Table 6.

Sensitivity and specificity at different cutoff values in U-NGAL receiver operating characteristic curve analysis predicting DGF and prolonged DGF^a

U-NGAL cutoff level, ng/mL	DGF				Prolonged DGF
	Sensitivity	Specificity	PPV	NPV	Sensitivity	Specificity	PPV	NPV
4	77.3%	28.4%	0.42	0.65	82.6%	27.6%	0.16	0.91
9	60.6%	54.9%	0.47	0.68	47.8%	49.7%	0.14	0.85
18	37.9%	77.5%	0.53	0.65	47.8%	74.5%	0.24	0.90
20	34.8%	79.4%	0.53	0.65	43.5%	76.6%	0.24	0.89

^aNPV, negative predictive value; PPV, positive predictive value. The selected cutoff values are the lowest quartile (4 ng/mL), the median (9 ng/mL), the mean (18 ng/mL) and the highest quartile (20 ng/mL).