重氮法与钒酸盐氧化法测定总胆红素的方法学比较

目的分析重氮法与钒酸盐氧化法测定血清总胆红素结果的相关性，并对两法进行偏倚评估，建立仪器间的校正方法。方法依据美国国家临床实验室标准委员会（NCCLS）EP9．A文件方案，每天随机抽取8份血清标本，分别用重氮法与钒酸盐氧化法进行总胆红素测定，共测定5d。对检验结果进行离散点检查，计算线性方程和相关系数并进行偏倚估计。结果以重氮法（X）为参比方法，对钒酸盐氧化法（Y）进行评估，两者测定总胆红素的回归方程为Y=1．1588X-2．4616，相关系数R2=0．998。总胆红素浓度为34．2、171μmol／L、342μmol／L时，钒酸盐氧化法的相对偏倚分别为8．72％、14．42％、15．12％。结论两种方法测定血清总胆红素具有良好的相关性，其比例误差是0．1588，恒定误差是．2．4616μmol／L。其相对预期偏倚随总胆红素浓度增高而增高。

Comparison of two methods,Diazonium method and vanadate oxidation method, for assay of the total bilirubin

Objective To compare the result with diazonium method and vanadate oxidation method for assay of the serum total bilirubin , then evaluate its deviation. Methods According to the standard of EP9-A which was decided by American Clinical Laboratory Standard Commission （ NCCLS）, 8 cases were selected randomly ever-day. The total bilirubin was analyzed by the two methods, diazonium method and vanadate oxidation method for 5 days, the data was recorded and the separate spots were tested. The linear equation and the coefficient of correlation were calculated as well as the bias between two methods was estimated. Results The relationship between the results of the two methods was： Y = 1. 1588X -2. 4616,, R2 =0. 998 ,in which Y standed for the result of vanadate oxidalion method, and X standed for the result of diazonium method. When the total bilirubin were 34. 2μmol/L, 171 μmol/L,342μmol/L, the deviation of vanadate oxidation method analysis were 8.72%, 14. 42%, 15.12% respectively. Conclusion The results of two methods have high correlation. The proportional error is 0. 158 8, and the constant error is - 2. 4616μmol/L. When total bilirubin increases, the correspondent prospective deviation also increase.