临床化学实验室质量控制计算实际西格玛值的新方法  

New Method for Calculating the Actual Sigma Metrics in Clinical Chemistry Laboratory Quality Control

作　　者：王辉[1] 徐克和[1] 唐书强[1] 黄亨建[1] WANG Hui;XU Ke-he;TANG Shu-qiang;HUANG Heng-jian(Department of Laboratory Medicine,the West China Hospital of Sichuan University,Chengdu 610041,China)

机构地区：[1]四川大学华西医院实验医学科,成都610041

出　　处：《现代检验医学杂志》2019年第2期132-136,共5页Journal of Modern Laboratory Medicine

基　　金：四川省科技厅(2017SZ0063和2014SZ0170)

摘　　要：目的计算实际西格玛(sigma,σ)值,正确评估实验室检测项目分析性能。方法方法①结合室内质量控制(internal quality control,IQC),与室间质量评价(external quality assessment,EQA),计算westgard两种σ计算公式■和■下的σ_1与σ_2值。以IQC累积均值χ_1与EQA靶值μ_2的比值(χ_1/μ_2)为横轴,σ_1,σ_2为纵轴绘制散点图,比较σ_1,σ_2的关系;方法②以伯乐公司全球质控材料,批号为45751和45753,仪器为罗氏Cobas 8000全自动生化分析仪,累积到2018年1月份的均值作为靶值μ_1,结合IQC数据计算Westgard两种公式下检测项目的σ_1,σ_2值。结果方法①计算的σ_1与σ_2值并不相同,甚至相差很大,而且对钠(Na)、氯(Cl)、钙(Ca)三个TEa要求高的检测项目,σ值计算结果为负值。比较σ_1,σ_2的关系,当χ_1/μ_2<1时,σ_1>σ_2;当χ_1/μ_2>1时,σ_1<σ_2。方法②中χ_1/μ_1值接近于1,σ_1,σ_2大小非常接近。结论结合IQC与EQA计算σ时,应选取与质控材料同一浓度水平的测定值,这才能真实反映实验室检测项目分析性能。Objective To calculate the actual sigma metrics(σ)and correctly evaluate analytical performance of tests.Methods Method①combined internal quality assessment(IQC)with external quality assessment(EQA),σ1andσ2of twoσcalculation formulas of westgard were calculated:σ1=TEa-bias/s andσ2=TEa%-bias%/CV%.The ratio of cumulative meanχ1of IQC to target valueμ2of EQA(χ1/μ2)were plotted on the horizontal axis,andσ1andσ2were plotted on the vertical axis.The relationship betweenσ1andσ2were compared.Method②was based on the quality control materials from Bio-Rad laboratory with batch numbers of 45 751and 45 753.The instrument was the Roche Cobas 8 000automatic biochemical analyzer.The average value accumulated in January 2018was taken as the target valueμ1.The IQC data was used to calculateσ1andσ2of tests using Westgard formula.Resultsσ1andσ2calculated by method①were different,and theσvalue were negative for tests with high TEa requirements such as Na,Cl and Ca.In the relationship ofσ1andσ2,whenχ1/μ2<1,σ1>σ2;whenχ1/μ2>1,σ1<σ2.In the method②,the value ofχ1/μ1was close to 1,and the values ofσ1andσ2were very close.Conclusion When calculatingσby combining IQC and EQA.The measured value at the same concentration level as the quality control material should be selected,which can truly reflect analytical performance of tests.

关 键 词：六西格玛 质量控制 

分 类 号：R446[医药卫生—诊断学]