Codes and Frequencies
For all sample children and sample adults who did not have a don't know, not ascertained, or refused response to whether they were born in the United States or a United States territory (USBORN), CITIZEN indicates whether the individual was a U.S. citizen. Prior to 2019, this variable was available for all persons.
According to the 2020 Survey Description, for some variables, including CITIZEN, the 2020 responses of sample adults that were part of the 2020 longitudinal sample were overwritten with their 2019 responses "to mitigate disclosure risks associated with differences in response from repeated measures among the same Sample Adults" (33). The sample adults' actual 2020 responses can be accessed through a Research Data Center (RDC). For more information on the 2020 longitudinal sample, please see SALNGPRTFLG.
Changes in data collection and universe may affect the comparability of this variable over time. The way this information was collected has changed slightly over time and the universe changed starting in 2019, primarily as a result of the 2019 redesign of the NHIS data collection process and questionnaire, where a single randomly sampled child and adult per household were surveyed, rather than all household members.
From 1998-2018, this variable is a recode of more detailed information collected in response to the question, "Are you a citizen of the United States?" In the recoded CITIZEN variable, the affirmative value (IPUMS NHIS code 2) includes the following categories: Yes, born in one of 50 U.S. states or the District of Columbia; Yes, born in Puerto Rico, Guam, American Virgin Islands, or other U.S. territory; Yes, born abroad to American parent(s); and Yes, U.S. citizen by naturalization.
Beginning in 2019, sample adults and children who did not give an answer of "don't know," their information was not ascertained, or they refused to answer whether they were born in the United States or a U.S. territory were asked two follow up questions. First, whether they were a citizen of the U.S. and, if they reported they were not born in the U.S. but were U.S. citizens, second, whether they were "born abroad to an American parent, born abroad and adopted by an American parent, or…[became] a U.S. citizen by naturalization." The responses to the detailed citizenship and naturalization questions were recoded into the CITIZEN variable. The meaning of an affirmative value on CITIZEN now also includes "born abroad and adopted by an American parent."
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.
- 1998-2018: All persons.
- 2019-2020: Sample children aged 0-17 and sample adults aged 18+ who did not give a refused, not ascertained, or don't know response when asked whether they were born in the U.S. (USBORN).