Investigations on the effect of measuring value transfer for human serum samples assigned by the reference laboratory network / 临床检验杂志

ABSTRACT

Objective To investigate the effect of measuring value transfer for human serum samples assigned by the reference laboratory network on improving the trueness of seven enzyme activities in clinical laboratories,such as ALT,AST,GGT,LDH,CK,AMY and ALP.Methods Depending on the medical imtitutions at all levels contacted by 5 reference laboratories in North China,South China,East China and Southwest China,the corresponding clinical laboratory measuring value transfer/traceability network was established.The frozen human serum samples with good interehangeability and standard material characteristics,including calibrator,sample 1 and sample 2,were provided by Beijing Aerospace General Hospital,and were assigned by 5 reference labotatories in four regiom.These samples were sent to 48 clinical laboratories.These clinical laboratories measured sample 1 and sample 2 according to their standard operating procedures,and then measured.the two samples again after adjusting their measurement system by using the supplied calibrator.The changes of trueness of detection results in these laboratories were evaluated according to the WS/T 403-2012 standard,and the changes of consistency for ALT and AST before and after measuring value tramfer were investigated.Results The results of AMY,ALP,GGT,CK and LDH calibrator,sample 1 and sample 2 assigned by the established network were 138.7 U/L,278.5 U/L and 68.3 U/L,265.3 U/L,94.5 U/L and 134.4 U/L,195.8 U/L,89.0 U/L and 158.9 U/L,393.7 U/L,260.0 U/L and 645.3 U/L,and 302.0 U/L,250.0 U/L and 452.7 U/L,respectively.The percentages of sample 1 and sample 2 which met the bias requirements of the WS/T 403-2012 standard before measuring value transfer for AMY,ALP and GGT were 65.9％ and 61.0％,76.6％ and 78.7％,and 66.7％ and 70.8％,respectively,while after measuring value transfer,they were 89.2％ and 83.8％,86.7％ and 80.0％,and 85.4％ and 91.7％,respectively.The percentages of sample 2 which met the bias requirements of the WS/T 403-2012 standard before measuring value transfer for CK and LDH were 64.6％ and 58.3％,respectively,while after measuring value trander,they were 93.5％ and 84.8％,respectively.The coefficients of variation (consistency) of sample 1 and sample 2 for ALT and AST before measuring value tramfer were 12.9％ and 11.3％,and 10.2％ and 8.9％,respectively,while after measuring value transfer,they were 9.3％ and 8.2％,and 5.6％ and 5.9％,respectively.Conclusion The calibration of routine measurement systems based on the measuring value transfer for human serum samples assigned by the reference laboratory network may improve the comparability of 7 enzyme actvities measurement results in chnical laboratories at all levels obviously,which deserves to be further spread.