Sensitivity and specificity of asthma definitions and symptoms used in a survey of childhood asthma

We compared the ability of definitions/symptoms of asthma to identify urban , elementary schoolchildren with physician-diagnosed asthma and bronchial h yperresponsiveness (BHR) post-exercise challenge. Definitions of asthma fro m the literature were compared, including American Thoracic Society (ATS) a nd British Medical Research Council (BMRC) definitions. Modified ATS had th e highest sensitivity (77%), whereas BMRC had the highest specificity (99%) . The most sensitive symptom was "wheeze with cold" (89%). The most specifi c symptoms were "medication required," and "breathing normal between attack s" (95%). Definitions and symptoms were poor predictors of BHR. Researchers can use these estimates in selecting and defining specific populations of children with asthma.