Fig. 1.

ROC characteristics for prediction of AKI in post-cardiac surgery patients (a) by the AKI peptide marker panel and (b) by the single markers NGAL and KIM-1. Whereas for the AKI peptide marker panel the sensitivity and specificity was determined at the previously established cut-off, these values were determined for NGAL and KIM-1 at the optimal cut-off according to the Youden index. AKI acute kidney injury, AUC area under the ROC curve, KIM-1 kidney injury molecule-1, NGAL neutrophil gelatinase-associated lipocalin, ROC receiver operating characteristic