Table 14.

Multi-class classification of LF from all datasets for CO (Class 0), PD Stage 2 (Class 2), PD Stage 2.5 (Class 2.5), and PD Stage 3 (Class 3) using several CNN classifiers (AlexNet, ResNet-50, ResNet-101, and GoogLeNet) with 10-fold cross-validation.

Time Window	Frequency Range	Disease Severity (Class)	AlexNet				ResNet-50				ResNet-101				GoogLeNet
			Sen (%)	Spec (%)	Acc (%)	AUC	Sen (%)	Spec (%)	Acc (%)	AUC	Sen (%)	Spec (%)	Acc (%)	AUC	Sen (%)	Spec (%)	Acc (%)	AUC
10 s	0.83–1.95 Hz	Class 0	92.15	94.56	93.82	0.9335	93.86	96.88	95.95	0.9537	94.27 *	97.68 *	96.63 *	0.9597 *	94.37	95.58	95.21	0.9497
		Class 2	81.61	89.49	86.62	0.8555	84.92	95.09	91.38	0.9000	87.63 *	94.06 *	91.72 *	0.9085 *	76.27	90.51	85.32	0.8339
		Class 2.5	77.81	92.37	88.84	0.8509	91.45 *	93.35 *	92.89 *	0.9240 *	89.16	93.96	92.80	0.9156	79.21	88.82	86.49	0.8402
		Class 3	66.79	98.78	96.04	0.8278	80.14	99.09	97.47	0.8962	80.51	99.32	97.71	0.8991	66.43	99.19	96.38	0.8281
	1.95–50 Hz	Class 0	88.63	93.62	92.09	0.9113	90.14	94.20	92.95	92.17	80.68	96.12	91.38	0.8840	85.61	93.40	91	0.8950
		Class 2	75.25	86.86	82.63	0.8106	75.59	87.45	83.12	81.52	79.49	82.29	81.27	0.8089	74.24	82.77	79.66	0.7851
		Class 2.5	75.64	92.53	88.44	0.8409	75.38	92.17	88.10	83.77	76.15	91.64	87.88	0.8389	66.20	92.86	86.40	0.7953
		Class 3	87.73	98.85	97.90	0.9329	87.73	98.88	97.93	93.31	82.31	99.53	98.05	0.9092	93.14 *	98.17 *	97.74 *	0.9566 *
15 s	0.83–1.95 Hz	Class 0	86.02	94.46	91.87	0.9024	92.40	95.34	94.44	0.9387	91.19	96.42	94.81	0.9380	86.02	94.60	91.96	0.9031
		Class 2	78.87	88.81	85.18	0.8384	84.25	92.78	89.67	0.8852	87.96	91.46	90.18	0.8971	76.70	88	83.87	0.8235
		Class 2.5	83.53	90.33	88.69	0.8693	86.05	95.13	92.94	0.9059	85.47	94.45	92.29	0.8996	76.16	91.44	87.75	0.8380
		Class 3	60.33	98.77	95.47	0.7955	86.41	98.77	97.71	0.9259	73.37	99.13	96.91	0.8625	81.52	97.49	96.12	0.8951
	1.95–50 Hz	Class 0	86.02	93.11	90.93	0.8957	84.50	95.81	92.33	0.9016	89.21	94.80	93.08	0.9201	88.91	90.34	89.90	0.8963
		Class 2	64.40	86.60	78.49	0.7550	77.98	83.58	81.53	0.8078	79.51	81.96	81.07	0.8074	68.76	82.70	77.81	0.7573
		Class 2.5	76.74	87.31	84.76	0.8203	70.93	91.19	86.30	0.8106	64.92	91.37	84.99	0.7815	62.98	91.62	84.71	0.7730
		Class 3	84.24	98.52	97.29	0.9138	82.07	98.52	97.10	0.9029	69.02	99.64	97.01	0.8433	80.98	98.52	97.01	0.8975
30 s	0.83–1.95 Hz	Class 0	83.80	96.91	92.84	0.9036	89.41	96.63	94.39	0.9302	86.92	96.49	93.52	0.9170	82.87	94.81	91.10	0.8884
		Class 2	80.47	83.97	82.69	0.8222	84.70	86.72	85.98	0.8571	86.28	85.65	85.88	0.8596	80.47	83.05	82.11	0.8176
		Class 2.5	64.20	91.40	85.01	0.7780	76.54	92.54	88.78	0.8454	76.13	91.91	88.20	0.8402	67.49	91.91	86.17	0.7970
		Class 3	83.52	96.50	95.36	0.9001	72.53	99.58	97.20	0.8605	59.34	99.36	95.84	0.7935	72.53	97.77	95.55	0.8515
	1.95–50 Hz	Class 0	75.70	94.39	88.59	0.8505	83.18	94.25	90.81	0.8871	79.44	94.95	90.14	0.8720	83.18	88.50	86.85	0.8584
		Class 2	68.60	78.32	74.76	0.7346	76.52	80.15	78.82	0.7833	70.18	80.15	76.50	0.7517	58.31	80.61	72.44	0.6946
		Class 2.5	62.55	87.74	81.82	0.7514	61.32	89.25	82.69	0.7529	67.49	86.22	81.82	0.7685	60.08	86.85	80.56	0.7347
		Class 3	82.42	97.35	96.03	0.8988	57.14	97.88	94.29	0.7751	63.74	98.30	95.26	0.8102	71.43	97.67	95.36	0.8455

Note: * selected by Youden’s index criteria as the best classification result.