Initial test of the Seattle Asthma Severity and Control Questionnaire: a multidimensional assessment of asthma severity and control

Background: The Seattle Asthma Severity and Control Questionnaire (SASCQ) was designed as a short, sensitive, and quantitative measure of asthma severity, impairment, and risk. Objectives: To evaluate the distribution of responses to the SASCQ in a diverse asthma population and to determine whether the questionnaire is associated with other measures of asthma severity and control. Methods: A cross-sectional study of 188 asthmatic patients was conducted in a large academic primary care network. Asthma severity was confirmed in a subgroup of 44 patients by means of an in-person interview and lung function measurement. Results: The SASCQ score had a nearly normal distribution across the heterogeneous population and less of a floor effect than the number of asthma-free days. The SASCQ score showed a higher symptom burden in the mildest asthmatic patients compared with nonasthmatic controls. Asthma severity evaluated using the questionnaire was correlated with asthma severity evaluated by means of in-person interview and with controller medication class. The SASCQ score was associated with primary care visits for asthma, emergency department treatment for asthma, days missed from work, and confidence to control asthma symptoms; the associations between these measures of impairment and risk were all stronger for the SASCQ score than for asthma-free days. Conclusions: The SASCQ is a quantitative measure of asthma that accurately discriminates between established levels of asthma severity and that is associated with other measures of asthma control and risk. Ann Allergy Asthma Immunol. 2009; 103:225-232.