1. Medical Psychology and Medical Sociology; Integrated Research and Treatment Center AdiposityDiseases, Leipzig University Medical Center; Leipzig Germany
2. Department of General Surgery; Asklepios Clinic; Hamburg Germany
3. Schön Klinik Hamburg Eilbek Bariatric Clinic; Hamburg Germany
4. Department of General, Visceral, Vascular and Pediatric Surgery; University Hospital, University of Würzburg; Würzburg Germany
5. Department of Visceral, Pediatric and Vascular Surgery; Hospital Konstanz; Konstanz Germany