[ROC: a method for comparing the diagnostic performance of imaging procedures].

ROC analysis permits an evaluation of the diagnostic performance of imaging systems by incorporating the individual decision threshold of the diagnostician that determines the relation between sensitivity and specificity of a tested system. It therefore facilitates the comparison between different imaging systems and observers. A thorough knowledge and sophistication of this methodology is of special importance in the comparison of digital and conventional projection radiography because the images in question may have a very similar character. The method is explained and special points of interest (standard of "truth", size of sample, lesion conspicuity and localisation, viewing time and determination of significance) are emphasised.