1. Section of Health Care Research and Rehabilitation Research, Institute of Medical Biometry and Statistics, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
2. Deutsche Rentenversicherung Rheinland-Pfalz (German Statutory Pension Insurance Rhineland Palatinate), Mittelrhein-Klinik (Clinic for Psychosomatic Rehabilitation), Boppard-Bad Salzig, Germany
3. Section of Rehabilitation Psychology and Psychotherapy, Department of Psychology, University of Freiburg, Freiburg, Germany