RT Journal Article
SR Electronic
T1 Phase II of the International Study of Asthma and Allergies in Childhood (ISAAC II): rationale and methods
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 406
OP 412
DO 10.1183/09031936.04.00090303
VO 24
IS 3
A1 Weiland, S.K.
A1 Björkstén, B.
A1 Brunekreef, B.
A1 Cookson, W.O.C.
A1 von Mutius, E.
A1 Strachan, D.P.
A1 the International Study of Asthma and Allergies in Childhood Phase II Study Group
YR 2004
UL http://erj.ersjournals.com/content/24/3/406.abstract
AB International comparative studies, investigating whether disease incidence or prevalence rates differ between populations and, if so, which factors explain the observed differences, have made important contributions to the understanding of disease aetiology in many areas. In Phase I of the International Study of Asthma and Allergies in Childhood (ISAAC), the prevalence rates of symptoms of asthma, allergic rhinitis and atopic eczema in 13–14-yr-olds, assessed by standardised questionnaires, were found to differ >20-fold between the 155 study centres around the world. Phase II of ISAAC aims to identify determinants of these differences by studying informative populations. A detailed study protocol was developed for use in community-based random samples of children aged 9–11 yrs. The study modules include standardised questionnaires with detailed questions on the occurrence and severity of symptoms of asthma, allergic rhinitis and atopic eczema, their clinical management, and a broad range of previous and current exposure conditions. In addition, standardised protocols were applied for examination of flexural dermatitis, skin-prick testing, bronchial challenge with hypertonic saline, blood sampling for immunoglobulin E analyses and genotyping, and dust sampling for assessment of indoor exposures to allergens and endotoxin. To date, ISAAC II field work had been completed or started in 30 study centres in 22 countries. The majority of centres are in countries that participated in International Study of Asthma and Allergies in Childhood Phase I and reflect almost the full range of the observed variability in Phase I prevalence rates. The coordination and central laboratory analyses of the European centres were supported by the Fifth Framework Programme of the European Commission, Brussels, Belgium (QLK4-CT-1999-01288). Support details for the local studies are given in the Funding of local studies section at the end of this article. Pharmacia Diagnostics (Uppsala, Sweden) generously made reagents available at a nominal cost. ALK (Horsholm, Denmark) generously provided reagents for fieldwork in several low-income countries without charge.