ASST Fatebenefratelli-Sacco - Clinical Pathology Unit, University of Milan - Department of Biomedical and Clinical Sciences, Università degli Studi di Milano-Bicocca - Department of Psychology, ASST Fatebenefratelli-Sacco University Hospital - Department of Infectious Diseases, Medical University of Lodz - Department of Neurology, ASST Fatebenefratelli-Sacco - Clinical Pathology Unit, University of Milan - Department of Biomedical and Clinical Sciences, University of Milan - Department of Biomedical and Clinical Sciences and Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń - Department of 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, 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