MEASURING THE PREVALENCE OF BRONCHIAL HYPERRESPONSIVENESS IN CHILDREN

Background. The aim of this study was to assess the effectiveness of a n asthma prevalence video questionnaire (involving the audiovisual pre sentation of clinical asthma), a standard written questionnaire (based on the IUATLD Bronchial Symptoms Questionnaire) and a new written que stionnaire (designed for an international study of asthma and allergie s in childhood [ISAAC]) in predicting bronchial hyper-responsiveness ( BHR) (PD20 less than or equal to 7.8 mu mol methacholine). Methods. Th e IUATLD and video questionnaires were administered to 193 schoolchild ren (13-16 years). The ISAAC questionnaire was administered to 87 of t hese children. All children subsequently underwent bronchial challenge to methacholine. Results. The sensitivity and specificity for predict ing BHR were similar for individual questions from the IUATLD and vide o questionnaires, The Video questions with the highest Youden's index related to moderate wheezing at rest (0.46), severe wheezing at rest ( 0.38), and nocturnal wheezing (0.37). The ISAAC questionnaire was simi lar in effectiveness to the IUATLD questionnaire in predicting BHR. Co nclusions. The video questionnaire is a valid method of assessing the prevalence of BHR, and may be particularly useful when comparing popul ations with differing languages and cultures. Some video questions app eared more effective than others in relation to predicting BHR. A new written questionnaire (ISAAC) designed for a large international asthm a prevalence study in children also is an effective method for measuri ng the prevalence of BHR.