[1] Johns Hopkins Asthma & Allergy Ctr, Div Clin Immunol & Allergy, Baltimore, MD USA
[2] Johns Hopkins Asthma & Allergy Ctr, Div Pulm & Crit Care Med, Baltimore, MD USA
[3] Univ Genoa, Osped Policlin San Martino, DIMI Dept Internal Med, Allergy & Resp Dis, Genoa, Italy
[4] Univ Florence, Azienda Osped Univ Careggi, Immunoallergol Unit, Florence, Italy
[5] UCLouvain, Clin Univ St Luc, Dept Pulm Med, Brussels, Belgium
[6] UCLouvain, Inst Expt & Clin Res, Brussels, Belgium
[7] GSK, Biostat, Stevenage, Herts, England
[8] GSK, Real World Study Delivery, Value Evidence & Outcomes, Global Med, Stevenage, Herts, England
[9] GSK, Value Evidence & Outcomes, Collegeville, PA USA
[10] GSK, Epidemiol, London, England
[11] GSK, Specialty Care TA, Global Med, Brentford, England
[12] Alpha Med Res, Mississauga, ON, Canada