[1] GlaxoSmithKline Inc, Res Triangle Pk, NC 27709 USA
[2] Univ Sheffield, Acad Unit Resp Med, Sheffield, S Yorkshire, England
[3] Kommune Hosp Copenhagen, Inst Prevent Med, Copenhagen, Denmark
[4] Hvidovre Univ Hosp, Dept Resp Med, DK-2650 Hvidovre, Denmark
[5] Ullevaal Univ Hosp, Dept Pediat, Oslo, Norway
[6] N Staffordshire Hosp, Acad Dept Pediat, Directorate Child Hlth, Stoke On Trent, Staffs, England
[7] Univ Leicester, Div Child Hlth, Leicester, Leics, England
[8] Univ Aberdeen, Royal Aberdeen Childrens Hosp, Dept Child Hlth, Aberdeen, Scotland