Interpretation of Receiver Operating Characteristics(ROC).
- Author:
Jae Duk KIM
1
Author Information
1. Department of Oral and Maxillofacial Radiology, School of Dentistry, Chosun University, Korea. jdakim@mail.chosun.ac.kr
- Publication Type:Original Article
- Keywords:
interpretation of film images;
ROC curve;
diagnostic accuracy
- MeSH:
Diagnosis;
ROC Curve;
Tooth
- From:Korean Journal of Oral and Maxillofacial Radiology
2000;30(3):155-158
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
The purpose of this paper is to explain the making procedure and the usage of receiver operating characteristic curve(ROC) for interpretation of radiographic images. The conventional radiograms obtained after the creation of the lesions in the acrylic plates and were enhanced in color. The observer were informed of which tooth to examine, the 'a priori' probability of a lesion present and the approximate diameter of the lesions. The two groups of films were interpreted separately by the same observer using the same rating scale. The following rating scale was used: A; definitely no lesion, B; probably no lesion, C; not sure, D; probably a lesion, and E; definitely a lesion. In analysis, for each observer the diagnostic results in terms of true positive(TP) and false positive(FP) decisions were plotted on a graph. The lowest point on the graph represents the TP and FP when only decisions designated as E according to the rating scale are included. The next point shows the TP and FP values when diagnoses designated as D are added and so forth. By connecting such plot points, a receiver operating characteristic curves(ROC) is obtained. The area under the curve represents the diagnostic accuracy resulting from a diagnostic performance at pure chance level and a value of 1.0 at perfect performance. This method has been known as an useful method to detect the minute difference for each radiographic technic, each observer and for the different lesion depths.
