1. Department of Psychology and Psychotherapy, University Witten, Herdecke, Germany
2. Medical Psychology and Medical Sociology, Clinic and Policlinic for Psychosomatic Medicine and Psychotherapy, University Medicine, Mainz, Germany
3. Clinic for Orthopaedics and Traumatology, University Hospital Carl Gustav Carus, Dresden, Germany
4. Dresden University of Technology, Department of Internal Medicine III, Dresden, Germany