Rose D N, Schechter C B, Adler J J
Department of Community Medicine, Mount Sinai School of Medicine, New York, New York, USA.
J Gen Intern Med. 1995 Nov;10(11):635-42. doi: 10.1007/BF02602749.
To reinterpret epidemiologic information about the tuberculin test (purified protein derivative) in terms of modern approaches to test characteristics; to clarify why different cutpoints of induration should be used to define a positive test in different populations; and to calculate test characteristics of the intermediate-strength tuberculin skin test, the probability of Mycobacterium tuberculosis infection at various induration sizes, the area under the receiver operating characteristic (ROC) curve, and optimal cutpoints for positivity.
Standard epidemiologic assumptions were used to distinguish M. tuberculosis-infected from -uninfected persons; also used were data from the U.S. Navy recruit and World Health Organization tuberculosis surveys; and Bayesian analysis.
In the general U.S. population, the test's sensitivity is 0.59 to 1.0, the specificity is 0.95 to 1.0, and the positive predictive value is 0.44 to 1.0, depending on the cutpoint. Among tuberculosis patients, the sensitivity is nearly the same as in the general population; the positive predictive value is 1.0. The area under the ROC curve is 0.997. The probability of M. tuberculosis infection at each induration size varies widely, depending on the prevalence. The optimal cutpoint varies from 2 mm to 16 mm and is dependent on prevalence and the purpose for testing.
The operating characteristics of the tuberculin test are superior to those of nearly all commonly used screening and diagnostic tests. The tuberculin test has an excellent ability to distinguish M. tuberculosis-infected from -uninfected persons. Interpretation requires consideration of prevalence and the purpose for testing. These findings support the recommendation to use different cutpoints for various populations. Even more accurate information can be gotten by interpreting induration size as indicating a probability of M. tuberculosis infection.
运用现代检测特征方法重新解读结核菌素试验（纯蛋白衍生物）的流行病学信息；阐明为何在不同人群中应使用不同的硬结切点来定义阳性试验；计算中等强度结核菌素皮肤试验的检测特征、不同硬结大小下结核分枝杆菌感染的概率、受试者操作特征（ROC）曲线下面积以及阳性的最佳切点。
采用标准流行病学假设区分结核分枝杆菌感染与未感染人群；还使用了美国海军新兵和世界卫生组织结核病调查的数据；以及贝叶斯分析。
在美国普通人群中，根据切点不同，该试验的敏感性为0.59至1.0，特异性为0.95至1.0，阳性预测值为0.44至1.0。在结核病患者中，敏感性与普通人群相近；阳性预测值为1.0。ROC曲线下面积为0.997。不同硬结大小下结核分枝杆菌感染的概率因患病率而异。最佳切点从2毫米到16毫米不等，取决于患病率和检测目的。
结核菌素试验的操作特征优于几乎所有常用的筛查和诊断试验。结核菌素试验具有出色的区分结核分枝杆菌感染与未感染人群的能力。解读时需要考虑患病率和检测目的。这些发现支持针对不同人群使用不同切点的建议。将硬结大小解读为结核分枝杆菌感染概率能获得更准确的信息。
