Table 8: ROC area for VEGF-A and sorbitol tests (solo or combined) for diagnosing any type of DR by differentiating it from DNR.

	ROC area	p
Positive VEGF-A test (at optimum cut-off value of >=124.7 ng/ml)	0.766	<0.001
Positive Sorbitol test (at optimum cut-off value of >= 0.3112 mg/L)	0.777	<0.001
Parallel tests combination	0.768	<0.001
Serial tests combination	0.774	<0.001