用ROC曲线确定cTnI诊断AMI的临界值

目的：确定肌钙蛋白I（cTnI）定量结果应用于急性心肌梗死（AMI）诊断的临界值,并重新评价其临床意义。方法：用酶联荧光分析法测定本院急诊病人198例,其中符合AMI的诊断标准患者标本96例,健康对照组102例。依据测定结果应用统计软件计算敏感度、特异度、阳性似然比和ROC曲线下的面积并进行分析,对AMI诊断的临界值进行评价。结果：根据统计分析,cTnI用于AMI的最佳诊断临界值为0.12μg/L（敏感度83.33%、特异性94.12%、阳性似然比14.16;ROC曲线下的面积为0.816）。结论：cTnI以0.12μg/L作为诊断AMI的临界值较为合适,可提高其临床诊断的效率。

Determination the Cut-off Value of cTnl by ROC( Receiver Operating Curve)in the Diagnosis of AMI

Objective To determine the cut-off value of cTnI by ROC(receiver operating curve) in the diagnosis of AMI.Method Blood samples of 96 cases patients with AMI were collected,and so were those of 102 normal persons served as control group.All these blood samples were measured for cTnI content with enzyme-linked fluorescent assay(ELFA),and then ROC curve was drawn and the cut-off value was determined with statistical software.Results The most appropriate cTn I cut-off value in the diagnosis of AMI was 0.12μg/L(with sensitivity 83.33%,specificity 94.12% and likelihood ratio 14.16).Conclusion Using 0.12μg/L as the cut-off value in the diagnosis of AMI would improve the efficiency of the diagnosis.