[1] Univ Hosp Southampton NHS Fdn Trust, Dept Child Hlth, Southampton, Hants, England
[2] UCL, Inst Child Hlth, London, England
[3] Bambino Gesu Pediat Hosp, Dept Neurosci, Rome, Italy
[4] Klinikum Kassel, Neuropaediat, Kassel, Germany
[5] Vall dHebron Univ Hosp, Dept Paediat Neurol, Barcelona, Spain
[6] BresMed Hlth Solut, Sheffield, S Yorkshire, England
[7] Shire, Zug, Switzerland
[8] Katholieke Univ Leuven, Univ Hosp, Pediat Neurol, Leuven, Belgium