Fig. 1

a Receiver operating characteristics (ROC) curves for prediction of acute kidney injury (AKI) (stage I or F) with Injury Severity Score (ISS) (AUC = 0.79 (0.75–0.83)), blood lactate (AUC = 0.77 (0.73–0.81)), Creatine kinase (CK) peak (AUC = 0.73 (0.69–0.78)), minimum prehospital mean arterial pressure (MAP) (AUC = 0.70 (0.65–0.75)) and maximum prehospital heart rate (HR) (AUC = 0.66 (0.61–0.71)). The multivariate model includes the following variables: presence of hemorrhagic shock, blood lactate, minimum prehospital MAP, maximum prehospital heart rate, ISS and secondary transfer to a trauma center (Table 4). The AUC-ROC of the multivariate model is 0.85 (0.82–0.88). b ROC curves for prediction of AKI (stage R, I or F) with ISS (AUC = 0.76 (0.73–0.78)), blood lactate (AUC = 0.70 (0.67–0.73)), CK peak (AUC = 0.68 (0.65–0.71)), minimum prehospital MAP (AUC = 0.68 (0.65–0.71)). The multivariate model includes the following variables: presence of hemorrhagic shock, blood lactate, minimum prehospital MAP, ISS, secondary transfer to a trauma center and presence of severe renal trauma (Additional file 3). The AUC-ROC of the multivariate model is 0.80 (0.78–0.83)