1. Department of Paediatrics, Faculty of Medicine and University Hospital Cologne, University of Cologne , 50937 Cologne , Germany
2. Institute of Epidemiology and Medical Biometry, ZIBMT, University of Ulm , 89081 Ulm , Germany
3. Pediatric Endocrinology, University-Children's Hospital Tübingen, 72076 Tübingen , Germany
4. Department of Pediatrics, Klinikum Wels-Grieskirchen , 4600 Wels , Austria
5. Department of Pediatrics, Technical University of Munich, TUM School of Medicine , 80804 Munich , Germany
6. Department of Pediatrics, University Hospital Münster , 48149 Münster , Germany
7. Division of Pediatric Pulmology, Allergology and Endocrinology, Department of Pediatrics, Medical University of Vienna , 1090 Wien , Austria
8. Department of Pediatrics, St. Anna Kinderspital, Medical University of Vienna , 1090 Wien , Austria
9. Department of Pediatrics and Adolescent Medicine, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nuremberg , 91054 Erlangen , Germany