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 blood problem was reported as a condition causing a functional activity limitation (FLBLOOD), FLBLOODTP reports the time unit in which the duration of the blood problem was measured by the respondent.
Data on the duration of the limiting blood problem were collected via the question, "How long have you had [a blood problem]?" 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, FLBLOODTP (which, as noted above, specifies the time unit) and FLBLOODNO (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 (FLBLOODY) and groups of months (FLBLOODMO).
The 1997 forward NHIS Survey Descriptions caution that because the ad hoc classified condition categories (such as a "blood problem" (FLBLOOD)) were not included on flashcards given to respondents during the course of the interview, it is possible that weighted frequencies for these conditions may be underestimated. Thus, the NCHS recommends that "these variables should be analyzed with care."
- 1997-2013; 2014 2015 2016 2017 2018: Sample adults age 18+ who have difficulty with activities due to blood problem.
- 1997-2018 : SAMPWEIGHT