available for up to 10 diagnosed cancer cases for each person. Refer to the 5-digit Site Recode DictionaryExternal Web Site Policy for the list of cancers available. PEDSF includes information on each person's month and year of birth, date of death (if any), sex, race, and state of residence. It also contains variables from other sources that have been added to assist investigators in their analyses. These include Medicare eligibility, reason for Medicare entitlement, and health maintenance organization (HMO) enrollment by month for the period 1991 – 2015. In addition, there are separate files that contain geographically-based (ZIP code and census tract level) socioeconomic information from the 1990 and 2000 Censuses and the 2008 – 2012 American Community Survey.

The 5% All Cancer Diagnosis File (PDF, 311 KB) may also be useful to investigators examining cancer etiology. SEER-Medicare data files can be extremely large and challenging to analyze without large computing capabilities (e.g., servers with large processing memory and storage space). Using a subset of cancers diagnosed in the SEER-Medicare 5% sample allows for more manageable analytic file sizes, particularly for questions evaluating cancer in general as an outcome.

PEDSF File Documentation is available. All SEER variables copied directly from the SEER file are described in the SEER Research Data Record Description.