1. 1 Department of Medical Laboratory Diagnostics , Clinical Hospital “Sveti Duh” , Zagreb , Croatia
2. 2 Department of Nursing , Umeå University , Umeå , Sweden
3. 3 Department of Laboratory Medicine , Paracelsus Medical University , Salzburg , Austria
4. 4 BD Life Sciences – Preanalytical Systems , Reading , UK
5. 5 Department of Clinical Biochemistry , Worcester Acute Hospitals NHS Trust , Worcester , UK
6. 6 Department of Clinical Chemistry , Academic Medical Center , Amsterdam , The Netherlands
7. 7 Ümraniye Research and Training Hospital , Istanbul , Turkey
8. 8 Clinic for Otorhinolaryngology and Maxillofacial Surgery, Clinical Center of Serbia , Belgrade , Serbia
9. 9 Department of Medical Biosciences , Clinical Chemistry, Umeå University , Umeå , Sweden
10. 10 Department of Clinical Pathology , São João Hospital Center, Department of Biomedicine, Faculty of Medicine , Porto , Portugal ; and EPI Unit, Institute of Public Health , University of Porto , Porto , Portugal
11. 11 National Association of Phlebotomists , London , UK
12. 12 Department of Clinical Laboratory , University Hospital Arnau de Vilanova , Lleida , Spain .
13. 13 Greiner Bio-One GmbH , Kremsmuenster , Austria
14. 14 Clinical Laboratory Diagnostic and Pathomorphology Department , Autonomous non-profit organization of additional professional education “Institute of Laboratory Medicine” , Moscow , Russia
15. 15 Norwegian quality improvement of laboratory examinations , Bergen , Norway
16. 16 Section of Clinical Biochemistry, University of Verona , Verona , Italy ; and Latin American Working Group for Preanalytical Phase (WG-PRE-LATAM) of the Latin America Confederation of Clinical Biochemistry (COLABIOCLI) , Verona , Italy
17. 17 Section of Clinical Chemistry , University of Verona , Verona , Italy
18. 18 Institute of Laboratory Medicine, Kliniken Nordoberpfalz AG and Klinikum St. Marien , Weiden and Amberg , Germany
19. 19 Clinical Biochemistry and Pharmacology , Odense University Hospital , Odense , Denmark
20. 20 West Hertfordshire Hospitals NHS Trust, Operating UK NEQAS for Haematology and Transfusion , Watford , UK
21. 21 Sarstedt GmbH & Co.KG , Nümbrecht , Germany
22. 22 Center for Medical Biochemistry, Clinical Center of Serbia , Belgrade , Serbia
23. 23 Department of Laboratory Medicine , University of Leuven , Leuven , Belgium