六西格玛在凝血项目质量控制方面的应用及改进

Application and improvement of six sigma in quality control of coagulation analytes

目的探讨六西格玛(6σ)在评价凝血项目分析性能上的应用价值。方法收集本实验室凝血项目的2018年国家卫健委临检中心室间质评数据和2018年6—12月的室内质控数据,选用3个不同来源的允许总误差作为本研究质量目标,分别计算各项目的σ水平。同时绘制标准化的西格玛性能验证图,结合具有批长度的Westgard西格玛规则指导制定个性化的质控策略,并计算σ<6的项目的质量目标指数(quality target index,QGI),确定质量改进方案。结果依据国家卫生行业标准,凝血酶原时间(PT)(σ=6.04)分析性能为“世界一流”水平,选择13s规则(N=2)和批长度为1000个患者样本作为质控方案;活化部分凝血活酶时间(APTT)(σ=5.08)和纤维蛋白原(FIB)(σ=5.21)的分析性能达到“优秀”水平,选择13s/22s/R4s(N=2)规则和批长度为450个患者样本作为质控方案;凝血酶时间(TT)(σ=4.60)的分析性能亦达到“良好”等级,选择13s/22s/R4s/41s(N=4)规则和批长度为200个患者样本作为质控方案。依据国家卫生行业标准,APTT需要优先改进精密度,TT和FIB则需要同时改进精密度和正确度。结论6σ能够客观评价实验室指标的分析性能,并指导实验室制定合理质控策略和质量改进方案,进一步提高实验室的检测能力。

Objective To investigate the application of six sigma in evaluating the analytical performance of coagulation analytes.Methods The data of external quality assessment(EQA)from 2018 and the data of internal quality control(IQC)from June to December 2018 were collected.Three different allowable total error(TEa)were selected as quality goals to calculate sigma value of each analyte respectively.Meanwhile,draw a standardized Sigma performance verification chart,combined with Westgard Sigma rules with batch length to guide the development of personalized quality control stategies,and the quality goal index(QGI)of coagulation analytes(sigma<6)were calculated to determine quality improvement plan.Results According to National Health Industry Standards,the analytical performance of prothrombin time(PT)(sigma=6.04)was"world-class"level,and 13s rule(N=2)with batch length of 1000 patient samples were selected as quality control schemes.The analytical performance of activated partial thromboplastin time(APTT)(sigma=5.08)and fibrinogen(FIB)(sigma=5.21)reached"excellent"level,multiple rule of 13s/22s/R4s(N=2)with batch length of 450 patient samples were selected as quality control schemes.The analytical performance thrombin time(TT)(sigma=4.60)also achieved a"good"level,so multiple rule of 13s/22s/R4s/41s(N=4)with batch length of 200 patient samples were selected as quality control schemes.According to National Health Industry Standards,the precision of APTT needs to be improved firstly,the precision and accuracy of TT and FIB need to be improved at the same time.Conclusions Six sigma can objectively evaluate the analytical performance of laboratory indicators,and guide the laboratory to develop reasonable quality control strategies and quality improvement programs,so as to further improve the laboratory detection capabilities.