Medicare Current Beneficiary Survey
The Medicare Current Beneficiary Survey (MCBS) produces nationally representative estimates of health status, health care use and expenditures, health insurance coverage, and socioeconomic and demographic characteristics of Medicare beneficiaries. It is used to estimate expenditures and sources of payment for all services used by Medicare beneficiaries, including copayments, deductibles, and noncovered services; to ascertain all types of health insurance coverage and related coverages to sources of payment; and to trace processes over time, such as changes in health status and the effects of program changes. MCBS has two components: the Cost and Use file and the Access to Care file. Medicare claims are linked to the survey-reported events to produce the Cost and Use file, which provides complete expenditure and source of payment data on all health services, including those not covered by Medicare. The Access to Care file contains information on beneficiaries' access to health care, satisfaction with care, and usual source of care.
The overlapping panel design of the survey allows each sample person to be interviewed three times a year for 4 years, whether he or she resides in the community or a facility or moves between the 2 settings, using the version of the questionnaire appropriate to the setting. Because residents of long-term care facilities often are in poor health, information about institutionalized residents is collected from proxy respondents such as nurses and other primary caregivers affiliated with the facility. The sample is selected from the Medicare enrollment files, with oversampling among disabled persons under age 65 and among persons 80 years of age and older.
In recent rounds, data have been collected from roughly 16,000 beneficiaries. Each fall about 1/3 of the sample is retired and new sample persons are included in the survey. In the community, response rates for initial interviews range in the mid- to high-80s; once the first interview is completed, participation in subsequent rounds in 95% or more. Roughly 90% of the sample is made up of persons living in the community, with the remaining 10% in long-term care facilities. Response rates for facility interviews approach 100%.
Because only Medicare beneficiaries are included in the survey, the survey excludes the small proportion of persons aged 65 years and over who are not enrolled in Medicare. This should be noted when using MCBS data to make estimates of the entire US population aged 65 and over.
National Center for Health Statistics. Health United States 2009: With Special Feature on Medical Technology. Hyattsville, Maryland. 2010; pp 456-457.