Item responsiveness of a rhinitis and asthma symptom score during a pollen season

Twenty-one asthma patients with allergic rhinitis completed a series of self-administered questionnaires (21-item symptom score for rhinosinusitis and asthma, bother scale, McMaster Asthma Quality of Life Questionnaire [MAQOL] and Euroqol) at 2-week intervals from August to November 1994. Relative responsiveness of the instruments was assessed in reference to the maximum and minimum average scores for MAQOL, with area under the curve (AUC) and correlation coefficients between the different instruments. Symptom score, MAQOL, and bother scale provided similar results for both extreme values and AUC, whereas Euroqol utilities were less responsive. These results suggest that the symptom scores and bother scales are responsive and valid, and might prove valuable in everyday practice, clinical trials, and quality assurance programs.