离子选择电极法与干化学法测定血清钾的方法学比较

COMPARISON OF TWO METHODS AS ION-SELECTIVE ELECTRODES METHOD AND THIN-FILM METHOD TO ANALYZE THE SERUM POTASSIUM

目的分析离子选择电极法与干化学法测定血清钾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,每天随机从临床样本中抽取8份,分别用两种方法进行血清钾的测定,共测定5天,应用SPSS软件对所测数据进行统计。结果以离子选择电极法为对比方法(X)对干化学法(Y)进行评估,两者测定血清钾的回归方程为Y=0.929X+0.344,相关系数r2=0.965,血清钾浓度为2.80mmol/L、4.00mmol/L、6.20mmol/L时,干化学法的相对偏倚分别为4.88%、1.49%、1.63%。结论两种方法测定血清血清钾具有良好的相关性,其相对预期偏倚随血清钾浓度增高而降低。

Objective To compare the result of thin- film method to analyze the serum potassium with that of ion - selective electrodes method, and evaluate its deviation. Methods According to the plan of EPA - 9 which was decided by American Clinical Laboratory Standard Commission （NCCLS） , 8 cases were selected randomly from clinical samples everyday. The serum potassium was determined by the two methods for 5 days, results were registered and analyzed by spss statistic software. Results the relationship between the results of two methods was ： Y = 0. 929X ＋0. 344,r2 =0. 965. Y stand for the result of thin - iilm method, X stand for the result of ion - selective electrodes method. When the serum potassium was 2. 80 mmol/L,4.00 mmol/L,6.20 mmol/L,the deviation of thin -film method analysis was 4. 88% ,1.49% ,1.63%. Conclusion The results of two methods has high correlation, which has no significant difference with each other. When serum potassium increases, the correspondent prospectine deviation decrease.