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Medicare HOS Data Files

Several types of Medicare HOS data files are available for research purposes. Medicare HOS data files are available as public use files (PUFs), limited data sets (LDSs), and research identifiable files (RIFs).

HOS PUFs contain the majority of the survey items collected on the HOS instrument (excluding beneficiary identifying information) as well as selected additional administrative variables. HOS PUFs are constructed to prevent the identification of any single beneficiary or plan and only respondents to the survey are included in the files. HOS PUFs are available at no cost and can be downloaded directly from this page (see below for additional information).

HOS LDSs and RIFs are comprised of the entire national sample for a given cohort (including both respondents and non-respondents), and contain all of the HOS survey items. HOS LDSs and RIFs also contain protected beneficiary-level health information such as date of birth; however, specific direct person identifiers (i.e. name and health insurance claim number) are not included in LDSs. The HOS LDSs and RIFs include plan identifiers as well as several additional variables describing plan characteristics. A signed Data Use Agreement with CMS is required to obtain either LDS or RIF data files. The Research Data Assistance Center (ResDAC) at the University of Minnesota is a CMS contractor that provides assistance to academic, government and non-profit researchers interested in using Medicare and/or Medicaid data. ResDAC is available to assist in the completion and/or review of data requisition forms for Medicare HOS research data files prior to their submission to CMS. For additional information and assistance with obtaining Medicare HOS LDS and RIF files, please visit the ResDac Medicare HOS Web page. ResDAC may also be contacted by calling 1-888-9RESDAC (1-888-973-7322) or by e-mailing resdac@umn.edu.

Medicare HOS Public Use Data Files

In order to facilitate the dissemination of data collected by the Medicare HOS project for additional research, PUFs have been created for each cohort of data. The HOS PUFs contain the majority of the survey items collected on the HOS instrument (excluding beneficiary identifying information) as well as selected additional administrative variables. The files have been constructed in accordance with current CMS and Department of Health and Human Services (HHS) policies and other applicable statutes and laws. All identifying information has been excluded from the files, and demographic categories have been aggregated such that identification of any given individual is not possible.

Three distinct categories of PUFs have been generated:

1. Baseline PUFs contain the data collected during a given baseline survey administration.
2. Follow Up PUFs contain the data collected during the follow up survey administration which occurs two years after the baseline survey administration.
3. Analytic PUFs contain the merged baseline and follow up files as well as supplemental variables.

The PUFs are formatted as fixed-width ASCII (flat) files. The PUF ASCII files are bundled together (as a ZIP file) with additional documentation that details the construction and content of each PUF. The detailed documentation is provided in the form of a Data User's Guide. Additional information on HOS PUF Data User's Guides is presented in the section entitled Data User's Guides.

Medicare HOS Downloadable PUFs

Once Medicare HOS PUFs are completed, they are available for download from this page. If you have any questions regarding the PUFs, please feel free to contact the Medicare HOS Information and Technical Support Line.

COHORT I

• Medicare HOS Cohort I Baseline PUF Data  (ZIP, 5.8 MB) - fielded Spring 1998
• Medicare HOS Cohort I Follow Up PUF Data  (ZIP, 2.7 MB) - fielded Spring 2000
• Medicare HOS Cohort I Analytic PUF Data  (ZIP, 6.8 MB) - 1998 - 2000

COHORT II

• Medicare HOS Cohort II Baseline PUF Data  (ZIP, 6.8 MB) - fielded Spring 1999
• Medicare HOS Cohort II Follow Up PUF Data  (ZIP, 2.6 MB) - fielded Spring 2001
• Medicare HOS Cohort II Analytic PUF Data  (ZIP, 7.0 MB) - 1999 - 2001

COHORT III

• Medicare HOS Cohort III Baseline PUF Data  (ZIP, 7.0 MB) - fielded Spring 2000
• Medicare HOS Cohort III Follow Up PUF Data  (ZIP, 2.5 MB) - fielded Spring 2002
• Medicare HOS Cohort III Analytic PUF Data  (ZIP, 6.9 MB) - 2000 - 2002

COHORT IV

• Medicare HOS Cohort IV Baseline PUF Data  (ZIP, 4.3 MB) - fielded Spring 2001

COHORT V

• Medicare HOS Cohort V Baseline PUF Data  (ZIP, 3.9 MB) - fielded Spring 2002

Continue on to the Data User's Guides section.

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