Codes and Frequencies
For Sample Adults age 18+ who, without using special equipment, had any difficulty with one or more functional activities (FLANY), and for whom a vision problem or problem seeing was reported as a condition causing a functional activity limitation (FLVISION), FLVISIONTP reports the time unit in which the duration of the vision problem or problem seeing was measured by the respondent.
Data on the duration of the limiting vision problem or problem seeing were collected via the question, "How long have you had [a vision problem or problem seeing]?" Respondents could answer this open-ended question using the time unit of their choice (i.e., days, weeks, months, years, or since birth). The original responses to the question are reported in two complementary variables, FLVISIONTP (which, as noted above, specifies the time unit) and FLVISIONNO (which reports the number of such units). For the NHIS public use files, the National Center for Health Statistics (NCHS) recoded the results from these two variables to create two other variables using standard time units: years (FLVISIONY) and groups of months (FLVISIONMO).
- 1997-2013; 2014 2015 2016 2017 2018: Sample adults age 18+ who have difficulty with activities due to vision problem.
- 1997-2018 : SAMPWEIGHT