1. Department of Pain Medicine BG University Hospital Bergmannsheil GmbH Ruhr University Bochum Germany
2. Department Internal and Integrative Medicine Faculty of Medicine Kliniken Essen‐Mitte University of Duisburg‐Essen Germany
3. Health Care Center for Pain Medicine and Mental Health Saarbrücken Germany
4. Department Internal Medicine I Klinikum Saarbrücken Germany
5. Department Psychosomatic Medicine and Psychotherapy Technische Universit€at Müunchen Germany