Sample Design
The National Health and Aging Trends Study (NHATS) aims to follow a sample of over 8,000 Medicare beneficiaries ages 65 and older through annual in-person data collection. The study sample is designed to represent the Medicare population of persons ages 65 and older. The NHATS sample design is age-stratified so that persons are selected from 5 year age groups between the ages of 65 and 90, and from among persons age 90 and older. This design oversamples persons at older age groups. Persons whose race is listed as Black on the CMS enrollment file are oversampled as well. Replenishment of the sample to maintain its ability to represent the older Medicare population is planned at 5 year intervals.
Details of the NHATS sample design can be found in a forthcoming document.
