参考方法测定血清葡萄糖的测量不确定度评价

Application of reference method in evaluation of measurement uncertainty of serum glucose

目的探讨参考实验室对测量不确定度的评定方法和程序。方法应用美国疾病与预防控制中心推荐的血清葡萄糖测定参考方法对血清样本进行测定，分析整个过程中各不确定度分量的来源，按A、B两类不确定度的计算方式对各分量分别进行评定，计算合成标准不确定度。最后取95％置信区间，计算出扩展不确定度。结果血清葡萄糖的平均浓度为1520mmol／L，合成标准不确定度为0．14mmol／L，取95％置信区间，包含因子k=2，则扩展不确定度￡，为0．29mmol／L。结论参考实验室的测量不确定度与传统的测量误差相比，更能反映测量的水平，对临床检验工作有一定的指导意义，也为采用标准曲线法定量的，如血清葡萄糖、血清总胆红素和血清尿素等参考方法测量结果的不确定度评价提供一定的科学依据。

Objective To explore the method and procedure for evaluation of measurement uncertainty of serum glucose in reference laboratory. Methods The concentration of glucose in serum samples was measured by the reference method which was recommended by the U. S. Centers for Disease Control and Prevention （CDC）, and the sources of each uncertainty compo- nent in whole procedure of analysis were identified. The evaluation of uncertainty components was processed by using two types of method, then a combined standard uncertainty was calculated; finally, an expanded uncertainty was given according to 95% confidence interval. Results The average concentration of glucose was 15.20 mmol/L, the related combined standard uncer- tainty was 0.14 mmol/L and the expanded uncertainty（U） was 0.29 mmol/L （the desired level of confidence of approximately 95%, the coverage factor k=2）. Conclusion Compared to the traditional measurement errors, the measurement uncertainty in refer- ence laboratory may reflect the measurement ability better, and which would be helpful for evaluation of measurement uncertainty in reference laboratory.