Validation of the asthma impact survey, a brief asthma-specific quality of life tool
The Asthma Impact Survey (AIS-6) is a new six question asthma outcome tool for which information on validity has not been published. To provide validation for the AIS-6 as a brief asthma-specific quality of life tool. Surveys were sent to a random sample of members of a large managed care organization who were at least 35 years of age and in the two-year period preceding the survey had either (1) at least one documented asthma-related medical encounter, or (2) at least a 6 months supply of asthma medication dispensed. In addition to the AIS-6, the survey included a validated quality of life tool [the mini-Asthma Quality of Life Questionnaire (AQLQ)]; a validated asthma control questionnaire [the Asthma Therapy Assessment QuestionnaireTM (ATAQ)]; a validated symptom severity scale (AOMS); and information regarding demographics, co-morbidities, asthma severity, and asthma management. The results of the AIS-6 were compared to the results of the other tools by means of correlation and factor analysis. Independent predictors of AIS-6 and AQLQ scores were determined by multiple stepwise linear regression analyses. AIS-6 scores were significantly related to female sex, educational level, income, smoking, body mass index (BMI), COPD, steroid use, and hospitalization history in bivariate analyses. The AIS-6 score significantly correlated (r =  − 0.84, p < 0.0001) with the AQLQ total score and loaded on the three factors (activity, symptoms, and concern/bother) reflected by the survey information and on which the AQLQ also loaded. Significant but somewhat smaller correlations were found between the AIS-6 and the ATAQ (r = 0.70, p < 0.0001) and the AOMS (r = 0.55, p < 0.0001). Independent predictors were the same for the AIS-6 and AQLQ and included oral steroid use, COPD history, BMI, female sex, educational level, and hospitalization in the past year. These data support the validity of the short six-question AIS-6 as an asthma-specific quality of life tool.