Table 3.

Diagnostic performance according to sample length.

Duration (s)	Accuracy, mean percentage	Sensitivity, mean percentage	Specificity, mean percentage	Positive-predictive value, mean percentage	Negative-predictive value, mean percentage	AUCa (95% CI)
30	96.89	98.96	94.34	95.55	98.67	0.993 (0.992-0.993)
25	96.53	99.08	93.40	94.85	98.80	0.991 (0.990-0.991)
20	96.44	98.89	93.43	94.87	98.56	0.992 (0.992-0.992)
15	96.01	98.47	92.99	94.52	98.02	0.990 (0.990-0.990)
10	94.72	97.46	91.35	93.26	96.69	0.985 (0.985-0.986)
5	90.55	94.68	85.49	88.91	92.90	0.966 (0.965-0.966)

^aAUC: area under the receiver operating characteristic curve.