Table 3.

Performance of the CNN and CNN-LSTM models for the five-level drowsiness classifications for different combinations of input signals.

Model Name	Input Signal	Accuracy (%)	Sensitivity (%)	Specificity (%)	Precision (%)
CNN	HRV	51	50	48	51
	HRV-PSD	52	53	54	52
	RR	55	59	56	52
	HRV + HRV-PSD	57	56	56	52
	HRV + RR	59	60	61	56
	HRV-PSD + RR	57	59	52	56
	All inputs	64	62	67	62
CNN-LSTM	HRV	54	50	51	50
	HRV-PSD	58	56	63	54
	RR	60	60	65	63
	HRV + HRV-PSD	61	60	61	59
	HRV + RR	63	62	62	63
	HRV-PSD + RR	60	55	62	53
	All inputs	67	67	70	66

HRV: heart rate variability, HRV-PSD: power spectral density of HRV, RR: respiration rate.