1. Research Department, Young Epilepsy, Lingfield, Surrey, United Kingdom;
2. Child Development Centre, Crawley Hospital, Crawley, West Sussex, United Kingdom;
3. Neurosciences Unit, Institute of Child Health, University College London, London, United Kingdom;
4. Great Ormond Street Hospital for Children NHS Trust, London, United Kingdom;
5. Muir Maxwell Epilepsy Centre, Edinburgh Neurosciences, The University of Edinburgh, Edinburgh, United Kingdom;
6. Gillberg Neuropsychiatry Centre, University of Gothenburg, Gothenburg, Sweden; and
7. College of Medicine, University of Vermont, Burlington, Vermont