FIG 5.

ROC curves for qualitative and quantitative variables show that the best discriminating values for differentiating CS from SC are the following: Mandibular condyle for lesion center, Presence for destruction of the mandibular condyle, Absence for destruction of the articular eminence/glenoid fossa, Absence for sclerosis of the articular eminence/glenoid fossa, Presence for infiltration into the tendon of lateral pterygoid muscle, Stippled pattern of calcification, Presence for periosteal reaction, Presence for internal enhancement, and 30.5 mm for lesion size. Of the 9 variables, except for pattern of calcification and mean lesion size, the remaining 7 variables were dichotomous qualitative variables with discriminating values determined at 1 of the 2 characteristics. On the other hand, mean lesion size was a quantitative variable, and the discriminating value was determined at the point of 30.5 mm, which revealed the maximum Youden index among multiple points. Last, the pattern of calcification, the 5 patterns, namely absence, stippled, flocculent, ring-and-arc, and popcorn, were considered as a dimensional continuum in ascending order and converted into an ordinal quantitative variable. The ROC curve was then constructed, and the discriminating value was derived at the point of stippled calcification, which indicates that CS showed a higher prevalence in absence or stippled calcification, and SC, in the other calcification patterns.