Application of quality control chart to internal quality control of qualitative detection by real-time PCR
Objective To explore the feasibility of the quality control chart used as an internal quality control method of nucleic acid qualitative detection by real-time PCR and the control chart used cycle threshold(CT)as test values.Meth-ods All batches of SARS-CoV-2 samples from the laboratory between December 2022 and March 2023 were collected,and the samples were tested for SARS-CoV-2 using real-time fluorescent quantitative PCR.A normal distribution test was conducted on the CT values of the 2 target genes in the results of the weak positive quality control samples.According to the first 20 tests,the mean value((x)),standard deviation(s)and coefficient of variation(CV)of ORF1ab gene CT val-ues and N gene CT values were calculated respectively and the quality control charts were plotted.The control chart was drawn with"(x)±2 s"warning limit,"(x)±3 s"control limit and was used to analyze the positive quality control results retrospectively.Results The CT values of ORF1ab gene and N gene fitted a normal distribution.The quality control re-sults of 118 batch tests were plotted with"13,"out of control for 8 times in ORF1ab gene chart and with"13s"out of con-trol for 6 times,"10(x)"out of control for 1 time in N gene chart.Conclusion The application of the control chart to in-ternal quality control is feasible in the process of nucleic acid qualitative detection by real-time PCR and could effectively monitor the abnormal accidents in the tests and is helpful for the test system in a continuous stability.
Control chartInternal quality controlReal-time quantitative PCRLaboratory detection
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NSTL
万方数据
