The Medicare Current Beneficiary Survey

Since its inception in 1991, the Medicare Current Beneficiary Survey (MCBS) has served as an invaluable source of information for administering, monitoring, and evaluating the Medicare program. A leading source of information on Medicare and its impact on beneficiaries, the MCBS provides important data on beneficiaries that are not available in CMS administrative data and plays an essential role in monitoring and evaluating beneficiaries’ health status and health care policy. The MCBS collects comprehensive data on beneficiaries’ health insurance coverage, health care utilization and costs, access to care, and satisfaction with care, as well as special interest topics including drug coverage, knowledge about the Medicare program and housing characteristics. Data from the MCBS are used to inform many government programs and analyses, including fiscal projections produced by the Congressional Budget Office and the Medicare Payment Advisory Commission, and are published in a wide array of peer-reviewed journals.

The MCBS is a continuous, in-person, multi-purpose survey of a representative national sample of the Medicare population, including the population of beneficiaries aged 65 and over and beneficiaries aged 64 and below with eligible disabilities, residing in the United States. It is sponsored by the Office of Enterprise Data and Analytics (OEDA) of the Centers for Medicare & Medicaid Services (CMS). In its rotating panel design, each sampled beneficiary is scientifically selected as part of a panel and is interviewed up to three times per year over a four year period. The MCBS has been carried out continuously for more than 25 years, and more than one million interviews have been conducted since its inception. NORC conducts the full range of MCBS survey activities including sampling, data collection, data processing, editing, imputation, and delivery of files to CMS for final processing and dissemination.

Designed to aid CMS in administering the Medicare program, the MCBS is distinguished by several unique features, including:

  • Linked survey-reported and administrative claims data: The MCBS collects survey-reported health care utilization and cost data and links it to Medicare Fee-for-Service claims data, providing researchers and policy analysts with more accurate and complete estimates of beneficiaries’ total health care utilization and costs than would be captured through either source alone.
  • Complete source of payment information: The MCBS collects survey-reported data on all sources of payment for health care costs, including sources of payment for costs not covered by Medicare (e.g., co-payments and deductibles) as well as sources of payments for services not covered by Medicare (e.g., home health care). MCBS data also reveal how much retiree benefits, Medigap, VA benefits and other sources of coverage cover health care costs.
  • Medicare Advantage (MA) beneficiary data: The MCBS collects comprehensive survey-reported healthcare utilization and cost data for beneficiaries covered by Medicare Advantage, allowing researchers to analyze MA beneficiary cost and utilization data in the absence of Medicare Advantage claims data.
  • Inclusion of facility-dwelling beneficiaries: The MCBS follows beneficiaries into and out of long-term care facilities to maintain a comprehensive profile of their health care utilization and expenditures. Facility interviews are conducted with facility staff instead of the actual beneficiary. The Facility Instrument is modeled after the Minimum Data Set (MDS) assessment, and facility interviewers are trained to abstract interview responses directly from medical records.

The MCBS data are available to users via two annual Limited Dataset (LDS) files. The MCBS LDS files include the Survey File (formerly referred to as the Access to Care file) and the Cost Supplement File (a modified version of what was formerly referred to as the Cost and Use file). The Survey File contains information on beneficiaries’ socio-demographics, health insurance coverage, self-reported health status and conditions, and responses regarding access to care and satisfaction with care. Survey data are supplemented by Medicare administrative data and Medicare Fee-for-Service (FFS) claims to facilitate analysis. The Cost Supplement File contains survey-reported data on beneficiaries’ healthcare utilization, expenditures, and sources of payment, including out-of-pocket costs and payments. The Cost Supplement File can be linked to the Survey File to conduct analyses on healthcare cost and utilization. By linking survey-reported data in the Cost Supplement File to Medicare FFS claims data in the Survey File, data users can obtain a comprehensive picture of health services received, amounts paid, and sources of payment, including those not covered by Medicare.

In recent years, CMS and NORC have undertaken a number of improvements to greatly increase the accessibility and utility of the survey. Starting with the 2013 data year, CMS began releasing an annual Public Use File to allow researchers to conduct analyses on health disparities, access to and satisfaction with healthcare, and medical conditions for community-dwelling Medicare beneficiaries. Additionally, beginning with the 2015 data year, NORC supported CMS in releasing a new, comprehensive and integrated suite of public resources for data users to understand the importance and complexity of the MCBS. These resources include three annual MCBS Data User’s Guides that accompany the Limited Data Set (LDS) releases, an annual MCBS Methodology Report, an annual Chartbook, and a set of tutorials for new data users. In the future, NORC will be adding a new resource to this portfolio of documentation: an annual “Early Look” that summarizes key estimates. This resource will provide preliminary estimates that will be released prior to the MCBS data release and the MCBS Chartbook publication, facilitating the timely dissemination of MCBS data to the public.