In sensitivity analyses, predictive value for other WRF definitions/cut-offs showed similar patterns (Tables S3 and S4). Baseline plasma NGAL was independently predictive of WRF in a multivariable model (Table 3), while serum creatinine was not. NGAL contributed significantly to improving WRF prediction (AUC 0.648 vs. 0.635 for model with vs. without NGAL, p = 0.002). In sensitivity analyses, multivariable models for other WRF cut-offs consistently included NGAL, which significantly improved model discrimination in all models (p < 0.05), but not creatinine. However, these small improvements are likely not clinically relevant.