1. Nuffield Department of Clinical Neurosciences; John Radcliffe University Hospital; University of Oxford; Oxford United Kingdom
2. Department of Pediatric Neurology; Erasmus Medical Center; Rotterdam The Netherlands
3. Department of Pediatrics; Leiden University Medical Center; Leiden The Netherlands
4. Departments of Pediatric Neurology and Neurology; Canisius Hospital; Nijmegen The Netherlands
5. Department of Neurology; University Medical Center Groningen; University of Groningen; Groningen The Netherlands