目的:评估受控衰减指数（CAP）对健康体检人群非酒精性脂肪性肝病的定量诊断价值。方法:在健康体检中心开展一项全国多中心研究，2014年4月至12月共纳入173例受检者，均完成身高、体重、血压等人体学指标测量，进行血常规、肝功能、血脂等检测，以及FibroScan和磁共振质子密度脂肪含量 （MRI-PDFF）检查。采用Spearman系数和Pearson系数描述MRI-PDFF与CAP的相关性。应用受试者工作特征曲线及曲线下面积评估CAP的诊断效能，并根据Youden指数确定最佳截断值。结果:入组受检者年龄（45.0±10.5）岁，体质指数（25.8±4.0）kg/mn 2。CAP值和lg转换的MRI-PDFF值呈线性相关（Pearson系数= 0.772， n P<0.001）。CAP区分非脂肪肝（S0）和轻度脂肪肝（S1）的截断值为244 dB/m。n 结论:CAP与MRI-PDFF测得的肝脂肪含量显著相关，并能对肝脂肪变性程度进行分级，可作为常规健康体检中筛查脂肪肝的工具。“,”Objective:To evaluate the quantitative diagnostic value of controlled attenuation parameter (CAP) in health checkup groups with asymptomatic nonalcoholic fatty liver disease.Methods:A multicenter prospective study was conducted among Chinese individuals undergoing regular health checkups; a total of 173 subjects were investigated. Human body indexes such as height, weight, and blood pressure were measured, and complete blood count, liver function, blood lipid, FibroScan, and MRI-PDFF examinations were performed. Correlation between MRI-PDFF and CAP was described using Spearman′s and Pearson′s coefficients. Diagnostic efficacy of the CAP was evaluated using the subject work characteristic curve and the area under this curve, and the optimal cut-off value was determined according to the Youden index.Results:The average age and body mass index of the subjects were 45.0±10.5 years and 25.8±4.0 kg/mn 2, respectively. A linear correlation was found between CAP and lg transformed magnetic resonance imaging-based proton density fat fraction results (Pearson′s coefficient 0.772, n P<0.001). When optimized for ≥90% sensitivity, the CAP cutoff for staging ≥S1 steatosis was 244 dB/m.n Conclusions:The CAP result was significantly correlated with the liver fat fraction measured by MRI-PDFF, and capable of differentiating steatosis grades. CAP can be used as a tool for screening fatty liver in health checkup groups.