Comparison and commutability study among four faecal immunochemical tests (FIT) systems

This study aimed to quantify the bias and the correlation between four FIT systems by measuring a panel of 38 faecal samples while limiting the effect of the pre-analytical aspects. In addition, the commutability of seven candidate reference materials (RM) was assessed. Pairwise method comparisons based on faecal samples demonstrated Pearson correlation coefficients ranged between 0.944 and 0.970 and an average proportional bias of -30 to -40% for one FIT system compared to the other three. The relative standard deviation among biases of the individual samples was around 20 to 30 %. Due to these sample specific differences, no decisive conclusions could be drawn in the commutability study. However, two candidate RMs, prepared in the FIT system-specific storage/extraction buffers, had a better commutable profile than the other five. The use of a common threshold for all FIT systems is currently not possible due to the presence of a proportional bias. We have identified potential commutable RMs to take to further studies on the production of a common calibrator, with the aim being to reduce the analytical bias observed on different FIT systems.

DEPREZ Liesbet;  PIGGOTT Carolyn;  VAN DER HAGEN Elina;  FRASA Marieke;  BENTON Sally; 

2023-12-05

WALTER DE GRUYTER GMBH

JRC133310

1434-6621 (online),   

https://www.degruyter.com/document/doi/10.1515/cclm-2023-0278/html,    https://publications.jrc.ec.europa.eu/repository/handle/JRC133310,   

10.1515/cclm-2023-0278 (online),