The International Study of Asthma and Allergies in Childhood (ISAAC): rational methods and outlook

Despite considerable research little is known about the etiology of asthma and allergic disease. The International Study of Asthma and Allergies in Childhood (ISAAC) was developed to maximize the value of epidemiological research into asthma and allergies by establishing standardized methods and international collaboration. The aims of ISAAC are: to describe the prevalence and severity of asthma, rhinitis, and eczema in children living in different centres, and to make comparisons within and between countries; to obtain baseline measures for assessment of future trends in the prevalence and severity of these diseases; and to provide a framework for further etiological research into genetic, lifestyle, environmental, and medical care factors affecting these diseases, The collaborative study has 3 phases, Phase I was developed to assess the prevalence and severity of asthma and allergic disorders among children in many populations worldwide, The standardized study protocol has been completed successfully in 155 centers on all 5 continents. The great variability in living conditions between the study centers is ideal for ecologic analyses of determinants of disease in populations. First articles on the worldwide variation in prevalence of these diseases will be published soon.