改良洛杉矶院前卒中筛查量表敏感性及特异性研究

目的 评价改良洛杉矶院前卒中筛查量表(MLAPSS)对卒中患者诊断的敏感性及特异性. 方法 深圳市盐田区盐港医院、深圳市宝安区松岗人民医院、湖南省常德市第一人民医院及湖南省常德市第四人民医院四家医院院前及急诊内科医生采用MLAPSS对可疑脑卒中患者进行筛查,评价MLAPSS对脑卒中诊断的灵敏度、特异度、阳性预测值、阴性预测值、似然比和Youden指数. 结果 符合初筛标准患者2016例,男性1120例,女性896例;年龄20～95岁(平均年龄42岁);符合MLAPSS筛查标准患者531例,男性291例,女性240例;年龄33～93岁(平均年龄54岁).最后诊断脑卒中157例,其中缺血性脑卒中82例、脑出血58例、短暂性脑缺血发作(TIA)17例.MLAPSS筛查组灵敏度、特异度及Youden指数分别为89%(95%CI;85,95)、95%(95%CI;93,97)及0.85(95%CI 0.76,0.94);阳性预测值和阴性预测值分别为89%(95%CI;82,95)、96%(95%CI;90,100).初筛组灵敏度、特异度及Youden指数分别为88%(95%CI;82,94)、99%(95%CI;97,100)及0.87(95%CI;0.81,0.93);阳性预测值和阴性预测值分别为89%(95%CI;83,95)、99%(95%CI;97,100).MLAPSS筛查组阳性似然比和阴性似然比分别为18、0.11;初筛组阳性似然比和阴性似然比分别为88、0.12.MLAPSS筛查组漏诊率为10%,误诊率为5%;初筛组漏诊率为12%,误诊率为1%.完成MLAPSS筛查时间为3 min 31 s～5 min 15 s(平均时间4 min 17 s). 结论 结果 初步显示MLAPSS对卒中筛查敏感性提高,能有效减少漏诊,维持较高的特异性及预测值,且操作简便费时少,具有较强的实用价值.

Sensitivity and specificity of modified Los Angeles prehospital stroke green

Objective To evaluate the sensitivity and specificity of modified Los Angeles prehospital stroke screen (MLAPSS) in the diagnosis of acute stroke. Methods Prehospital personnel and physicians in the Emergency Department of 3 hospitals were trained for appropriate use of MLAPSS. The sensitivity, specificity, positive predictive value, negative predictive value, likelihood ratios, and Youden's index of MLAPSS for diagnosis of acute stroke were evaluated in patients with ischemic stroke, transient ischemic attack and intracerebral hemorrhage. Results Of a total of 2016 patients, 531 met the screening criteria of MLAPSS, among whom 157 had a final diagnosis of acute symptomatic cerebrovascular disease, including 82 with ischemic stroke, 17 with transient ischemic attack and 58 with intracerebral hemorrhages. The sensitivity, specificity and Youden index of MLAPSS for acute stroke diagnosis were 89% (95%CI: 85, 95), 95% (95%CI: 93, 97) and 0.85 (95%CI: 0.76, 0.94), with positive and negative predicted values of 89% (95%CI: 82, 95) and 96% (95%CI: 90, 100), and positive and negative likelihood ratios of 18 and 0.11, respectively. In the 531 patients, the missed diagnosis rate was 10% and the misdiagnosis rate was 5%. The average time to complete MLAPSS screening was 4 mitt 17 s. Conclusions MLAPSS has a relatively high sensitivity in the diagnosis of acute stroke with reduced misdiagnosis rate and high levels of specificity and predictive value. With easy operation, MLAPSS allows efficient screening of patients with acute stroke.