1. Pain Centre , Pain Research Group, Odense University Hospital , Odense , Denmark
2. Department of Clinical Research, Faculty of Health Sciences , University of Southern Denmark , Odense , Denmark
3. Department of Anesthesiology and Intensive Care , Vejle and Middelfart Hospitals, University Hospital of Southern Denmark , Odense , Denmark
4. Department of Regional Health Research , University of Southern Denmark , Odense , Denmark
5. Department of Anesthesiology and Intensive Care , Odense University Hospital , Odense , Denmark
6. Department of Rheumatology , The Parker Institute, Copenhagen University Hospital , Frederiksberg , Denmark
7. Department of Anaesthesiology, Multidisciplinary Pain Centre , Vejle and Middelfart Hospitals, University Hospital of Southern , Odense , Denmark