Codes and Frequencies
ASTHMAEV identifies sample adults and sample children whom a doctor or other health professional had ever diagnosed as having asthma. In 1988, ASTHMAEV was asked of sample persons under 18 and in 1993 was asked of half of sample persons age 18 and older in quarters 3 and 4.
The Field Representative's Manuals for 1997-2000 directed interviewers to "accept asthma of any kind, such as smoker's asthma, bronchial asthma, allergic asthma, and the like," but to "not accept self-diagnosed lung problems or conditions reported by a person who is not a doctor and not working with or for a doctor."
The Manual provided definitions of asthma, but these definitions were not routinely shared with respondents. In 1998-2000, asthma was defined as "a condition marked by recurrent attacks which include breathing difficulty and wheezing." Beginning in 2001, asthma was defined as "a chronic respiratory disorder characterized by labored breathing and wheezing resulting from obstructed and constricted air passages."
Some asthma-related variables, such as ASTHMAEV, were included in the National Health Interview Survey (NHIS) every year, beginning in 1997. From 1997 forward, the NHIS included questions about whether, in the past 12 months, individuals had an asthma attack (ASTHATAKYR) and had visited an emergency room for asthma (ASTHERYR). Beginning in 2001, individuals ever diagnosed with asthma were consistently asked whether they still had asthma (ASTHMASTIL).
Most of the questions related to asthma were, however, only included in the survey periodically. The 1999 and 2003 surveys were particularly notable for the large number of asthma-related variables they included. According to the 2003 Manual, the new asthma questions for that year were "part of the Healthy People 2010 Initiative."
One group of the "periodic" asthma questions addressed the effects of the illness, in terms of the use of health care or disability days. Variables in this group included:
- Had hospital stay for asthma, past 12 months (ASTHOSPYR, in 1999, 2003, 2008, 2013)
- Number hospital stays for asthma, past 12 months (ASTHOSPYRNO, in 1999)
- Days missed due to asthma, past 12 months (ASTHDAYR, in 2002-2003, 2008, 2013)
A second group of periodically-available asthma questions dealt with the use of asthma medications. These included:
- Used over the counter meds for asthma, past 12 months (ASTHOTCYR, in 1999)
- Used prescription inhaler, past 3 months (ASTHPIN3MO, in 1999)
- Number canisters prescription inhalers used, past 3 months (ASTHCANSNO, in1999)
- Ever used prescription inhaler (ASTHPINEV, in 2003, 2008)
- Used prescription inhaler for quick relief, past 3 months (ASTHPINQUICK, in 2003, 2008, 2013)
- Used more than 3 cans prescription inhaler, past 3 months (ASTHCANGT3, in 2003, 2008, 2013)
- Ever taken preventive asthma meds (ASTHPREV, in 2002-2003, 2008)
- Now taking preventive asthma meds (ASTHPRENOW, in 2003, 2008, 2013)
The third group of periodically-available asthma-related questions covered "patient education," broadly defined. More specifically, these questions addressed whether an individual had received training from health professionals about managing asthma, about recognizing and effectively treating early warning signs of an asthma episode, and about changing their environment to minimize the risk of attacks. These variables included:
- Ever taken class on managing asthma (ASTHCLASS, in 1991, 1998, 1999, 2003, 2008, 2013)
- Talk with health professional about managing asthma (ASTHMANAGE, in 2003, 2008)
- Ever taught to recognize early signs of asthma episode (ASTHSIGNS, in 2003, 2008, 2013)
- Ever taught how to respond to asthma episode (ASTHRESPOND, in 2003, 2008, 2013)
- Ever taught to monitor peak flow for daily therapy (ASTHPEAK, in 2003, 2008, 2013)
- Shown how to use inhaler (ASTHINSHOW in 2003, 2008)
- Ever given an asthma management plan (ASTHPLAN, in 2002-2003, 2008, 2013)
- Ever advised to change environment for asthma (ASTHCHEN, in 2002-2003, 2008, 2013)
- Followed advice to change environment for asthma (ASTHCHENYES, in 2003, 2008)
Available in 1991 only, ASTHMAYR identifies sample persons who reported that they had asthma during the past 12 months.
In 2007, LUNGPROBYR indicates whether sample children were ever diagnosed by a doctor or other health professional as having lung or breathing problems, other than asthma.
Comparability of ASTHMAEV over time is affected by changes including the 2019 redesign. Along with universe changes, the question wording for ASTHMAEV changed slightly over time. In 1988, interviewers asked, "Did--ever have asthma?" (in the child's survey only). In 1993, interviewers asked, "Have you ever been told by a doctor that you have asthma?" Beginning in 1997, interviewers asked, "Have you ever been told by a doctor or other health professional that you had asthma?"
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.
- 1988: Sample persons under 18.
- 1993: Half of sample persons age 18+ in quarters 3 and 4 (excluded from AIDS supplement).
- 1997-2018: Sample adults age 18+ and sample children under age 18.
- 2019-2021: Sample adults age 18+ and sample children age 0-17.
- 1988, 1993, 1997-2021