摘要目的：探讨如何确定实验室的非衍生化串联质谱法11种氨基酸正常值范围。方法收集南京市妇幼保健院分娩的22430名健康新生儿及14例氨基酸代谢障碍性疾病患儿的11种氨基酸初次筛查数据，其中包括有丙氨酸（Ala）、精氨酸（Arg）、瓜氨酸（Cit）、甘氨酸（Gly）、异亮-亮氨酸（Leu＋Ile）、蛋氨酸（Met）、鸟氨酸（Orn）、苯丙氨酸（Phe）、脯氨酸（Pro）、酪氨酸（Tyr）、缬氨酸（Val），将所得到的新生儿氨基酸数据设定成不同的临界值，应用百分位数法并结合ROC曲线法确定该11种氨基酸的正常值范围。结果频数分布直方图提示除精氨酸呈偏态分布以外，其余10种氨基酸近似正态分布，确定0.2％～99.8％作为该11种氨基酸的最佳百分界值。结论百分位数法结合ROC曲线法可用于确定新生儿氨基酸非衍生化串联质谱法的参考值范围，为其他筛查中心制定其实验室的截断值提供了参考依据。（中华检验医学杂志，2016，39：756-760）

abstractsObjective To determine the reference values of 11 amino acids measured by non-derivatized tandem mass spectrometry ( MS/MS).Methods 22 430 healthy newborns and 14 children with metabolic dysfunction in Nanjing were enrolled in this study.The levels of the 11 amino acids, including Ala, Arg, Cit, Gly, Leu +Ile, Met, Orn, Phe, Pro, Tyr and Val, were measured by non-derivatized tandem mass spectrometry using dry blood spots.After pre-setting up different cutoff values according to the amino acid levels of the newborns, reference value ranges of the 11 amino acids were determined by using the method of percentile combined with ROC curves.Results According to the results of frequency distribution histogram, the levels of the 11 amino acids of newborns belong to approximate normal distribution.By analysis of ROC curves, the cut-off values for amino acids were 0.2%-99.8%.Conclusion It established reference values of 11 amino acids in newborn and provided basis for the other screening center to make the cut-off value.