Medicare Health Outcomes Survey

Medicare Health Outcomes Survey Overview

Introduction to Medicare HOS

CMS is committed to monitoring the quality of care provided by Medicare Advantage Organizations (MAOs). To better evaluate this care, CMS, in collaboration with the National Committee for Quality Assurance (NCQA), launched the first Medicare managed care outcomes measure in the Healthcare Effectiveness Data and Information Set (HEDIS®) in 1998. The measure includes the most recent advances in summarizing physical and mental health outcomes results and appropriate risk adjustment techniques. This measure was initially titled Health of Seniors, and was renamed the Medicare Health Outcomes Survey during the first year of implementation. This name change was intended to reflect the inclusion of people with Medicare who are disabled and under age 65 in the sampling methodology.

The HOS measure was developed under the guidance of a Technical Expert Panel (TEP) comprised of individuals with specific expertise in the health care industry and outcomes measurement. CMS has contracted with NCQA to support the standardized administration of the HOS survey, including selecting, training, and certifying independent survey vendors that the plans contract with to administer the survey.

Medicare HOS 2.0

In the spring of 2006 CMS finalized Medicare HOS 2.0. The Medicare HOS 2.0 contains four major components:
  • the Veterans RAND 12 Item Health Survey (VR-12)
  • questions to gather information for case-mix and risk-adjustment
  • four HEDIS® Effectiveness of Care measures
  • additional health questions
Changes in HOS 2.0 from the original HOS measure (described below) include a reduction in outcome items (from 36 items to 12 items), the removal of redundant or less useful items (UI question; stroke complications), the addition of HEDIS® measures for osteoporosis testing and fall risk management, and height and weight questions for calculation of Body Mass Index. The Medicare HOS 2.0 can be downloaded from the Survey Instrument section.

Development of the Medicare HOS

In the mid-1990s, Medicare beneficiaries were joining health maintenance organizations (HMOs) and other types of managed care organizations (MCOs) in increasing numbers. It became apparent to CMS that the Agency needed performance reporting requirements for Medicare managed care. CMS worked with NCQA to incorporate the Medicare population into NCQA's HEDIS® performance measurement set. HEDIS® was rapidly becoming a standard reporting requirement of purchasers in the commercial insurance market.

The integration of the Medicare population into HEDIS® was achieved with the release of HEDIS® 3.0. CMS, NCQA, and others felt there was a need to develop additional measures for the Medicare population including an "outcomes" measure for HEDIS®. Traditionally, HEDIS® contained "process" measures that assessed interventions such as mammograms for older women and retinal eye exams for people with diabetes. While evidence in the scientific literature tied the measured processes or interventions to favorable patient outcomes, there was a desire to develop an outcomes measure that captured performance across multiple aspects of care.

CMS, NCQA, Health Assessment Lab (HAL), and performance measurement experts worked together to develop a measure that would assess the physical functioning and mental well being of Medicare beneficiaries over time. It was decided that this measure should include additional items to allow for case mix adjustment, which is essential for meaningful and valid plan-to-plan comparisons of health outcomes. The HOS measure was approved for inclusion in HEDIS® by the Committee on Performance Measurement (CPM), the NCQA panel that oversees the development and evolution of HEDIS®.

HOS results continue to be an important part of CMS' quality improvement activities, as current law authorizes QIOs to ensure that medical care paid for under the Medicare program meets professionally recognized standards of health care. Section 722 of the Medicare Prescription Drug, Improvement, and Modernization act of 2003 mandates the collection, analysis, and reporting of health outcomes information. This legislation also specifies that data collected on quality, outcomes, and beneficiary satisfaction to facilitate consumer choice and program administration must utilize the types of data collected prior to November 1, 2003. Collected since 1998, the Medicare Health Outcomes Survey is the only patient-reported outcomes measure in Medicare managed care and therefore remains a critical part of assessing health plan quality.


The Medicare Health Outcomes Survey-Modified (HOS-M)

The Medicare Health Outcomes Survey-Modified (HOS-M) is administered to vulnerable Medicare beneficiaries at greatest risk for poor health outcomes. These beneficiaries are enrolled in Program of All-Inclusive Care for the Elderly (PACE) programs. The main goal of the HOS-M is to assess the frailty of the population in these health plans in order to adjust plan payments.

The survey administration occurs annually according to the standard HOS timeline. Additional information, including the HOS-M program timeline, dissemination of results, and sample reports, may be found in the HOS-Modified Overview section.

Medicare HOS Survey Administration Timeline

A random sample of Medicare beneficiaries is drawn from each MAO and surveyed every spring (i.e., a baseline survey is administered to a new sample of members [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 most recent HOS administration (2009), Cohort 12 was surveyed and Cohort 10 was resurveyed using HOS 2.0. For data collection years 1998-2008, a member was required to be continuously enrolled in their MAO for a six month period for inclusion in the baseline sample. Effective 2009, this requirement is waived.

Medicare HOS Survey Administration Timeline
  Data Collection Reports
  Baseline Follow Up Baseline Follow Up
2010 Cohort 13 Cohort 11 Cohort 12 Cohort 10
2009 Cohort 12 Cohort 10 Cohort 11 Cohort 9
2008 Cohort 11 Cohort 9 Cohort 10 Cohort 8
2007 Cohort 10 Cohort 8 Cohort 9 Cohort 7
2006 Cohort 9 Cohort 7 Cohort 8 Cohort 6
2005 Cohort 8 Cohort 6 Cohort 7 Cohort 5
2004 Cohort 7 Cohort 5 Cohort 6 Cohort 4
2003 Cohort 6 Cohort 4 Cohort 5 Cohort 3
2002 Cohort 5 Cohort 3 Cohort 4 Cohort 2
2001 Cohort 4 Cohort 2 Cohort 3 Cohort 1
2000 Cohort 3 Cohort 1 Cohort 2  
1999 Cohort 2   Cohort 1  
1998 Cohort 1      


Medicare HOS Glossary

Medicare HOS Glossary (PDF, 91 KB). This glossary of HOS related terms, which has previously been included in the annual HOS baseline and performance measurement reports, is available for download from this section.


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