Medicare Health Outcomes Survey

Medicare Health Outcomes Survey

Welcome to the Medicare Health Outcomes Survey (HOS) website.

The Medicare HOS is the first outcomes measure used in Medicare managed care and the largest survey effort ever undertaken by the Centers for Medicare & Medicaid Services (CMS). The goal of the Medicare HOS program is to gather valid and reliable health status data in Medicare managed care for use in quality improvement activities, plan accountability, public reporting, and improving health. All managed care plans with Medicare Advantage (MA) contracts must participate.


A random sample of Medicare beneficiaries is drawn from each participating Medicare Advantage Organization (MAO) and surveyed every spring (i.e., a survey is administered to a different baseline cohort, or group, each year). Two years later, these same respondents are surveyed again (i.e., follow up measurement). Cohort 1 was surveyed in 1998 and was resurveyed in 2000. Cohort 2 was surveyed in 1999 and was resurveyed in 2001, and so on. During the current HOS administration (2011 Round 14), Cohort 14 is surveyed and Cohort 12 is resurveyed using HOS 2.0. For data collection years 1998-2006, the MAO sample size was one thousand. Effective 2007, the MAO sample size is increased to twelve hundred.

This website is designed to provide current information on the progress of the HOS program, as well as house the full spectrum of Medicare HOS related data and reports. The following pages are included:

  • What's New provides updates on the latest HOS program developments.
  • Program Overview reviews the history of the Medicare HOS program, provides a table of the HOS survey administration timeline for the data collection, report dissemination and cohorts of data used in the CMS MA Part C Plan Ratings, and provides a glossary of terms related to the HOS.
  • Program Timeline provides a chronology of survey activities for each annual round of HOS data collection from sampling through data dissemination.
  • Survey Instrument provides downloadable versions of the questionnaire from each year of the HOS and reviews the key components of the instrument.
  • Survey Results discusses HOS performance measurement results and provides information on the HOS measures utilized in the CMS MA Part C Plan Ratings.
  • Data Dissemination provides information on the HOS reporting process and HOS contact information for Quality Improvement Organization (QIO) and MAO data users, and provides access to sample reports containing national HOS results.
  • HOS-Modified Overview reviews the Medicare HOS-Modified (HOS-M) program, which administers a modified HOS survey to members of Program of All-Inclusive Care for the Elderly (PACE) Organizations.
  • Real World Uses provides information and downloadable files on how HOS findings are used to support Medicare operations and translate research into practice, and provides self-paced training webinars about the HOS.
  • Publications provides an overview of Medicare HOS research and a comprehensive list of HOS publications, and links to HOS-related technical reports.
  • Research Data Files contains information on accessing Medicare HOS data, and includes downloadable Medicare HOS public use data files (PUFs) available for research purposes.
  • Data User's Guides contains downloadable HOS Data User's Guides which detail the QIO, MAO, and PUF data specifications, instructions, and information on how to use these data.
  • Program Partners provides information on the organizations involved in the HOS program, including links to their respective websites.
  • E-Newsletters provides information about HOS products, services and timelines; program updates; and availability of new self-paced training programs.
  • FAQs provides answers to frequently asked questions (FAQs) about the HOS program.
  • Contact Us provides pertinent contact information for the HOS program.
Health Services Advisory Group Centers for Medicare and Medicaid Services