Comparison of creatinine clearance (CCl) with plasma creatinine (pCr) on entry into the ICU in the (A) known baseline cohort and (B) entire cohort. Dashed lines represent optimum cut-points for diagnosis of acute kidney injury (AKI) according to a change in CCl (CCl < 48.6 ml/min) or change in pCr (pCr > 1.24 mg/dl). (A) The four possible diagnoses (i) No AKI (ΔpCrNo-AKI and ΔCClNo-AKI), (ii) AKI by the clearance criterion only (ΔpCrNo-AKI and ΔCClAKI), (iii) AKI by the pCr criterion only (ΔpCrAKI and ΔCClNo-AKI) or (iv) AKI by both criteria (ΔpCrAKI and ΔCClAKI) are illustrated by squares for ΔpCrAKI and closed circles or squares for ΔCClAKI. (B) Oliguric (urine output < 0.5 ml/kg/h average over 4 h, closed circles), and non-oliguric (open circles) for the entire cohort. No-AKI (CClNo-AKI): without AKI; ΔpCr: relative change in pCr from baseline; ΔCCl: relative change in CCl from Cockcroft-Gault (CG) baseline; AKI (pCrAKI): with AKI.