Table 3.

Performance of AI in comparison to Ground Truth for internal and external validation sets

Internal validation set
	Any DR detection		Referable DR detection		Sight threatening DR detection
Sensitivity	99.71%	99.27%-99.92%	98.98%	98.30%-99.44%	97.55%	96.32%-98.46%
Specificity	98.50%	94.71%-99.82%	94.84%	90.08%-97.75%	56.31%	52.35%-60.21%
AUC	0.991	0.985-0.995	0.969	0.959-0.977	0.77	0.747-0.790
PPV	99.86%	99.44%-99.96%	99.42%	98.86%-99.70%	76.00%	74.34%-77.58%
NPV	97.06%	92.53%-98.87%	91.30%	86.16%-94.65%	94.20%	91.43%-96.10%
k	0.975	0.956-0.995	0.922	0.890-0.954	0.572	0.532-0.612
External validation set
	Any DR detection		Referable DR detection		Sight threatening DR detection
Sensitivity	90.37%	87.84%-92.52%	94.68%	92.12%-96.60%	91.67%	83.58%-96.58%
Specificity	91.03%	88.31%-93.29%	97.40%	96.01%-98.40%	92.92%	91.26%-94.36%
AUC	0.907	0.889-0.923	0.96	0.948-0.971	0.923	0.906-0.937
PPV	92.34%	90.22%-94.04%	95.34%	92.99%-96.93%	49.36%	43.84%-54.90%
NPV	88.75%	86.17%-90.90%	97.02%	95.62%-97.98%	99.33%	98.65%-99.67%
k	0.812	0.779-8.845	0.922	0.899-0.945	0.606	0.531-0.680

Any DR=Stage 1, 2, 3, 4; Referable DR=Stage 2, 3, 4; Sight threatening DR=Stage 3 and 4