The International Study of Asthma and Allergies in Childhood (ISAAC) is the largest epidemiological allergy study ever conducted. Phase II recruited 28,951 children aged 8-12 years from 28 study centers to evaluate the prevalence and risk factors of allergic disease. Children were skin-prick tested for environmental allergens and examined for flexural eczema. A questionnaire tool was used to determine eczema prevalence. It was thought that allergen skin sensitization was an epiphenomenon of disease activity rather than a uniform cause of flexural eczema. The questionnaire was adequate at population level but less so at individual risk factor level (Flohr, C. 5th Int Symp Atopic Dermat (May 11-13, Kyoto) 2008. Abst 5.1C). --> -->