Vital Signs

Vital Signs: Asthma in Children — United States, 2001–2016

Hatice S. Zahran, MD; Cathy M. Bailey, PhD; Scott A. Damon, MAIA; Paul L. Garbe, DVM; Patrick N. Breysse, PhD


Morbidity and Mortality Weekly Report. 2018;67(5):149-155. 

In This Article


To describe asthma status and to assess trends and demographic differences in self-reported health outcomes, health care use, and asthma care and management among children aged 017 years, CDC analyzed annual core* data (2001–2016) and periodic asthma supplemental data (2003, 2008, and 2013) from the National Health Interview Survey (NHIS).

The NHIS, conducted by CDC's National Center for Health Statistics (NCHS), is a cross-sectional household interview survey of the U.S. civilian noninstitutionalized population in 50 states and the District of Columbia. NHIS uses a multistage, clustered sample design, and applies sampling weights to account for household nonresponse and oversampling of blacks, Hispanics, and Asians to produce national estimates for a variety of health indicators (the sampling design was changed in 2016, and oversampling of these groups was not conducted during that year). NHIS collects additional data on asthma (e.g., routine care visits, hospitalization, missed school days, self-management education, and asthma medication use [rescue and control medications]) every 5 years (i.e., 2003, 2008, and 2013;

In 2016, persons aged 0–17 years accounted for 11,107 of NHIS respondents, including 960 (8.3%) who had current asthma. Children were considered to have current asthma if proxy adults answered "yes" to the following two questions: "Has a doctor or other health professional ever told you that [child] had asthma?" and "Does [child] still have asthma?".[3,4] Trends in prevalence of current asthma (asthma) and asthma attack were assessed. Among children with asthma, demographic (age, sex, race/ethnicity, income status, and U.S. Bureau of the Census geographic region) differences in self-reported school absenteeism, asthma attack, and health care use because of asthma (routine care visit, ED/UC visit, and hospitalization) in the past 12 months were assessed. Prevalences of asthma attack and ED/UC visit were defined as the percentage of children with current asthma who experienced an asthma attack and had an ED/UC visit because of an asthma attack in the past 12 months, respectively. School absenteeism was defined as one or more missed school days by a child aged 5–17 years in the past 12 months. NHIS 2003, 2008, and 2013 data were also analyzed to assess changes in health care use (asthma-related routine care visit and hospitalization in the past 12 months) and asthma care status (ever received any of the 6-component asthma self-management education,§ and asthma medication use [rescue medication and asthma control medication] in the past 3 months). Additional information is available at

Statistical software was used for analysis to account for the complex sampling design. Trends in prevalence of current asthma and asthma attack during 2001–2016 were assessed using Joinpoint software from the National Cancer Institute (NCI),[8] which characterizes trends as joined linear segments. All stated comparisons between demographic groups were evaluated by using two-sided significance tests with statistical significance defined as p<0.05. Relative standard error (RSE), defined as standard error divided by prevalence estimate, was used as a measure of an estimate's reliability (an RSE <0.30 indicates a reliable estimate).[3]

*Core data include sociodemographic characteristics and information on health conditions, health care access and utilization, health behaviors and risk factors.
Supplemental modules collect data on new topics or more detailed information on core topics; can change from year to year; and are designed to meet department goals and objectives.
§The 6-component asthma self-management education includes 1) having been given an action plan, 2) having taken a class to learn how to manage asthma, 3) having been taught to recognize early signs and symptoms of an asthma attack, 4) having been taught how to respond to an asthma attack, 5) having been taught to use a peak flow meter, and 6) having received advice on environmental control.