A category 1 EQA scheme for comparison of laboratory performance and method performance: An international pilot study in the framework of the Calibration 2000 project.
BACKGROUND
In the modern healthcare service, patients receive care in multiple hospitals and healthcare settings. Therefore, harmonization of results from different methods and instruments, both between and within laboratories, is of the utmost importance. The present pilot study aims to test the use of a Category 1 EQA scheme across four European countries by assessing the current level of equivalence of test results.


METHODS
This work was led by the Dutch External Quality Assurance Scheme SKML and involved 28 laboratories from three regions in the UK, Spain and Portugal, and 120 laboratories from The Netherlands. A set of six commutable samples, targeted with reference methods, were circulated and 18 biochemistry analytes were tested.


CONCLUSIONS
The Total Error (TE) score, defined as the probability (%) that results are within the Total Error Acceptable (TEA) limits, for the eighteen analytes was calculated. Our data show that there is a need for further harmonization of laboratory data, in particular for electrolytes (calcium, chloride, magnesium, sodium), enzymes (ALT, amylase, AST, LDH), lipids (HDL-cholesterol), and for substrates (creatinine, total protein). Lack of performance consistency between instruments was seen for most analytes. The lack of harmonization is still present despite manufacturer claims of established traceability.
Dutch Foundation for Quality Assessment in Medical Laboratories (SKML), Nijmegen, The Netherlands. Electronic address: office@skml.nl.
Rob
R
Jansen
Department of Clinical Biochemistry, Harrogate District Foundation Trust, Harrogate, UK.
Nuthar
N
Jassam
WEQAS Quality Laboratory, Cardiff and Vale University Health Board, Cardiff, UK.
Annette
A
Thomas
Spanish Society of Clinical Chemistry and Molecular Pathology (SEQC), Analytical Quality Commission, Spain.
Carmen
C
Perich
Spanish Society of Clinical Chemistry and Molecular Pathology (SEQC), Analytical Quality Commission, Spain.
Pilar
P
Fernandez-Calle
Instituto Nacional de Saude, Portugal.
Ana Paula
AP
Faria
Instituto Nacional de Saude, Portugal.
Helena
H
Correia
Blood Sciences, Old Medical School, Leeds Teaching Hospitals Trust, Leeds, UK.
Julian H
JH
Barth
Dutch Foundation for Quality Assessment in Medical Laboratories (SKML), Nijmegen, The Netherlands.
Cas
C
Weykamp
Department of Clinical Chemistry, Leiden University Medical Center, Leiden, The Netherlands.
Christa
C
Cobbaert
Department of Clinical Chemistry and Hematology, Amphia Hospital, Breda, The Netherlands.
Marc
M
Thelen
Spanish Society of Clinical Chemistry and Molecular Pathology (SEQC), Analytical Quality Commission, Spain.
Carmen
C
Ricós
D002138:Calibration; D019411:Clinical Laboratory Techniques / Q000592:standards*; D005060:Europe; D006801:Humans; D010865:Pilot Projects; D011785:Quality Assurance, Health Care / Q000379:methods*; D013223:Statistics as Topic
Biological variation; Commutability; External quality assessment; Harmonization; Reference method; Traceability