Westgard西格玛规则在糖化血红蛋白检验项目室内质量控制中的选择应用

目的 运用Westgard西格玛规则帮助临床实验室选择适合糖化血红蛋白(HbA1C)检验项目的室内质量控制(质控)规则。方法 在参加2015年卫生部临床检验中心HbA1C室间质量评价(EQA)和室内质控(IQC)计划的所有实验室中按地区(华北、华中、华东等)随机选取10家,把每家实验室在EQA计划中的百分差值当作其偏倚(bias)的估计值,在IQC计划中的累积变异系数当作其不精密度(CV)的估计值。以生物学变异导出的适当要求、美国病理家学会(CAP)、中国EQA计划中的允许总误差(TEa)作为质量规范,利用公式σ=(TEa-|bias|)/CV]计算σ值,结合Westgard西格玛规则为各实验室HbA1C检验项目选择正确的质控规则。结果 使用基于生物学变异的TEa,各实验室σ值均<2,应选1_3s/2_2s/R_4s/4_1s/规则。使用源自CAP的TEa,2号实验室σ值为5.04,应选1_3s/2_2s/R_4s规则; 其余实验室σ值均<4,应选1_3s/2_2s/R_4s/4_1s/规则。使用我国EQA计划可接受限作为TEa,2号实验室σ值>6,应选1_3s规则; 1号实验室σ值为5.45,应选1_3s/2_2s/R_4s规则; 6,10号实验室σ值分别为4.76和4.18,应选1_3s/2_2s/R_4s/4_1s规则; 其余实验室σ值均<4,应选1_3s/2_2s/R_4s/4_1s/规则。结论 临床实验室可以运用简便快捷的Westgard西格玛规则为检验项目选择正确的质控规则。

Application of Westgard Sigma Rules in Selecting Internal Quality Control Rules for Hemoglobin A1C Tests

Objective To help clinical laboratories to select internal quality control rules which was adapt to HemoglobinA1C(HbA1C)testsby the use of Westgard Sigma Rules.Methods Randomly chose 10 clinical laboratories in accordance with region(Northern China,Central China,Eastern China,et al)from all participants that attended both HbA1C external quality assessment(EQA)and internal quality control(IQC)schemes in 2015.The percentage difference in the external quality assessment scheme was viewed as the estimation value of bias,while the accumulated coefficient of variation in the internal quality control scheme was used as the estimation value of imprecision.Using the total allowable errors based upon desirable requirements from biological variation.College of American Pathologists(CAP)and EQA scheme of China as the quality specification,calculating sigma value by the equation σ=(TEa-|bias|)/CV] and then combining Westgard Sigma Rules to choose proper quality control rules for HbA1C tests in every laboratory.Results Using the total allowable error based upon biological variation as quality specification,1_3s/2_2s/R_4s/4_1s/multi-rules were selected for all laboratories whose sigma values were less than 2.If the total allowable error derived from CAP was used,No.2 laboratory(the number represents the corresponding laboratories in the following)should choose1_3s/2_2s/R_4smultirules due to its sigma value 5.04and other laboratories whose sigma values were less than 4 should choose 1_3s/2_2s/R_4s/4_1s/multi-rules.When the total allowable error from acceptable limits of Chinese EQA sheme was employed,No.2 laboratory with sigma value more than 6 had to select 1_3s rule,No.1 laboratory with sigma value 5.45 should make achoice of 1_3s/2_2s/R_4s multirules,and 1_3s/2_2s/R_4s/4_1s multirules were suitable option for No.6 and No.10 laboratory whose sigma values were 4.76 and 4.18,respectively.In addition,1_3s/2_2s/R_4s/4_1s/multi-rules were selected for other laboratories whose sigma values were less than 4.Conclusion Due to theconvenience and rapidness,clinical laboratories can take advantage of WestgardSigma Rules to correctly choose quality control rules.