Liver biopsy: the best standard...when everything else fails.

摘要

We fully agree with the basic statement by Mehta et al. that the conventional method used so far, for validation of surrogate markers has an intrinsic limitation, because the reference standard, in this case liver biopsy, is imperfect in regard to the prediction of the disease. In chronic hepatitis C core fragments of 40 mm have a 25% rate of misclassification of META-VIR stages [2]. Ironically, striving for the highest AUR-OC will only result in a test having the same high rate of misclassification vs. the presence of the disease. Depending on the prevalence of the disease and the sensitivity and specificity of liver biopsy, a surrogate with a lower AUROC might provide a better prediction of the disease than one with a higher AUROC. Another rational consequence is that studies observing 100% AUROC for any biomarker validated with biopsy are either underpowered or faked.