After suspension of NHANES field operations in March 2020 due to the COVID-19 pandemic, data collection began for a new 2-year cycle in August 2021. The August 2021-August 2023 nationally representative data files are based on an updated sample design and modified questionnaires, and examination procedures. Please see the links below for a brief overview and analytic guidance and the Plan and Operations Report for additional information on the collection and use of the data.
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