Austrian Association for Quality Assurance and Standardization of Medical and Diagnostic Tests (ÖQUASTA), University Hospitals Birmingham NHS Foundation Trust, UK National External Quality Assessment Scheme (UK NEQAS) for Haematology, Centre Toulousain pour le Contrôle de qualité en Biologie clinique (CTCB), Royal College of Pathologists of Australasia Quality Assurance Program, Independent, Paracelsus Medical University Salzburg - Salzburger Landeskrankenhaus, Laboratoire National de Métrologie et d’Essais (LNE), Medical University of Vienna - Vienna General Hospital, Reference Institute for Bioanalytics, The Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), Medical University of Innsbruck - University Hospital of Innsbruck, ESEAP – Proficiency Testing Scheme for Clinical Laboratories, Royal College of Pathologists of Australasia Quality Assurance Program, LGC, Ltd., ESEAP – Proficiency Testing Scheme for Clinical Laboratories, Careggi University Hospital of Florence, The Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), Columbia University - New York Presbyterian, The Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), INSTAND e.V. Society for Promoting Quality Assurance in Medical Laboratories, Radboud University - Radboud University Medical Center, University of British Columbia (UBC) - Department of Pathology and Laboratory Medicine and University of British Columbia (UBC) - Department of Pathology and Laboratory Medicine

Austrian Association for Quality Assurance and Standardization of Medical and Diagnostic Tests (ÖQUASTA), UK National External Quality Assessment Scheme (UK NEQAS) for Haematology, University Hospitals Birmingham NHS Foundation Trust, Instituto de Salud Pública de Chile, Centre Toulousain pour le Contrôle de qualité en Biologie clinique (CTCB), Royal College of Pathologists of Australasia Quality Assurance Program, Independent, Leiden University Medical Centre, Sciensano, Laboratoire National de Métrologie et d’Essais (LNE), National Health Institute Doutor Ricardo Jorge (INSA), Reference Institute for Bioanalytics, Medical University of Innsbruck - University Hospital of Innsbruck, LGC, Ltd., University of Szeged, Reference Institute for Bioanalytics, Medical University of Vienna - Vienna General Hospital, External Quality Control for Assays and Tests (ECAT) Foundation, National Health Institute Doutor Ricardo Jorge (INSA), UK National External Quality Assessment Scheme (UK NEQAS) Immunology, Immunochemistry & Allergy (IIA), Careggi University Hospital of Florence, The Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), Tirol Kliniken GmbH, Medical University of Vienna - Vienna General Hospital, QMD Services, INSTAND e.V. Society for Promoting Quality Assurance in Medical Laboratories, University of Ulsan - Asan Medical Center, Radboud University - Radboud University Medical Center, Queen Beatrix Regional Hospital, NGO AQALM, Institut für Qualitätssicherung in der Virusdiagnostik - IQVD GmbH, University of British Columbia (UBC) - Department of Pathology and Laboratory Medicine and University of British Columbia (UBC) - Department of Pathology and Laboratory Medicine

Austrian Association for Quality Assurance and Standardization of Medical and Diagnostic Tests (ÖQUASTA), Medical University of Vienna - Center for Virology, Austrian Agency for Health and Food Safety GmbH (AGES), Austrian Agency for Health and Food Safety GmbH (AGES), Medical University of Vienna - Center for Virology, Austrian Association for Quality Assurance and Standardization of Medical and Diagnostic Tests (ÖQUASTA), Austrian Association for Quality Assurance and Standardization of Medical and Diagnostic Tests (ÖQUASTA), Karl Landsteiner Institute for Clinical Risk Management, Austrian Association for Quality Assurance and Standardization of Medical and Diagnostic Tests (ÖQUASTA), Austrian Association for Quality Assurance and Standardization of Medical and Diagnostic Tests (ÖQUASTA), University of Vienna - Faculty of Computer Science, Medical University of Vienna - Center for Virology, Medical University of Vienna - Center for Virology and Center for Virology

