[1] Univ Bern, Inst Social & Prevent Med, Bern, Switzerland
[2] Univ Bern, Bern, Switzerland
[3] Univ Bern, Bern Univ Hosp, Div Paediat Resp Med, Dept Paediat,Inselspital, Bern, Switzerland
[4] Kantonsspital Aarau, Dept Paediat, Aarau, Switzerland
[5] Univ Zurich, Univ Childrens Hosp Zurich, Dept Resp Med, Zurich, Switzerland
[6] Univ Zurich, Childrens Res Ctr, Zurich, Switzerland
[7] Cantonal Hosp Lucerne, Childrens Hosp, Div Paediat Pulmonol, Luzern, Switzerland
[8] Paediat Practice, Worb, Switzerland
[9] Univ Childrens Hosp Basel UKBB, Zurich, Switzerland
[10] Univ Bern, Bern Univ Hosp, Div Paediat Resp Med & Allergol, Dept Paediat, Bern, Switzerland