Codes and Frequencies
For sample adults age 18+ who, without using special equipment, had any difficulty with one or more functional activities (FLANY), FLNERVES reports whether the respondent specified a nervous system condition as a cause of any functional activity limitation, instead of identifying one or more of the selections on the interviewer-provided flashcard listing possible causes of functional activity limitations.
FLNERVES is one of a set of variables in the Health Status and Limitation of Activities section of the NHIS Sample Adult Core. The question, "What condition or health problem causes you to have difficulty with these activities?," (with a nervous system condition as a National Center for Health Statistics (NCHS) ad hoc recoding of a verbatim respondent specification that could not be back-coded to one of the possible conditions on the interviewer-provided flashcard) is asked of sample adults, age 18+, only if at least one question relating to activities of daily living is answered with "only a little difficult," "somewhat difficult," "very difficult," or "can't do at all."
These questions on activities of daily living are:
Possible causes of a functional activity limitation, listed on the flashcard provided to respondents, were:
- Vision/problem seeing (FLVISION)
- Hearing problem (FLHEAR)
- Arthritis/rheumatism (FLARTH)
- Back or neck problem (FLBACK)
- Fractures, bone/joint injury (FLFRACT)
- Other injury (FLOTHINJ)
- Heart problem (FLHEART)
- Stroke problem (FLSTROKE)
- Hypertension/high blood pressure (FLHYPER)
- Diabetes (FLDIABET)
- Lung/Breathing problem (FLLUNG)
- Cancer (FLCANCER)
- Birth defect (FLBIRTH)
- Mental retardation (FLRET)
- Other developmental problem (e.g., cerebral palsy) (FLOTHDEV)
- Senility (FLSENILE)
- Depression/anxiety/emotional problem (FLDEPRES)
- Weight problem (FLWEIGHT)
Other possible causes of functional activity limitations not listed on the flashcard provided to respondents, but used by the NCHS to recode, ad hoc, an "other" verbatim respondent answer to the question, "What condition or health problem causes you to have difficulty with these activities?," include:
- Alcohol or drug problem (FLALC)
- Benign tumor (FLBENIGN)
- Blood problem (FLBLOOD)
- Circulatory problem (FLCIRC)
- Digestive problem (FLDIGEST)
- Endocrine problem (FLENDO)
- Other mental problem (FLMENTAL)
- Fatigue (FLFATIG)
- Genitourinary problem (FLGENITO)
- Missing limb or finger (FLLIMB)
- Old age (FLOLDAGE)
- Pregnancy (FLPREG)
- Skin problem (FLSKIN)
- Surgical after-effects (FLSURGRY)
- First unclassified problem (FLNEC1)
- Second unclassified problem (FLNEC2)
The 1997 forward NHIS Survey Descriptions caution that the ad hoc classified condition categories were not included on flashcards given to respondents during the course of the interview. Thus, the NCHS recommends that "these variables should be analyzed with care."
The following definitions provide information about various concepts used in the sequence of questions identified above:
For 2002 forward, the variable is completely comparable.
For 1997-2001, a small number of cases were coded as "no condition at all" (IPUMS NHIS code 6) for the cause of functional activity limitation.
If researchers are interested in only sample adults age 18+ with at least one condition causing a functional activity limitation, then the response of "no condition at all" can be recoded as "not in universe" (IHIS code 0). Using this recode, the variable is completely comparable for 1997 forward.
Additionally, for 1997-1999, several of the variables that asked about degrees of functional activity limitation were recoded by the NCHS in the course of their data editing.
For three activities (shopping FLGOOUT, participating in social activities FLSOCIAL, and relaxing at home FLRELAX), respondents could indicate that they "do not do this activity." For all other activities, respondents were not permitted to answer that they "do not do this activity," but could be assigned to the category by the NCHS in the course of data editing based on information obtained by the interviewer.
- 1997-2013; 2014 2015 2016 2017 2018: Sample adults age 18+ who, without using special equipment, have at least a little difficulty with one or more functional activity.
- 1997-2018 : SAMPWEIGHT