摘要
目的验证常规方法测定血清尿素、肌酐浓度的正确度，以评价其校准溯源性。方法选择20份经同位素稀释气相色谱质谱法（ID—GC／MS）进行尿素定值的新鲜冰冻患者血清作为标本，用常规方法测定尿素浓度；另选择20份经同位素稀释液相色谱串联质谱法（ID—LC／MS／MS）进行肌酐定值的新鲜冰冻患者血清作为标本，用待评价系统测定肌酐浓度；分别将尿素和肌酐的测定结果与质谱法认定值进行线性回归分析，计算百分偏倚并评估预期偏倚。结果常规方法测定尿素结果与认定值间线性回归方程为Y=0．9890X＋0．0192（R2=0．9990，P〈0．01，n=20）；测定肌酐结果与认定值间线性回归方程为Y=0．9815X-6．4794（R。=0．9989，P〈0．01，n=20）；尿素、肌酐测定结果的平均百分偏倚分别为-0．41％（P〉0．05）和-4．20％（P〈0．05）；通过线性回归方程计算出在3个医学决定水平的预期百分偏倚分别为尿素：-0．46％、-0．83％、-0．96％；肌酐：-15．90％、-5．87％、-2．95％。结论常规方法定尿素结果和参考方法一致，结果可溯源至ID-GC／MS方法；肌酐测定结果与参考方法之间的偏倚符合根据生物学变异导出的“最低性能规范要求”，但是其特异性有改进的余她。
Objective To verify the trueness and assess the traceability of results from a routine chemistry system procedure for measurement of urea and creatinine in serum. Methods Series of fresh frozen patient sera, whose values of urea or creatinine were assigned by isotope dilution gas chromatography mass spectrometry （ID-GC/MS） or isotope dilution liquid chromatography tandem mass spectrometry （ID- LC/MS/MS）, were chosen to be analyzed by a routine chemistry system. The measurement results of urea and creatinine by the routine chemistry system were used for linear regression analysis against the assigned values by the ID-MS method to calculate the percentage deviation and assess the expected bias. Results For urea and creatinine, the linear regression equations between the routine chemistry system and ID-MS methods were Y = 0. 9890X ＋ 0. 0192 （ R2 = 0. 9990） and Y = O. 9815X - 6. 4794 （ R2 = O. 9989 ）, and the average percentage bias were - 0.41% （ P 〉 0. 05 ） and - 4. 20% （ P 〈 O. 05 ） , respectively. The expected percentage bias at three medical decision levels were - 0.46% , - 0. 83% and - 0. 96% for urea and - 15.90% , - 5.87% and - 2. 95% for ereatinine. Conclusions The results of urea analyzed by the routine chemistry system were consistent with the ID-MS method, which suggested that the results of the routine system procedure could be traced to ID-GC/MS method. For creatinine, the bias between the results of routine procedures and the assigned values met the ＂minimum acceptance criteria＂ derived from biologic deviations, which would be better if its specificity improved.
出处
《中华检验医学杂志》
CAS
CSCD
北大核心
2012年第10期912-915,共4页
Chinese Journal of Laboratory Medicine
基金
国家高技术研究发展计划（“863”计划）资助项目（2011AA02A102,2011AA02A116）
国家技术支撑计划资助项目（2012BA137B01）
