1. Department of Anesthesiology; Pain and Palliative Medicine; Radboud University Nijmegen Medical Centre; the Netherlands; the Netherlands
2. Department of Guideline Development & Research; Dutch College of General Practitioners (NHG); Utrecht; the Netherlands
3. Department of Special Anesthesiology and Pain Therapy; Medical University /AKH Vienna; Vienna; Austria
4. Department of Neurophysiology; Medical Faculty Mannheim; Heidelberg University; Mannheim; Germany
5. Department of Clinical Pharmacy; Radboud University Nijmegen Medical Centre; Nijmegen; the Netherlands
6. Department of Pain and Palliative Care; University Nice Medical Centre; Nice; France