Development of an add-on module for the WHOQOL-BREF on patients with allergic rhinitis

The purpose of this study was to develop an add-on module for the Taiwan-version WHOQOL-BREF for assessing the quality of life of people with allergic rhinitis. A cross-sectional survey design was used. In accordance with the seven steps for the development of population-specific modules of the WHOQOL, the instrument added new items on the basis of opinions of expert groups, including patients, families and physicians, to the Taiwan-version WHOQOL-BREF measure. The new questionnaire, comprising 52 items, was tested on 252 patients with allergic rhinitis. For content validity, each item was significantly correlated with the domain to which it belonged (r = .157-.715, p < .05); and each domain was significantly correlated with each other domain (r = .211-.535, p < .01). The construct validity was examined by means of the multitrait-multimethod method. The total score and the scores on the physiological and environmental subscales showed convergent validity with the score for IgE (r = -.317--.380, p < .01) and with the total score and the scores on the subscale of the allergic rhinitis symptom questionnaire (r = -.202--.360, p < .01). The scores on the body constitution subscale also showed convergent validity with the score for IgE (r = .329, p < .01) and with the total score and the scores on the subscale of the allergic rhinitis symptom questionnaire (r = .187-.261, p < .01). This result supports the appropriateness of this new questionnaire specifically for assessing the quality of life of people with allergic rhinitis. As regards concurrent validity, the total score was significantly correlated with the score of all subscales in the Medical Outcomes Study Short Form Taiwan-version (SF-36) (r = .256-.542, p < .01). The internal consistency reliability established by Cronbach's alpha ranged for each domain from .73-.81. The test-retest reliability correlated for each domain of the instrument was .719-.794 (p < .01). In conclusion, the add-on module developed in this paper for the Taiwan-version WHOQOL-BREF for patients with allergic rhinitis is reliable, valid and specific.