应用六西格玛(6σ)模式评价血常规项目的分析性能，并建立血常规项目个性化的质控方案和质量改进措施。

收集本实验室血常规项目2020年江苏省卫健委临检中心室间质评数据及同期室内质控数据，以“适当”生物学变异导出的质量规范作为实验室允许总误差(TEa)，计算各项目的σ值，同时应用标准化的σ性能验证图进行标示。并依据具有批长度的Westgard西格玛规则和质量目标指数(QGI)，分别制定各项目个性化的室内质控方案和质量改进措施。

以生物学变异数据作为质量目标，白细胞计数(WBC)项目的分析性能达到“世界一流”水平，其余项目则处于“临界”至“优秀”之间。依据具有批长度的Westgard西格玛规则，WBC项目选择1_3s规则(N=2)且分析批长度为1 000个患者的样本作为其室内质控方案；红细胞计数(RBC)项目选择1_3s/2_2s/R_4s/4_1s多规则(N=4)且分析批长度为200个患者的样本作为其室内质控方案；血红蛋白(Hb)项目选择1_3s/2_2s/R_4s多规则(N=2)且分析批长度为450个患者的样本作为其室内质控方案；血细胞比容(HCT)和血小板计数(PLT)项目选择1_3s/2_2s/R_4s/4_1s/6_X多规则(N=6)且分析批长度为45个患者的样本作为其室内质控方案。此外，Hb和HCT需要优先改进精密度；RBC和PLT则需同时改进精密度和正确度。

6σ模式能够客观评价临床血常规项目分析性能，其在帮助实验室质控策略的设计和质量改进方面具有重要的指导意义。

Application of six sigma model to evaluate the analytical performance of hematology analytes, aims to establish a personalized quality control schemes and quality improvement measures for hematology analytes.

The data of external quality assessment (EQA) of hematology analytes from Jiangsu center for clinical laboratories in 2020 and its internal quality control (IQC) results were collected. And the quality specification derived from the "desirable" biological variation was used as allowable total error (TEa) to calculate the sigma value of each item. Meanwhile, analytical performance of each item was demonstrated on the standardized sigma performance verification chart. According to the Westgard sigma rules with batch length and the quality goal index (QGI), personalized IQC schemes and quality improvement measures for each item were formulated respectively.

With biological variation data as laboratory quality goal, the analytical performance of the WBC reached the "world-class" level, while the remaining projects ranged from "marginal" to "excellent". According to the Westgard sigma rules with batch length, 1_3s rule (N=2) with batch length of 1 000 patient samples was selected as IQC scheme for WBC. Multi-rules of 1_3s/2_2s/R_4s/4_1s (N=4) with batch length of 200 patient samples was selected as IQC scheme for RBC. Multi-rules of 1_3s/2_2s/R_4s (N=2) with batch length of 450 patient samples was selected as IQC scheme for Hb. Multi-rules of 1_3s/2_2s/R_4s/4_1s/6_x (N=6) with batch length of 45 patient samples was selected as IQC scheme for HCT and PLT. In addition, based on the calculation of QGI, Hb and HCT need priority to improve the precision; While RBC and PLT need to improve both precision and accuracy at the same time.

The six sigma model can objectively evaluate the analysis performance of clinical hematology analytes, which has important guiding significance in helping the design of laboratory quality control strategies and quality improvement.