Rattenbury J M, Townsend J C
Department of Chemical Pathology, Children's Hospital, Sheffield, UK.
Clin Chem. 1990 Feb;36(2):217-24.
Ten different samples of lyophilized plasma and two of liquid urine were distributed during two years to 26 laboratories performing quantitative amino acid analyses in a scheme designed to provide external quality assessment. After each distribution, statistical summaries and performance scores based on delta standard deviations and percentage biases from the all-laboratory trimmed means were returned to participants, who also received annual performance summaries based on their accumulated results. Coefficients of variation calculated from returns across all the samples ranged from 13% for glycine to 65% for methionine. Automated ion-exchange amino acid analyzers with ninhydrin detection appeared to perform better than other methods, although there was no clearly superior method and no model of analyzer clearly outperformed the others. These exercises demonstrate that there is room for improvement in the performance of quantitative amino acid analyses and that individual expertise may be more important in maintaining good performance than the choice of method or analyzer.
在两年时间里，向26个进行定量氨基酸分析的实验室分发了10份不同的冻干血浆样本和2份液态尿液样本，该计划旨在提供外部质量评估。每次分发后，根据所有实验室剔除均值的标准差增量和百分比偏差得出的统计摘要和性能分数会返还给参与者，他们还会收到基于其累积结果的年度性能总结。根据所有样本的反馈计算出的变异系数范围为：甘氨酸13%，蛋氨酸65%。带有茚三酮检测的自动离子交换氨基酸分析仪似乎比其他方法表现更好，尽管没有明显更优的方法，也没有哪种分析仪型号明显优于其他型号。这些活动表明，定量氨基酸分析的性能仍有改进空间，而且在保持良好性能方面，个人专业技能可能比方法或分析仪的选择更为重要。
