The ROC curve technique and its application in X-ray diagnostics

The method of ROC (receiver operating characteristic) curves is applied in characterizing radiographic imaging systems so as to include the viewer. It is explained in detail and compared with similar observation techniques, such as the method of perceptibility curves. Investigations have shown that the ROC method lends itself well to differentiation among various systems because of its simultaneous assessment of the image parameters of contrast, resolution and noise. As is shown by the example mammography, minor differences in images can be plotted as curves and thus objectified. Assessment of the ROC method proves its value to depend on the correct choice of the test object. If this is taken into account, the ROC method can certainly be a valuable addition to the existing line of techniques available to measure image quality parameters in radiography. (orig.)