1. Clinic of Gastroenterology and Gastrointestinal Oncology University Medical Center Goettingen Goettingen Germany
2. Endokrinologikum Saarbruecken Saarbruecken Germany
3. MVZ Endokrinologikum Goettingen Goettingen Germany
4. Institute for Medical Statistics, University Medical Center Goettingen Goettingen Germany
5. Department for Psychosomatic Medicine and Psychotherapy University Medical Center Goettingen Goettingen Germany