Health Outcomes Survey (HOS)

Welcome to ResDAC's HOS Data Page. This page provides information about HOS data files and resources available for research.

About HOS | Available HOS Data | Requesting HOS Data
HOS Data Documentation

About the Medicare Health Outcomes Survey (HOS)

The Medicare Health Outcomes Survey (HOS) was launched in 1998 as a part of the Health Plan Employer Data and Information Set (HEDIS®). The measure was initially titled Health of Seniors, and was renamed during the first year of implementation. This name change was intended to reflect the inclusion of Medicare beneficiaries who are disabled and under age 65 in the sampling methodology.[1]

As an evaluation tool, the HOS is the first measure of its kind to assess the ability of the Medicare Advantage Organization (MAO) (formerly Medicare + Choice Organization) option to maintain or improve the physical and mental health functioning of its Medicare beneficiaries over a two-year measurement period. The Centers for Medicare & Medicaid Services (CMS), the National Committee for Quality Assurance (NCQA), and other HOS Partners have worked together to develop and administer the HOS and disseminate the results to Quality Improvement Organizations (QIOs), participating MAOs, and other researchers. The goal of the Medicare HOS program is to gather valid, reliable, and clinically meaningful health status data in Medicare managed care for use in quality improvement activities, plan accountability, public reporting, and improving health. The HOS results are an important part of CMS's quality improvement activities, as the HOS results are one component of CMS's performance assessment program.

The Medicare HOS instrument consists of physical and mental health status questions and additional items, including those used for case mix and risk adjustment purposes. The HOS web site provides detailed information on the development of the HOS, survey participants, published reports, and survey instrument.

Available HOS Data

For research purposes, HOS data are available from CMS as a Public Use File (PUF), Limited Data Set (LDS) or Research Identifiable File (RIF).

HOS PUFs

The HOS PUFs can be downloaded from the CMS web site for research purposes. The PUFs are formatted as zipped, fixed width ASCII (flat) files. HOS PUFs contain the majority of the items collected on the HOS instrument (excluding beneficiary identifying information and aggregating demographic categories to prevent the identification of individual respondents). Each blinded beneficiary record is assigned a random ID, and any beneficiary resurveyed in a subsequent cohort is assigned the same blinded ID.

The HOS PUFs have been modified from the research identifiable data set in order to preserve confidentiality at the beneficiary and plan levels. Sensitive beneficiary identifying variables such as, but not limited to, social security number, health insurance claim (HIC) number, and beneficiary name have been removed and replaced with a unique 9-digit randomly assigned number.
HOS LDS

The HOS LDS contains protected beneficiary level health information but excludes direct person identifiers. The files are prepared in accordance with the standard limited data set specifications outlined in the HIPAA Privacy Regulation Text and published in the Code of Federal Regulations (CFR) 164.514(e)(2). Identifier variables that were excluded from the LDS include the Health Insurance Claim (HIC) number, address, and the name of the person to whom the survey was addressed and the name of the person who completed the survey. The LDS is prepared by CMS as a SAS-formatted file on CD-ROM. A comprehensive HOS LDS data dictionary, containing available LDS research variables, may be downloaded from the HOS web site.
HOS RIFs

The HOS RIF may include direct person level identifiers (e.g., health insurance claim (HIC) number, name, and address) NOT available in the HOS LDS. The HIC number, for example, is needed to link the HOS data to CMS's Medicare enrollment and claims data. The HOS RIF is prepared by CMS as a SAS-formatted file on CD-ROM. A comprehensive HOS RIF data user's guide, containing available RIF research variables, is available and distributed with HOS RIFs.

Like the HOS LDS, the HOS RIF contains all items included in the HOS Instrument.

Requesting HOS Data

Please go to the CMS web site for information on how to obtain HOS PUFs.
The HOS LDS request process is similar to requesting other limited data sets from CMS. A signed LDS Data Use Agreement (DUA), a LDS request form, and a 2-3 page research application must be submitted to, and approved by CMS to obtain the HOS LDS. Please see the CMS policies and procedures for LDS files for information on how to complete an LDS application. If you need further assistance preparing the request materials or have questions regarding the required documentation, please contact ResDAC.
The HOS RIF request process is similar to requesting other research identifiable files from CMS.

HOS Data Documentation

(Data Documentation is sometimes referred to as data dictionaries, file layouts, and data layouts)

The HOS Data User's Guides provide data file variable specifications and instructions for using the PUFs. NOTE: Comprehensive HOS LDS and RIF Data User's Guides are being prepared and scheduled for release in 2004. These User's Guides will contain detailed information for all variables available with the HOS LDS and/or the HOS RIF.

A SAS PROC CONTENTS page and detailed descriptive file characteristics documentation are included with the shipment of HOS LDS and RIF data under a signed DUA.

The Health Services Advisory Group offers technical support to researchers analyzing HOS PUF, LDS, and RIF data files.

Footnotes

[1] Centers for Medicare & Medicaid Services. Health Outcomes Survey Sub-Directory: http://www.cms.hhs.gov/hos/.

Last Modified September 29, 2008