1 Department of Paediatrics, MDUK Oxford Neuromuscular Centre & NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, UK. laurent.servais@paediatrics.ox.ac.uk.
2 Division of Child Neurology, Department of Pediatrics, Centre de Référence des Maladies Neuromusculaires, University Hospital Liège and University of Liège, Liège, Belgium. laurent.servais@paediatrics.ox.ac.uk.
3 SYSNAV, Paris, France.
4 Department of Neurology, Centre de Référence des Maladies Neuromusculaires, University Hospital Liège and University of Liège, Liège, Belgium.
5 Dubowitz Neuromuscular Centre, NIHR Great Ormond Street Hospital Biomedical Research Centre, Great Ormond Street Institute of Child Health, University College London, London, UK.