Codes and Frequencies
For all persons, INTERVWMO indicates the month that the National Health Interview Survey (NHIS) was conducted.
Users should note that this variable is not available for 2019. Aside from that, this variable is fully comparable across all years. 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.
- 1969-2018: All persons.
- 2020-2022: All persons.
- 1969-2018, 2020-2022