Dear group I read a article about 'covariate-speific ROC curve':(below article, figure 5) http://www.stata-journal.com/sjpdf.html?articlenum=st0155 I think author did not stratify the age group(below 30, 30~40, 40~50), but how could authors specificity the AUC function according to certain Age(months) level? Can I draw age-specific-ROC curves without stratification of Age group? Thank you very much. Best regards. [[alternative HTML version deleted]]