ABSTRACT
Objective:The allowable total error ( TEa),allowable imprecision ( CV)and allowable bias( Bias)were recommended for 34 routine chemistry analytes in China. Methods:According to the performance specification setting mode newly determined at the Milan conference in Italy,the performance specification was derived based on components biological variation (BV)and current state of the art mode. The data(including EQA data and IQC data)of laboratories participating in the routine chemistry and lipids and lipoproteins EQA activities of the national center for clinical laboratories from 2019 to 2021 was collected through clinet-EQA. For the analytes with biological variation(BV)data,compared the'percentage difference′ of EQA data and the'in-control coefficient of variation of the month′ of IQC data of each research analyte with the three levels evaluation criteria derived based on BV,and calculated the percentage difference passing rate and CV passing rate of all batches in each year. When the passing rate reaches 80%,the performance specifications of this level met the requirements of the recommended performance specifications of the analyte. For the analytes without BV data or analytes whose performance specifications at three levels derived based on BV could not be used as recommended standards,the recommended performance specifications are derived based on the current state of the art. After obtaining the recommended TEa and allowable CV for each analyte,used the formula | Bias|≤ TEa-z? CV to derive the recommended allowable bias. Results:The results of TEa ( CV)% recommended by 34 analytes are as follows:K4.7(2),Na4(1.5),Cl4(1.4),Ca5(2),P9.6(3.9),Glu6.4(2.5),Urea8(3),UA12(4.1),Cre11(3.3),TP5(2),Alb5.2(2.4),TC8.6(2.7),TG13.5(5),HDL-C16.5(4.3),LDL-C20.5(6.2),ApoAⅠ16(5.3),ApoB 17.1(5.5),Lp(a) 24.1(10.4),TBil 12.4(5),DBil 20(7.3),ALT16(5),AST13.5(4.8),ALP17.5(4.8),AMY13.1(3.3),CK11.3(3.8),LDH11(3.9),CHE13.4(5.3),LIP20(6.9),Fe13.3(5.2),Mg14(4.5),Cu17.9(6.8),Zn15.1(6.4),γ-GGT10(3.3),α-HBDH18(5.8).The formula | Bias|≤ TEa-z? CV is used to derive the allowable bias of 34 analytes. Conclusions:For 34 clinical routine chemistry quantitative analytes,the allowable total error,allowable imprecision and allowable bias that meet the current state of the art of Chinese laboratories are recommended.
ABSTRACT
Objective:To establish the allowable total error (TEa) of the national external quality assessment (EQA) program in line with the current quality level of serum folate measurement in China.Methods:The data of serum total folate test in the clinical laboratory of a hospital in Beijing in 2016 were collected, and the Stata SE 15 software was used for Monte Carlo simulation to obtain the false-negative rate under different bias and inaccuracy conditions. The Origin Pro 9.1 software was used to make the contour figure. The TEa of serum total folate test is derived based on the acceptable false-negative rate. National EQA data of serum total folate in 2020 were collected to calculate the pass rate of participating laboratories and the laboratory pass rate of quality control products at each level under the five TEa derived from the analysis performance on clinical outcomes, biological variation, and the evaluation criterion of national EQA.Results:Based on the influence of analytical performance on clinical outcomes, the TEa was 10%. Under this TEa, the pass rate of the first EQA program of serum total folate in 2020 was more than 80%, and the pass rate of the second time was 73.1%. Under the minimum (46.57%) and appropriate level of TEa (15.52%) derived from biological variation and national EQA evaluation criterion, the pass rate of serum total folate in the two EQA programs in 2020 exceeded 85%.Conclusion:The analytical performance of serum total folate in China cannot meet the requirements of TEa derived based on the effect of analytical performance on clinical outcomes. An appropriate level of TEa derived based on biological variation (15.52%) is suggested as the recommended criterion for the TEa of serum total folate test.
ABSTRACT
In the clinical laboratory medicine,the measurement uncertainty (MU)is a relatively new concept.Over the years, experts of clinical laboratory medicine from all over the world made a great number of further researches and promote the development of MU,which led clinical laboratories to pay more and more attention to the meanings and functions of MU at the same time.However,because of the habitual using of the total error (TE)in clinical laboratories and similarities between concepts of MU and TE which easily resulted in confusion,a lot of laboratories still cannot completely accept MU.By explai-ning concepts of TE and MU and analyzing the pros and cons of models of TE and MU as well as their functions,the obj ec-tive of this paper is to help clinical laboratories make further comprehensions of TE and MU and understand how to properly use them in practice.
ABSTRACT
Objective To evaluate the difference of two sources of allowable total errors provided by National Health Industry Standard (WS/T 403-2012,analytical quality specification for routine analytes in clinical biochemistry)and National Stand-ard (GB/T 20470-2006,requirements of external quality assessment for clinical laboratories)in assessing the analytical qual-ity byσmetrics,and selecting quality control procedures using operational process specifications graphs.Methods Selected one of the laboratories participating in the internal quality control activity of routine chemistry of February,2014 and the first time external quality assessment activity of routine chemistry in 2014 organized by National Center for Clinical Labora-tories for its coefficient of variation and the bias of nineteen clinical chemistry tests.With the CV% and Bia%,σmetrics of controls at two analyte concentrations were calculated using two different allowable total errors targets (National Health In-dustry Standard (WS/T 403-2012)and National Standard (GB/T 20470-2006).Could obtain a operational process specifica-tions graph by which Could select quality control procedures using the Quality control computer simulat software developed by National Center for Clinical Laboratories and the company zhongchuangyida.Results The σ metrics under National Health Industry Standard (WS/T 403-2012)were from 0 to 7.Most of the values (86% and 76.2%)under National Stand-ard (GB/T 20470-2006)were from 3 to 15.On the normalized method decision chart,the assay quality using the allowable total errors targets of National Standard (GB/T 20470-2006)was at least one hierarchy more than one using National Health Industry Standard (WS/T 403-2012).The quality control rules under National Health Industry Standard (WS/T 403-2012)were obviously more strict than that under National Standard (GB/T 20470-2006).Among the control procedures using National Health Industry Standard (WS/T 403-2012),multirule (n=4):ALB,ALP,Ca,Cl,TC,Crea,Glu,LDH,K, Na,TP,TG and Urea;13s (n=4):Mg;12.5s (n=2):CK,AMY ang Fe;13s (n=2):TBIL;13.5s (n=2):ALT,AST and UA.Conclusion The allowable total errors provided by National Health Industry Standard (WS/T 403-2012)are more stringent than that from National Standard (GB/T 20470-2006).So Laboratories need to improve the analytical quality of their tests furthermore.