2项分子生物学诊断指标测量不确定度评定

Evaluation of uncertainty measurement about 2 diagnostic indexes of molecular biology

目的探讨对2项分子生物学诊断指标HBV—DNA及HCV—RNA测量不确定度的评定。方法利用实时荧光定量PCR法检测HBV—DNA及HCV—RNA室内质控及室间质控标本，收集2012年4月至9月工作日内的HBV—DNA及HCV—RNA室内质控数据及2011年至2012年室间质控结果。依据《化学分析中不确定度的评估指南》评定检测项目测量不确定度的准则，计算HBV—DNA及HCV—RNA的批内及批间变异系数，结果总体偏差变异系数，进而计算出HBV—DNA及HCV—RNA标准不确定度及扩展不确定度。结果同一天内16次HBV—DNA室内质控的检测批内变异系数为4．89％，12次HCV—RNA室内质控的检测批内变异系数为2．55％，2012年4月至9月共129天的HBV—DNA检测批问变异系数为9．54％，155天的HCV—RNA检测批间变异系数为5．80％；2011年至2012年卫生部临检中心HBV—DNA及HCV—RNA室间质评共40个检测数据，其结果总体偏差变异系数分别为5，33％和6．12％，剔除检测为零的数据后重新计算变异系数分别为5．83％和7．06％。批内、批问及结果总体偏差的因素合成后，两者的扩展不确定度分别为±24．02％和-4-17．62％，剔除检测为零的数据分别后为±24．41％和±18．97％。结论分子生物学指标检测过程影响因素多，因素间相关程度高，不确定度来源的数学模型定型困难，计算繁复。利用现有室内外质控数据进行测量不确定度评价，可极大简化操作步骤，操作性较强。

Objective To study the evaluation of uncertainty measurement about 2 diagnostic indexes of molecular biology. Methods According to Guidance on Evaluating the Uncertainty in Chemical Analysis Criterion, HBV-DNA and HCV-RNA internal quality control and external quality assessment specimens were detected with real-time fluorescence quantitative PCR assay, then we collected internal quality control data from April to September, 2012, and external quality assessment results from 2011 to 2012. The coefficient of variations about intra-assay, inter-assay and bias were calculated, determined the standard uncertainty and the expanded uncertainty. Results In the same day, the coefficient of variation about intra-assay was 4.89% by detecting 16 HBV-DNA specimens of internal quality control, and that was 2.55% in 12 HCV-RNA detecting; the coefficient of variation of inter-assay was 9.54% by detecting 129 days HBV-DNA specimens of internal qualitycontrol from April to September, 2012, and that was 5.80% by detecting 155 days HCV-RNA specimens of in ternal quality control from April to September, 2012; the coefficient of variation of bias about HBV-DNA and HCV-RNA were 5.33% and 6.12% by detecting 40 external quality assessment specimens distributed by na- tional center for clinical laboratory from 2011 to 2012. After removing the data of zero, the data was recalculated as 5.83% and 7.06%. After synthesized factors about intra-assay, inter-assay and bias, the expanded uncertainty of HBV-DNA and HCV-RNA were 24.02% and 17.62%, and excluding the data of zero, which were 24.41% and 18.97% .Conclusions There were various influencing factors in detecting molecular biology indexes. It is difficult in mathsort and counting. Using the existing data of internal quality control and external quality assessment to evaluate the uncertainty measurement of diagnostic index about molecular biology is a ra- tional way, which is a simple and facile method in clinical laboratory.