1. Endocrinology Laboratory, Department of Clinical ChemistryAmsterdam Gastroenterology & Metabolism, Amsterdam UMC, University of Amsterdam Amsterdam The Netherlands
2. Reference Laboratory Neonatal Screening, Center for Health protectionNational Institute for Public Health and the Environment Bilthoven The Netherlands
3. Section Metabolic Diagnostics, Department of GeneticsUniversity Medical Center Utrecht Utrecht The Netherlands
4. Department of Clinical ChemistryIsala Hospital Zwolle The Netherlands
5. Department of Clinical ChemistryElisabeth‐Tweesteden Hospital Tilburg The Netherlands
6. Translational Metabolic Laboratory, Department of Laboratory MedicineRadboud University Medical Center Nijmegen The Netherlands
7. Department of Pediatrics, Division of Metabolic DisordersAmsterdam UMC, Vrije Universiteit Amsterdam Amsterdam The Netherlands
8. Department of Pediatrics and Clinical GeneticsMaastricht University Medical Center Maastricht The Netherlands
9. Division of Metabolic Disorders, Beatrix Children's HospitalUniversity Medical Center Groningen, University of Groningen Groningen The Netherlands
10. Wilhelmina Children's HospitalUniversity Medical Center Utrecht Utrecht The Netherlands
11. Department of Pediatrics, Division of Metabolic DisordersRadboud University Medical Center Nijmegen The Netherlands
12. Center for Lysosomal and Metabolic diseases, Department of PediatricsErasmus Medical Center Rotterdam The Netherlands
13. Endocrinology Laboratory, Department of Clinical ChemistryAmsterdam Gastroenterology & Metabolism, Amsterdam UMC, Vrije Universiteit Amsterdam Amsterdam The Netherlands
14. Department of Clinical ChemistryIJsselland Hospital Capelle aan den IJssel The Netherlands
15. Department of Pediatrics, Division of Metabolic DisordersAmsterdam UMC, University of Amsterdam Amsterdam The Netherlands