1. CHU de Liège, Neurology, Headache Research Unit, Citadelle Hospital, Liège, Belgium
2. Rigshospitalet Glostrup, Danish Headache Center, Glostrup, Denmark
3. Leiden University Medical Center, Leiden, Netherlands
4. King’s College London, Headache Group, London, UK
5. Samsung Medical Center, Sungkyunkwan University School of Medicine, Soeul, Republic of Korea
6. Department of Neurology, University of Essen, Essen, Germany
7. Department of Neurology, Mayo Clinic, Scottsdale, Arizona, USA
8. CHU de Nice, Neurosurgery, Nice, France
9. University College London Institute of Neurology, London, UK
10. Universitäts-Krankenhaus Eppendorf, Systems Neuroscience, Hamburg, Germany
11. Vector Psychometric Group, Behaviorial Analytics, Chapel Hill, North Carolina, USA
12. Dartmouth-Hitchcock, Department of Neurology, Lebanon, New Hampshire, USA