1. Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
2. Department of Clinical Chemistry, Universitair Ziekenhuis Brussel, Brussels, Belgium
3. Department of Diabetology, Hôpital Universitaire des Enfants Reine Fabiola, Brussels, Belgium
4. Department of Endocrinology, Universitair Ziekenhuis Leuven, Leuven, Belgium
5. Department of Endocrinology, Diabetology and Metabolism, Universitair Ziekenhuis Antwerpen, Antwerp, Belgium
6. Department of Diabetology, Universitair Ziekenhuis Brussel, Brussels, Belgium