摘要
目的用测量不确定度表示指南(GUM)与蒙特卡洛法(MCM)评定本室条件下国际临床化学与检验医学联合会(IFCC)37℃肌酸激酶(CK)参考测量程序的不确定度,比较两种评定结果并尝试寻找适用的酶学参考测量不确定度评定模式。方法按照IFCC参考方法测定样品RELA2012KSA中CK活性水平,寻找测定过程中各不确定度来源,确定本室酶学参考测量模型。用GUM法与MCM法评定3次测量结果的不确定度,并以自适应MCM法对GUM法结果进行验证。结果本室实验条件下,CK活性测定不确定度来源主要有修正后的反应速率、总体积比、样品复溶体积、比色皿光径、摩尔吸光系数、反应温度与pH值及监测波长的偏离等。CK单次测定GUM法不确定度评定结果为(260.0±12.2)U/L,相对扩展不确定度为4.7%,3次测定结果的95%概率对称包含区间分别为(247.829 5,272.094 7)U/L、(246.938 8,270.923 6)U/L、(246.495 1,269.857 5)U/L,均值的不确定度评定结果为(259.0±7.0)U/L,相对扩展不确定度为2.7%。3次CK测定MCM法不确定度评定结果为输出量估计值,分别为260.0、259.0、258.2 U/L,95%概率对称包含区间分别为(248.753 2,271.535 7)U/L、(247.746 9,270.418 0)U/L、(247.303 9,269.330 8)U/L。用MCM法验证GUM法包含区间,3组绝对偏差dlow与dhigh值均大于数值容差0.05,GUM法结果未通过MCM法验证。结论 MCM法结果更为准确,可用于结果报告。GUM法结果经MCM法验证其质量后,可用于发现各不确定度来源对参考测量质量的影响,提高实验室质量改进效率。联合应用GUM法与MCM法进行不确定度评定可作为酶学参考测量不确定度评定方案的一种选择。
Objective To evaluate uncertainty in measurement of catalytic activity concentrations of creatine kinase（ CK） at 37 ℃ using Guide to the Expression of Uncertainty in Measurement（ GUM） uncertainty framework and Monte Carol method（ MCM） according to IFCC primary reference procedure under the conditions of our laboratory,compare the results of GUM with MCM and try to find an appropriate model for evaluating uncertainty in enzymatic reference measurements. Methods The CK activity in the sample RELA2012KSA was measured according to IFCC reference method. All the possible sources of uncertainty during the process of measurement were defined and establish the mathematical model of enzymatic reference measurement in the laboratory. The uncertainty of measurement was evaluated for 3 times by GUM and MCM respectively,and then the GUM results were verified by using the adaptive MCM method. Results The sources of uncertainty in the process of CK activity measurement based on the practical conditions of the laboratory were mainly as follows： the corrected reactive rate,the ratio of volume of reaction solution to sample,the reconstitution volume of sample,the optical path of cuvette,the molar absorption coefficient,the deviation of temperature,pH value and wavelength of reaction in measurement. The GUM result of CK measurement in single test was（ 260. 0 ± 12. 2） U / L,and relative expanded uncertainty of the results was 4. 7%. The symmetric coverage interval of 95% probability for 3 tests were（ 247. 829 5,272. 094 7）,（ 246. 938 8,270. 923 6） and（ 246. 495 1,269. 857 5） U/L,respectively. The average value of GUM results of for 3 tests was（ 259. 0 ±7. 0） U/L,and relative expanded uncertainty of this result was 2. 7%. The MCM results of 3 tests were 260. 0,259. 0 and 258. 2 U / L for estimated value of output quantities,and the symmetric coverage intervals of 95% probability were（ 248. 753 2, 271. 535 7）,（ 247. 746 9,270. 418 0） and（ 247. 303 9,269. 330 8） U / L,respectively. The coverage intervals of GUM were verified by MCM,and both the dlow and dhigh values of 3 tests were more than 0. 05 of the numerical tolerance,so the results of GUM were unfavorable that GUM could not be validated by MCM. Conclusion The results of MCM should be more accurate than those of GUM for submitting the report of laboratory. The GUM results may be used to find the different sources of uncertainty after its quality was verified by MCM so as to enhance the efficiency of laboratory quality improvement. The combination of GUM and MCM could be the choice of approach for evaluating the uncertainty in enzymatic reference measurement.
出处
《临床检验杂志》
CAS
CSCD
北大核心
2014年第5期382-389,共8页
Chinese Journal of Clinical Laboratory Science
基金
国家高技术研究发展计划(2011AA02A102
2011AA02A116)
关键词
不确定度
酶学参考测量
GUM不确定度框架
蒙特卡洛法
uncertainty
enzymatic reference measurement
GUM uncertainty framework
Monte Carol method
作者简介
汪静，1972年生，女，副主任技师，硕士，主要从事酶学参考方法的建立及应用研究工作。
通信作者：陈文祥，研究员，E-mail：wxchen@nccl．org．cn。
