International Study of Asthma and Allergies in Childhood (ISAAC): rationale and methods

TLDR

Asthma and allergic disease etiology remains poorly understood despite extensive research. ISAAC was established to standardize epidemiological research on asthma and allergic disease, aiming to describe prevalence and severity across countries, set baseline measures for trend assessment, and provide a framework for etiological studies of genetic, lifestyle, environmental, and medical factors. ISAAC comprises three phases: Phase 1 uses core questionnaires to assess prevalence and severity; Phase 2 investigates etiological factors suggested by Phase 1; Phase 3 repeats Phase 1 to assess trends.

Abstract

The aetiology of asthma and allergic disease remains poorly understood, despite considerable research. The International Study of Asthma and Allergies in Childhood (ISAAC), was founded to maximize the value of epidemiological research into asthma and allergic disease, by establishing a standardized methodology and facilitating international collaboration. Its specific aims are: 1) 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; 2) to obtain baseline measures for assessment of future trends in the prevalence and severity of these diseases; and 3) to provide a framework for further aetiological research into genetic, lifestyle, environmental, and medical care factors affecting these diseases. The ISAAC design comprises three phases. Phase 1 uses core questionnaires designed to assess the prevalence and severity of asthma and allergic disease in defined populations. Phase 2 will investigate possible aetiological factors, particularly those suggested by the findings of Phase 1. Phase 3 will be a repetition of Phase 1 to assess trends in prevalence.