Recommendations for Setting a Criterion and Assessing Commutability of Sample Materials Used in External Quality Assessment/Proficiency Testing Schemes

It is important that external quality assessment materials (EQAMs) are commutable with patient samples, i.e. they behave like patient samples when measured using end-user clinical laboratory in vitro diagnostic medical devices (IVD-MDs). Using commutable EQAMs makes it possible to evaluate metrological traceability and/or equivalence of results between IVD-MDs. The criterion for assessing commutability of an EQAM is that its result should be within the prediction interval limits based on the statistical distribution of the relationship between the clinical sample results from the two IVD-MDs being compared. The width of the prediction interval is dependent on the analytical performance characteristics of the IVD-MDs. A pre-supposition for using this criterion is that the differences in nonselectivity between the two IVD-MDs being compared are acceptable. An acceptable difference in nonselectivity should be small relative to the analytical performance specifications used in the EQA scheme. The acceptable difference in nonselectivity is used to modify the prediction interval criterion for commutability assessment. The present report provides recommendations on how to perform a commutability assessment of EQAMs, how to establish a criterion for acceptable commutability and how to establish the difference in nonselectivity that can be accepted between IVD-MDs. The report also contains applications for performing a commutability assessment of EQAMs in practice.

SANDBERG Sverre;  FAUSKANGER Pernille;  JOHANSEN Jesper V.;  KELLER Thomas;  BUDD Jeffrey;  GREENBERG Neel;  REJ Robert;  PANTEGHINI M.;  DELATOUR Vincent;  CERIOTTI Ferruccio;  DEPREZ Liesbet;  CAMARA Johanna E;  MACKENZIE Finlay;  LYLE Alicia;  VAN DER HAGEN Elina;  BURNS Chris;  MILLER W. Greg; 

2023-11-21

OXFORD UNIV PRESS INC

JRC133296

0009-9147 (online),   

https://doi.org/10.1093/clinchem/hvad135,    https://publications.jrc.ec.europa.eu/repository/handle/JRC133296,   

10.1093/clinchem/hvad135 (online),