Reit C, Gröndahl H G
Scand J Dent Res. 1983 Jun;91(3):213-8. doi: 10.1111/j.1600-0722.1983.tb00804.x.
The presence or absence of periapical radiolucencies, after a predetermined healing period, have been used as a criteria for therapeutic success or failure in endodontic treatment. However, in radiologic diagnosis it has been shown that variations within and between examiners are substantial. In the present study six endodontists evaluated the periapical tissues in radiographs of 119 endodontically treated roots using a five-graded rating scale. An earlier study on the same radiograph material served as reference and "true" states of the periapical tissues were established. True positive and false positive reports on the presence of periapical lesions could then be calculated. For each observer it was noticed that a higher true positive percentage always was coupled with a higher false positive percentage and vice versa. If pairs of true positive and false positive percentages were plotted on a two-dimensional graph they corresponded well to a Receiver Operating Characteristic (ROC) curve. Variations between the observers could be explained by their adoption of different criteria of periapical disease resulting in different positions on the ROC curve. Influence of observer variation on reported frequencies of periapical lesions was greater, the lower the prevalence of the disease. The best opportunities for revealing relative differences in disease prevalences was created when the examiner defined a strict criterion for disease and reported a positive finding only when absolutely certain.
在经过预定的愈合期后，根尖周透射区的有无已被用作牙髓治疗成功或失败的标准。然而，在放射学诊断中，已表明检查者内部和检查者之间的差异很大。在本研究中，六位牙髓病医生使用五级评分量表评估了119颗接受牙髓治疗牙根的根尖周组织的X光片。一项对相同X光片材料的早期研究作为参考，并确定了根尖周组织的“真实”状态。然后可以计算根尖周病变存在的真阳性和假阳性报告。对于每位观察者，都注意到较高的真阳性百分比总是与较高的假阳性百分比相关联，反之亦然。如果将真阳性和假阳性百分比对绘制在二维图上，它们与受试者工作特征（ROC）曲线非常吻合。观察者之间的差异可以通过他们采用不同的根尖周疾病标准来解释，这导致在ROC曲线上的位置不同。疾病患病率越低，观察者差异对报告的根尖周病变频率的影响就越大。当检查者定义严格的疾病标准并仅在绝对确定时报告阳性发现时，就创造了揭示疾病患病率相对差异的最佳机会。
