[1] Univ Ulm, Inst Epidemiol, D-89081 Ulm, Germany
[2] Univ London Imperial Coll Sci Technol & Med, Natl Heart & Lung Inst, London, England
[3] Chinese Univ Hong Kong, Prince Wales Hosp, Dept Paediat, Shatin, Hong Kong, Peoples R China
[4] Ctr Invest FEPIS, Quininde, Ecuador
[5] Tallinn Childrens Hosp, Tallinn, Estonia
[6] Ctr Allergy & Immunol, Tbilisi, Georgia
[7] Hannover Med Sch, Ctr Paediat, Clin Pneumol & Neonatol, D-3000 Hannover, Germany
[8] Univ Munich, Dr von Haunersches Kinderspital, Munich, Germany
[9] Local Hlth Author Rome, Dept Epidemiol, Rome, Italy
[10] Wellington Sch Med & Hlth Sci, Wellington Asthma Res Grp, Wellington, New Zealand
[11] Norwegian Inst Publ Hlth, Div Epidemiol, Oslo, Norway
[12] AL Quds Univ, Fac Publ Hlth, Jerusalem, Israel
[13] Torrecardenas Hosp, Pediat Pulmonol Unit, Almeria, Spain
[14] Arrixaca Univ, Childrens Hosp, Pediat Allergy Unit, Murcia, Spain
[15] Arrixaca Univ, Childrens Hosp, Pulmonol Unit, Murcia, Spain
[16] CIBER Epidemiol & Publ Hlth CIBERESP, Murcia, Spain
[17] 12 Octubre Childrens Hosp, Pediat Allergy & Pneumol Unit, Madrid, Spain
[18] Univ Valencia, Dept Prevent Med & Publ Hlth, CIBER Epidemiol & Publ Hlth CIBERESP, Valencia, Spain
[19] Univ Valencia, Fdn Invest, Dr Peset Univ Hosp, Valencia, Spain
[20] Linkoping Univ Hosp, Fac Hlth Sci, Allergy Ctr, S-58185 Linkoping, Sweden
[21] Sundsvall Hosp, Dept Publ Hlth & Res, Sundsvall, Sweden
[22] Hacettepe Univ, Fac Med, Dept Pediat Allergy & Asthma, TR-06100 Ankara, Turkey
[23] Univ London, London, England