1. Department of Laboratory Medicine, Paracelsus Medical University, Salzburg, Austria
2. Clinical Chemistry Department, Worcestershire Acute Hospitals NHS Trust, Worcester, UK
3. Department of Medical Laboratory Diagnostics, University Hospital Sveti Duh, Zagreb, Croatia
4. UK NEQAS Haematology, West Hertfordshire Hospitals NHS Trust, operating UK NEQAS for Haematology and Transfusion, Watford, UK
5. Norwegian Quality Improvement of laboratory examinations (Noklus), Bergen, Norway
6. Department of Clinical Pathology, São João Hospital Center, Department of Biomedicine, Faculty of Medicine, and EPI Unit, Institute of Public Health, University of Porto, Porto, Portugal
7. Department of Medical Biosciences, Clinical Chemistry, Umea University, Umea, Sweden
8. Clinical Department of Laboratory Medicine, University Hospitals Leuven, Leuven, Belgium
9. Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark
10. Department of Clinical Chemistry, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
11. Department of Laboratory Medicine, University Hospital Arnau de Vilanova, IRBLleida, Lleida, Spain
12. Institute of Laboratory Medicine, Kliniken Nordoberpfalz AG and Klinikum St. Marien, Weiden and Amberg, Germany
13. Section of Clinical Chemistry, University of Verona, Verona, Italy