The Usefulness of Serum Sorbitol and Vascular Endothelial Growth Factor A in Predicting Diabetic Retinopathy as Compared to Optical Coherence Tomography

Table 9: Validity parameters for VEGF-A and sorbitol tests (solo or combined) for diagnosing any type of DR and differentiating it from DNR

Positive if ≥ cut-off value	Sensitivity	Specificity	Accuracy	PPV at pretest probability		NPV at pretest probability = 10%
Positive if ≥ cut-off value	Sensitivity	Specificity	Accuracy	50%	90%	NPV at pretest probability = 10%
Positive VEGF-A test (at optimum cut-off value of >=124.7 ng/ml)	73.1	80.0	74.4	78.5	97.1	96.4
Positive sorbitol test (at optimum cut-off value of >= 0.3112 mg/L)	75.4	80.0	76.2	79.0	97.1	96.7
Parallel tests combination	90.3	63.3	85.4	71.1	95.7	98.3
Serial tests combination	58.2	96.7	65.2	94.6	99.4	95.4