摘要目的 对不同检测系统HBV DNA测定结果进行不确定度评定和量值溯源,探讨不同检测系统HBV DNA测定结果的可比性,为实验室检验结果互认和实验室认可提供实验数据.方法 以国家标准物质作为"正确性质控物质",参考NATA颁布的"化学测量结果不确定度评定与报告导则",对不同检测系统HBV DNA测定结果的不确定度进行评定,并将结果溯源至国家标准物质;根据CLSI的EP9-A2文件要求,对不同检测系统HBV DNA测定结果进行比对分析和偏差评估,以检测系统偏倚的不确定度(ub)作为判断依据,将t(0.05sv)√u2b1+u2b2作为临床可接受的判断标准,评价不同检测系统HBV DNA测定结果的可比性.结果 3个检测系统测定HBV DNA国家标准物质所得的均值(-y)不同,分别为6.15、5.88、6.31,除检测系统A的偏倚无统计学意义(P＞0.05)外,检测系统B、C的偏倚均具有统计学意义(P均＜0.05);3个检测系统HBV DNA测定结果的扩展不确定度(U)也不同,但均在卫生部临床检验中心室间质量评价中规定的最大允许范围(±0.5)之内.经溯源至国家标准物质后,3个检测系统测定患者样本HBV DNA结果分别为:(5.45±1.23)、(5.55±1.32)、(5.42±1.25)lg(kIU/L),差异具有统计学意义(F=5.63,P＜0.05).3个检测系统测定结果两两比较显示,检测系统A与C比较,测定结果差异无统计学意义(q=1.85,P＞0.05);检测系统A与B比较,测定结果差异有统计学意义(q=5.12,P＜0.05);检测系统B与C比较,测定结果差异有统计学意义(q=6.85,P＜0.05).3个检测系统中,任意两个检测系统间HBV DNA测定结果的偏差均无统计学意义(P均＞0.05),表明检测系统间测定结果的偏差临床可以接受,测定结果具有可比性.结论 当不同实验室HBV DNA检验结果进行比较与互认时,应对各检测系统进行不确定度评定和量值溯源,并对不同检测系统间测定结果进行偏差评估,判断其临床可接受性,以保证检验结果的准确性和可比性.

abstractsObjective To study the uncertainty and traceability of HBV DNA assays and discuss the comparability of results among different detection systems. Methods Different detecting systems were used to detect HBV DNA using the national standard substance as "quality control substance". The uncertainty of the results was evaluated referring "Guidelines for estimating and reporting measurement uncerTAinty of chemical test results" of NATA The results were traced back to the national standard substance. According to the CLSI document EP9-A2, the results were analyzed and subjected to bias estimation with the t(0.05sv) √u2b1+ u2b2 as the criterion clinically accepted to investigate the comparability of different detecting systems. Results The means (-y) measured by 3 HBV DNA assay systems were 6.15,5.88,and 6.31 lg(kIU/L) respectively. Except system A,both the biases of system B and C had statistical significance (all P ＜ 0. 05) and expanded uncertainty of three detection systems was varied, but the difference was within the maximum acceptable range (± 0. 5) of the external quality assessment by National Center for Clinical Laboratory. Being traceable to national standard substance, the results of HBV DNA of the three detecting systems were (5.45 ± 1.23), (5.55 ± 1.32) and (5.42 ± 1.25) lg(kIU/L), respectively.There was significant difference among three systems (F = 5.63, P ＜ 0. 05). Comparing system A and B,there was significant difference in statistic (q = 5. 12, P ＜ 0. 05) and the difference between system B and C also had statistically significant (q = 6. 85, P ＜ 0. 05), but the results between system A and C had no statistical difference (q = 1.85,P ＞ 0. 05). Among these three systems, the difference of any two detection systems had no statistical significance (all P ＞ 0. 05). It showed that system bias was acceptable in clinical application and the results between different systems were comparable. Conclusions It is necessary to estimate the uncertainty and traceability when comparing the HBV DNA assay among the different labs. It also needs to estimate the bias of different systems and evaluate the clinical acceptability to ensure the accuracy and comparability of the results.