1. The Generation R Study Group, Erasmus Medical Center—Sophia Children's Hospital, Rotterdam, The Netherlands.
2. Department of Internal Medicine, Erasmus Medical Center—Sophia Children's Hospital, Rotterdam, The Netherlands.
3. Academic Center for Thyroid Diseases, Erasmus Medical Center—Sophia Children's Hospital, Rotterdam, The Netherlands.
4. Department of Clinical Chemistry, Erasmus Medical Center—Sophia Children's Hospital, Rotterdam, The Netherlands.
5. Department of Epidemiology, Erasmus Medical Center—Sophia Children's Hospital, Rotterdam, The Netherlands.
6. Pediatrics, Erasmus Medical Center—Sophia Children's Hospital, Rotterdam, The Netherlands.
7. Pediatric Endocrinology, Wilhelmina Children's Hospital, University Medical Center, Utrecht, The Netherlands.