1. Pediatric Endocrinology and Hormone Laboratory University Children’s Hospital Tübingen Germany
2. Institute for Clinical Epidemiology and Applied Biometry University Hospital of Tübingen Tübingen Germany
3. Screening‐Labor Hannover Hannover Germany
4. Department of Clinical Chemistry Hannover Medical School Hannover Germany
5. Department of Neonatology University Children's Hospital Tübingen Germany