1. Division of Neurological Pain Research and Therapy, Department of Neurology, Universitätsklinikum Schleswig-Holstein, Campus Kiel, Germany;
2. Chair of Neurophysiology, Medical Faculty Mannheim, Heidelberg University, Germany;
3. Department of Neurology, University of Mainz, Germany;
4. Department of Anesthesiology and Pain therapy, St. Josef Hospital, Wuppertal, Germany;
5. Department of Anaesthesiology, Benedictus Hospital Tutzing and Technische Universität München, Germany;
6. Medical Department, Astellas Pharma GmbH, Germany;
7. Institute of Pain Medicine/Pain Practice, Wiesbaden, Germany;
8. Department of Pain Medicine, BG University Hospital Bergmannsheil GmbH, Ruhr-University Bochum, Germany;
9. Department of Palliative Medicine, Medical Faculty RWTH Aachen University, Germany;
10. Department of Neurology, BG-Klinikum Duisburg, Germany;
11. Department of Neurology, University of Würzburg, Germany;
12. Competence Center Chronic Pruritus, Department of Dermatology, University Hospital of Münster, Germany;
13. Department of Neurology, General Hospital Fürth, Fürth, Germany