SERIAL is a 6-digit numeric variable.
SERIAL is an IPUMS NHIS-constructed value that is an identifying number unique to each household in a given survey year. The combination of YEAR and SERIAL provides a unique identifier for every household in the IPUMS NHIS database.
This variable is fully comparable before 2019.
The NHIS questionnaire was substantially redesigned in 2019 to introduce a different data collection structure and new content. For more information on changes in terminology, universes, and data collection methods beginning in 2019, please see the user note.
- 1963-2018: All households.
- 2019-2020: Sample adults age 18+ and sample children age 0-17.
- No weights are available for this variable. Please refer to SERIAL for more information.