[1] Univ Bergen, Inst Global Publ Hlth & Primary Hlth Care, Norwegian Qual Improvement Primary Care Labs Nokl, Bergen, Norway
[2] Lab Clin Biochem, Bergen, Norway
[3] Univ Dundee, Ninewells Hosp & Med Sch, Ctr Res Canc Prevent & Screening, Dundee DD1 9SY, Scotland
[4] Univ Sydney, Sch Publ Hlth, Prince Wales Hosp, SEALS Dept Clin Chem,Screening & Test Evaluat Pro, Sydney, NSW 2006, Australia
[5] Univ New S Wales, Sch Med Sci, Sydney, NSW, Australia
[6] Radboud Univ Nijmegen, Netherlands Fdn Qual Assessment Med Labs SKML, NL-6525 ED Nijmegen, Netherlands
[7] St Vincents Hosp, SydPath, Sydney, NSW 2010, Australia
[8] Atrium Orbis, Dept Clin Chem & Haematol, Heerlen, Netherlands
[9] Commiss European Communities, Joint Res Ctr, Inst Reference Mat & Measurements, Geel, Belgium
[10] Son Healthcare, Melbourne, Vic, Australia
[11] Univ Melbourne, Melbourne, Vic, Australia
[12] Univ Milan, Ctr Metrol Traceabil Lab Med CIRME, Milan, Italy