Enhancing Weighting in the National Health and Nutrition Examination Survey (NHANES) with External Data

Oregon Convention Center 

For many surveys, limited information is available for nonrespondents, which can lead to biased estimates if the nonrespondents have unknown characteristics different from the respondents. Area-level estimates from reliable external sources, such as the American Community Survey, can be utilized in the weighting adjustment process to try to reduce this bias. The National Health and Nutrition Examination Survey (NHANES), like many other government surveys, has had a decline in response rates in recent years. As a result, the weighting process has been reviewed for potential changes that account for nonresponse. To address this need, we expanded the use of auxiliary data (e.g., area-level estimates from the American Community Survey (ACS) and other external sources) and introduced paradata in the form of interviewer observations of sampled households at the first contact attempt. We will show how these are used in both weighting adjustments and the general nonresponse bias assessments for the NHANES August 2021-August 2023 data.