全国新生儿遗传代谢病串联质谱筛查氨基酸检测项目的西格玛水平分析

Analysis of sigma levels for the amino acid detection in the national newborn screening for inherited metabolic diseases with tandem mass spectrometry

目的对全国新生儿遗传代谢病串联质谱筛查氨基酸项目的检测性能进行西格玛水平的分析,以发现检测中存在的问题,提高临床实验室质量水平。方法利用国家卫生健康委临床检验中心开发的软件平台收集2019年4月全国临床实验室新生儿遗传代谢病串联质谱筛查氨基酸检测项目的室间质量评价(EQA)和室内质量控制(IQC)数据,检测项目包括苯丙氨酸、瓜氨酸、甲硫氨酸、酪氨酸、亮氨酸和缬氨酸。用EQA数据估计偏倚(bias),IQC数据估计不精密度水平,并利用公式σ=(TEa-bias)/CV计算各个氨基酸检测项目的西格玛度量值。结果回报苯丙氨酸、瓜氨酸、甲硫氨酸、酪氨酸、亮氨酸和缬氨酸EQA和IQC数据的实验室数目分别为156、154、156、156、156和157家。6种氨基酸检测项目的σ水平分布相似。大部分实验室的σ水平在0~3之间,比例均大于50%,其中缬氨酸项目的比例最高,为61.78%。3≤σ<6的实验室约为30%~40%。对于所有氨基酸检测项目来说,σ≥6的实验室比例均小于10%,其中比例最高的为苯丙氨酸,达7.69%。结论目前我国新生儿遗传代谢病串联质谱筛查氨基酸检测项目的整体σ水平较低。实验室还需进一步改善检测性能,以获得更高的σ水平,提高检验结果的质量。

Objective To analyze the sigma levels of the amino acid detection in the national newborn screening of inherited metabolic diseases with tandem mass spectrometry,so as to find out the problems in the process of detection and improve the quality level of clinical laboratories in China.Methods The data of external quality assessment(EQA)and internal quality control(IQC)for the amino acid detection in the national newborn screening of inherited metabolic diseases with tandem mass spectrometry from clinical laboratories in April 2019,including phenylalanine,citrulline,methionine,tyrosine,leucine and valine,were collected via the software platform developed by the National Center for Clinical Laboratories of the National Health Commission.Bias and imprecision were estimated by EQA and IQC data,respectively.The sigma metric of each amino acid detection was calculated using the formulaσ=(TEa-bias)/CV.Results The numbers of clinical laboratories reporting the EQA and IQC data of phenylalanine,citrulline,methionine,tyrosine,leucine and valine were 156,154,156,156,156 and 157,respectively.The distribution ofσlevels for 6 amino acid detection items was similar.Theσlevels of most laboratories were between 0 and 3,and the proportions were more than 50%.Among them,the proportion of the valine item(61.78%)was the highest.The proportions of clinical laboratories withσlevels between 3 and 6 were about 30%to 40%.For all amino acid detection items,the proportions of laboratories withσ≥6 were less than 10%,and the proportion of the phenylalanine item(7.69%)was the highest.Conclusion At present,the overallσlevels of amino acid detection items in national newborn screening of inherited metabolic diseases with tandem mass spectrometry are low.Clinical laboratories need to further improve the detection performance in order to obtain a higherσlevel and raise the quality of detection results.