[1] UCL Inst Child Hlth, Great Ormond St Hosp, Neurosci Unit, London WC1N 2AP, England
[2] Natl Ctr Young People Epilepsy, London, England
[3] Royal Hosp Sick Children, Dept Paediat Neurosci, Edinburgh EH9 1LF, Midlothian, Scotland
[4] Birmingham Childrens Hosp NHS Fdn Trust, Dept Paediat Neurol, Birmingham, W Midlands, England
[5] Evelina Childrens Hosp, Guys & St Thomas NHS Fdn Trust, Dept Paediat Neurol, London, England