1. Internal Medicine, Department of Endocrinology; Departments of University Medical Center Groningen, Groningen, The Netherlands.
2. Laboratory Medicine, University Medical Center Groningen, Groningen, The Netherlands.
3. Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, Groningen, The Netherlands.
4. Molecular Endocrinology Laboratory, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom.
5. Division of Endocrinology, Department of Internal Medicine, Maastricht University Medical Center, Maastricht, The Netherlands.
6. Princess Máxima Center for Pediatric Oncology, Utrecht, The Netherlands.
7. Department of Pediatric Oncology, Sophia Children's Hospital; Rotterdam, The Netherlands.
8. Surgical Oncology, and University Medical Center Groningen, Groningen, The Netherlands.
9. Brandenburg Medical School, Institute of Biostatistics and Registry Research, Neuruppin, Germany.
10. Department of Pediatrics, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands.
11. Epidemiology; University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
12. Division of Endocrinology, Department of Internal Medicine, Leiden University Medical Center, Leiden, The Netherlands.
13. Division of Endocrinology, Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands.
14. Department of Internal Medicine; Erasmus Medical Center, Rotterdam, The Netherlands.
15. Erasmus MC Academic Center for Thyroid Disease, Rotterdam, The Netherlands.
16. Division of Endocrinology, Department of Internal Medicine, Amsterdam UMC, VU University Medical Center, Amsterdam, The Netherlands.
17. Pediatric Endocrinology, University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, Groningen, The Netherlands.
18. Paediatric Oncology, University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, Groningen, The Netherlands.