1. Paediatric Neurosciences Unit, Royal Hospital for Children, Glasgow, UK
2. Department of Pediatrics and Neurology, Cincinnati Children's Hospital, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
3. Department of Neurology, University Hospital Essen, Essen, Germany
4. Headache Science Center, IRCCS C. Mondino Foundation, Pavia, Italy
5. Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy