Standardization of ROC Curve Areas for Diagnostic Evaluation of Liver Fibrosis Markers Based on Prevalences of Fibrosis Stages

The area under the ROC curve (AUC) is widely used as an estimate of the diagnostic value for fibrosis markers. Whether there is variability in the AUC related to the prevalence of fibrosis stages defining advanced and nonadvanced fibrosis is unknown. The aim of this study was to assess the relationships between the AUC and the prevalence of each fibrosis stage and to elaborate simple methods of standardization. The AUCs of FibroTest (FT) for the diagnosis of advanced fibrosis were estimated in patients with chronic hepatitis C using an integrated database including 1312 patients with FT and biopsy, and in an overview of 18 diagnostic studies. In the integrated database considering stage prevalence, the FT AUC for advanced fibrosis varied (P