1. Department of Clinical Biochemistry and Pharmacology , Odense University Hospital , Sdr. Boulevard 29 , Odense 5000 , Denmark
2. Department of Laboratory Medicine , Paracelsus Medical University , Salzburg , Austria
3. Department of Clinical Chemistry , Worcestershire Acute Hospitals NHS Trust , Worcester , UK
4. Laboratorio Clínico Hospital La Paz , Madrid , Spain
5. Department of Medical Biosciences, Clinical Chemistry, Umeå University , Umeå , Sweden