Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
Department of Urology, Yale University School of Medicine, New Haven, CT 06520, USA.
Medicina (Kaunas). 2021 May 16;57(5):503. doi: 10.3390/medicina57050503.
Sensitivity, which denotes the proportion of subjects correctly given a positive assignment out of all subjects who are actually positive for the outcome, indicates how well a test can classify subjects who truly have the outcome of interest. Specificity, which denotes the proportion of subjects correctly given a negative assignment out of all subjects who are actually negative for the outcome, indicates how well a test can classify subjects who truly do not have the outcome of interest. Positive predictive value reflects the proportion of subjects with a positive test result who truly have the outcome of interest. Negative predictive value reflects the proportion of subjects with a negative test result who truly do not have the outcome of interest. Sensitivity and specificity are inversely related, wherein one increases as the other decreases, but are generally considered stable for a given test, whereas positive and negative predictive values do inherently vary with pre-test probability (e.g., changes in population disease prevalence). This article will further detail the concepts of sensitivity, specificity, and predictive values using a recent real-world example from the medical literature.
敏感性表示所有实际阳性结果的受试者中正确给予阳性分配的比例，它表明了一项测试在对真正具有研究兴趣的结果的受试者进行分类的能力。特异性表示所有实际阴性结果的受试者中正确给予阴性分配的比例，它表明了一项测试在对真正不具有研究兴趣的结果的受试者进行分类的能力。阳性预测值反映了具有阳性测试结果的受试者中真正具有研究兴趣的结果的比例。阴性预测值反映了具有阴性测试结果的受试者中真正不具有研究兴趣的结果的比例。敏感性和特异性呈反比关系，其中一个增加，另一个就会减少，但对于给定的测试通常被认为是稳定的，而阳性和阴性预测值确实会随预测试概率（例如，人群疾病流行率的变化）而变化。本文将使用来自医学文献的最近的真实示例进一步详细说明敏感性、特异性和预测值的概念。
