Codes and Frequencies
For sample children and sample adults (or, prior to 2019, all persons) born outside the United States, YRSINUSG indicates how long they have been living in the United States. In most cases, this information was collected via the question, "In what year did you come to the United States to stay?" If the response to this question was "refused" or "don't know," the interviewer tried to collect the information via an alternatively phrased question: "About how long have you been in the United States?"
The data included in the public use files for YRSINUSG are recodes of the responses to these questions, with each answer in the form of a calendar year converted to a number of years present. The calendar year format of the initial question would have increased the precision of responses by discouraging rounding; the recoded format (number of years present) is easier for researchers to analyze.
According to the 2020 Survey Description, for some variables, including YRSINUSG, 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.
Apart from universe changes and changes in the meaning of "born in the U.S.," this variable is largely comparable over time. Beginning in 2019, this information was not collected for persons born in a U.S. territory; prior to 2019, persons born in a U.S. territory were asked how long they had been in the U.S.
Another notable change affects only a few cases in which respondents did not answer the initial question ("In what year did you come to the United States?") and did answer the follow-up probe ("About how long have you been in the United States?")
The survey form for 1998-1999 states that answers of less than one year present should be coded "1" (i.e., grouped with answers meaning one year to less than two years); the form for 2000 forward states, "If less than one year given as a response, code the answer as '0'." The 1997 survey form did not discuss how to code answers referring to a period of less than 1 year for this follow-up question. That year's form only allowed interviewers to record a number between 1 and 95, so presumably those who had been in the country for less than one year were given a code of "1" by the interviewer, as in 1998-1999.
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.
- 1989-1992: Persons age 18+ not born in one of the 50 states or D.C.
- 1993-1996: Persons not born in one of the 50 states or D.C.
- 1997: Sample adults age 18+ not born in the United States.
- 1998-2018: All persons not born in one of the 50 U.S. States or D.C.
- 2019-2021: Sample children age 0-17 and sample adults age 18+ who were not born in one of the 50 U.S. states, D.C., or a US territory (USBORN).