Comparison of adjustment methods for stratified two-sample tests in the context of ROC analysis.

We compare several nonparametric and parametric weighting methods for the adjustment of the effect of strata. In particular, we focus on the adjustment methods in the context of receiver-operating characteristic (ROC) analysis. Nonparametrically, rank-based van Elteren's test and inverse-variance (IV) weighting using the area under the ROC curve (AUC) are examined. Parametrically, the stratified t-test and IV AUC weighted method are applied based on a binormal monotone transformation model. Stratum-specific, pooled, and adjusted estimates are obtained. The pooled and adjusted AUCs are estimated. We illustrate and compare these weighting methods on a multi-center diagnostic trial and through extensive Monte-Carlo simulations.