Receiver operating characteristic (ROC) curves of urine creatinine concentration (Ucrea; mg/dL) for predicting urine protein/creatinine ratio (UPCR) accuracy.

<p>ROC curves of urine creatinine concentration predicted overestimation of daily protein excretion by UPCR in urine samples with specific gravity ≦ 1.005 (panel A: specific gravity category group 1, <i>n</i> = 46; cut-off value result: Ucrea ≦ 38.8 mg/dL), and predicted underestimation in those specific gravity ≧ 1.015 (panel B: specific gravity category groups 3–6, <i>n</i> = 371; cut-off value result: Ucrea ≧ 63.6 mg/dL), in those specific gravity ≧ 1.020 (panel C: specific gravity category groups 4–6, <i>n</i> = 189; cut-off value result: Ucrea ≧ 62.1 mg/dL), and in those specific gravity ≧ 1.025 (panel D; specific gravity category groups 5–6, <i>n</i> = 57; cut-off value result: Ucrea ≧ 61.5 mg/dL), respectively. Abbreviation: AUC, area under curve.