Gao Guo-fu, Zhao Fang-hui, Wu Yan-ping, Rong Shou-de, Zhang Wen-hua, Pan Qin-jing, Li Ling, Qiao You-lin
Department of Epidemiology, Cancer Institute/Hospital, CAMS, PUMC, Beijing 100021, China.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao. 2002 Dec;24(6):573-6.
To analyze the effect of gold standard, blind comparison and different cut-points choosing on screening techniques assessment, and to promote the application of evidence-based medicine theory in screening study.
A screening study for cervical cancer in rural China in 1999, where 1997 women had been tested for pathology as gold standard and simulating situations without gold standard, blind comparison and under different cut-points. Indices such as detectable rate, sensitivity and specificity were calculated for each technique. Receiver operating characteristics (ROC) curves were drawn and areas under ROC curves between screening techniques were tested.
Without gold standard, diagnostic techniques could not be evaluated correctly, and without the blind comparison, the sensitivity and specificity of the tests would be subjectively increased. Furthermore, use of different cut-points led to different sensitivities and specificities of test.
Gold standard, blind comparison and perfect cut-points can improve the quality of screening test and drawing ROC curves is an effective way to confirm cut-points and evaluate diagnostic techniques. It is necessary to enforce the application of evidence-based medicine theory in scientific research.
分析金标准、盲法比较及不同切点选择对筛查技术评估的影响，促进循证医学理论在筛查研究中的应用。
1999年在中国农村开展的一项宫颈癌筛查研究，以1997名妇女的病理检查结果作为金标准，模拟无金标准、盲法比较及不同切点的情况。计算每种技术的检出率、灵敏度和特异度等指标。绘制受试者工作特征（ROC）曲线，并检验筛查技术之间ROC曲线下面积。
无金标准时，诊断技术无法得到正确评估；无盲法比较时，检测的灵敏度和特异度会被主观提高。此外，使用不同切点会导致检测的灵敏度和特异度不同。
金标准、盲法比较和合适的切点可提高筛查试验质量，绘制ROC曲线是确定切点和评估诊断技术的有效方法。在科研中加强循证医学理论的应用很有必要。
