Accuracy of cystatin C in prediction of acute kidney injury in children; serum or urine levels: which one works better? A systematic review and meta-analysis

Table 5 Diagnostic performance characteristics of cystatin C in detection of acute kidney injury

Characteristics	TP	FP	FN	TN	P _{for publication bias}	Model	P _{for heterogeneity} (I²)	Effect size (95% CI)
a) Serum level	543	445	206	1102
Overall area under the curve					0.08	REM	<0.001 (80.0)	0.83 (0.80-0.86)
0.4-1 mg/L	314	361	53	386
Sensitivity					0.29	REM	<0.001 (77.6)	0.85 (0.78-0.90)
Specificity					0.29	REM	<0.001 (94.6)	0.61 (0.48-0.73)
Positive likelihood ratio					0.29	REM	<0.001 (92.8)	2.18 (1.66-2.88)
Negative likelihood ratio					0.29	REM	0.01 (60.3)	0.24 (0.18-0.34)
1.01-2.5 mg/L	229	84	153	716
Sensitivity					0.01	REM	<0.001 (87.1)	0.65 (0.49-0.77)
Specificity					0.01	REM	<0.001 (87.8)	0.88 (0.79-0.94)
Positive likelihood ratio					0.01	REM	<0.001 (64.5)	5.56 (3.62-8.53)
Negative likelihood ratio					0.01	REM	<0.001 (85.5)	0.40 (0.28-0.56)
b) Urine level	93	37	128	295
Overall area under the curve					0.07	REM	<0.001 (83.3)	0.85 (0.81-0.88)
Sensitivity					0.07	REM	<0.001 (83.3)	0.47 (0.29-0.66)
Specificity					0.07	REM	0.09 (54.3)	0.89 (0.83-0.93)
Positive likelihood ratio					0.07	FEM	0.24 (0.0)	4.24 (2.93-6.13)
Negative likelihood ratio					0.07	REM	0.04 (63.2)	0.60 (0.43-0.83)

AKI acute kidney injury, CI confidence interval, FEM fixed effect model, REM random effect model, TP true positive, TN true negative, FP false positive, FN false negative

ISSN: 1471-2369