Codes and Frequencies
For female sample adults aged 18-49 who received a flu shot and had a pregnancy in the past 12 months, PREGFLUSH indicates if they got the flu shot before, during or after this pregnancy.
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.
- 2012-2018: Female sample adults 18-49 who received a flu shot in the past 12 months and were at risk of receiving a flu shot during pregnancy.
- 2019-2022: Female sample adults age 18-49 or who don't know or refuse their age who are currently pregnant, received a flu vaccination in the past 12 months, and were at risk of receiving a flu shot during pregnancy.
- 2012-2022 : SAMPWEIGHT