Austrian Association for Quality Assurance and Standardization of Medical and Diagnostic Tests (ÖQUASTA), UK National External Quality Assessment Scheme (UK NEQAS) for Haematology, University Hospitals Birmingham NHS Foundation Trust, Centre Toulousain pour le Contrôle de qualité en Biologie clinique (CTCB), Royal College of Pathologists of Australasia Quality Assurance Program, FTC Forensic Toxicology Laboratory, MVZ Ärztliche Laboratorien München-Land GmbH, Independent, Laboratoire National de Métrologie et d’Essais (LNE), KU Leuven, FTC Forensic Toxicology Laboratory, Reference Institute for Bioanalytics, Erasmus University Rotterdam (EUR), LGC, Ltd., NGO AQALM, INSTAND e.V. Society for Promoting Quality Assurance in Medical Laboratories, GBD Gesellschaft für Biotechnologische Diagnostik mbH, Reference Institute for Bioanalytics, KU Leuven, Technische Universität München (TUM), Swiss Center for Quality Control (CSCQ), Technology University of Braunschweig, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń - Department of Laboratory Medicine, Careggi University Hospital of Florence, RISE Research Institutes of Sweden, The Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), Paul-Ehrlich-Institut, University of Ljubljana - University Medical Centre Ljubljana, INSTAND e.V. Society for Promoting Quality Assurance in Medical Laboratories, The Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), Radboud University - Radboud University Medical Center, Medical University Vienna, Institut für Qualitätssicherung in der Virusdiagnostik - IQVD GmbH, University of British Columbia (UBC) - Department of Pathology and Laboratory Medicine and University of British Columbia (UBC) - Department of Pathology and Laboratory Medicine

Austrian Association for Quality Assurance and Standardization of Medical and Diagnostic Tests (ÖQUASTA), University Hospitals Birmingham NHS Foundation Trust, UK National External Quality Assessment Scheme (UK NEQAS) for Haematology, Centre Toulousain pour le Contrôle de qualité en Biologie clinique (CTCB), EQALM Virtual Microscopy Working Group, Royal College of Pathologists of Australasia Quality Assurance Program, Labquality, Independent, Leiden University Medical Centre, Sciensano, Laboratoire National de Métrologie et d’Essais (LNE), Reference Institute for Bioanalytics, Medical University of Innsbruck - University Hospital of Innsbruck, Rigshospitalet Glostrup, LGC, Ltd., University of Szeged, University of Szeged, Technische Universität München (TUM), External Quality Control for Assays and Tests (ECAT) Foundation, Labquality, Careggi University Hospital of Florence, The Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), INSTAND e.V. Society for Promoting Quality Assurance in Medical Laboratories, Radboud University - Radboud University Medical Center, Institut für Qualitätssicherung in der Virusdiagnostik - IQVD GmbH, University of British Columbia (UBC) - Department of Pathology and Laboratory Medicine and University of British Columbia (UBC) - Department of Pathology and Laboratory Medicine

Austrian Association for Quality Assurance and Standardization of Medical and Diagnostic Tests (ÖQUASTA), University Hospitals Birmingham NHS Foundation Trust, UK National External Quality Assessment Scheme (UK NEQAS) for Haematology, Centre Toulousain pour le Contrôle de qualité en Biologie clinique (CTCB), Royal College of Pathologists of Australasia Quality Assurance Program, Labquality, Independent, Sciensano, Laboratoire National de Métrologie et d’Essais (LNE), Reference Institute for Bioanalytics, Medical University of Innsbruck - University Hospital of Innsbruck, Rigshospitalet Glostrup, LGC, Ltd., Labquality, Technische Universität München (TUM), Careggi University Hospital of Florence, The Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), INSTAND e.V. Society for Promoting Quality Assurance in Medical Laboratories, Radboud University - Radboud University Medical Center, University of British Columbia (UBC) - Department of Pathology and Laboratory Medicine and University of British Columbia (UBC) - Department of Pathology and Laboratory Medicine