1. Laboratory Medicine Ospedale San Raffaele Milan, Italy
2. Working Group on Biological Variation European Federation of Clinical Chemistry and Laboratory Medicine http://efcclm.eu/science/wg-biological-variation
3. Clinical Laboratory Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milan, Italy
4. Laboratory of Clinical Biochemistry Haukeland University Hospital Bergen, Norway
5. Norwegian Quality Improvement of Laboratory Examinations (Noklus) Haraldsplass Deaconess Hospital Bergen, Norway
6. Department of Global Health and Primary Care Faculty of Medicine University of Bergen Bergen, Norway
7. Department of Laboratory Medicine La Paz University Hospital Madrid, Spain
8. Acibadem Mehmet Ali Aydinlar University School of Medicine Atasehir, Istanbul, Turkey