1. 1Clinic of Gastroenterology and Endocrinology, University Medical Center Goettingen, Goettingen, Germany
2. 2Endokrinologikum Goettingen, Goettingen, Germany
3. 3Interdisciplinary Pediatric Center for Children with Developmental Disabilities and Severe Chronic Disorders, University Medical Center Goettingen, Goettingen, Germany
4. 4Endokrinologikum Hamburg, Hamburg, Germany
5. 5Endokrinologikum Berlin, Berlin, Germany
6. 6Endokrinologikum Hannover, Hannover, Germany
7. 7Endokrinologikum Frankfurt, Frankfurt/Main, Germany