Table 2.

Comparison of regression performances of the competing methods in terms of Correlation Coefficient (CC) and Root Mean Square Error (RMSE)

Feature	Method		AD vs. NC				MCI vs. NC				MCI-C vs. MCI-NC
			ADAS-Cog		MMSE		ADAS-Cog		MMSE		ADAS-Cog		MMSE
			CC	RMSE	CC	RMSE	CC	RMSE	CC	RMSE	CC	RMSE	CC	RMSE
MRI	MRI-N		0.587	4.96	0.520	2.02	0.329	4.48	0.309	1.90	0.420	4.10	0.441	1.51
	MRI-S		0.591	4.85	0.566	1.95	0.347	4.27	0.367	1.64	0.426	4.01	0.482	1.44
	HOGM		0.625	4.53	0.598	1.91	0.352	4.26	0.371	1.63	0.435	3.94	0.521	1.41
	M3T		0.649	4.60	0.638	1.91	0.445	4.27	0.420	1.66	0.497	4.01	0.550	1.41
	Proposed		0.669	4.43	0.679	1.79	0.472	4.23	0.500	1.62	0.589	3.83	0.603	1.40
PET	PET-N		0.597	4.86	0.514	2.04	0.333	4.34	0.331	1.70	0.382	4.08	0.452	1.50
	PET-S		0.620	4.83	0.593	2.00	0.356	4.26	0.359	1.69	0.437	4.00	0.478	1.48
	HOGM		0.600	4.69	0.515	1.99	0.360	4.21	0.368	1.67	0.430	4.03	0.523	1.41
	M3T		0.647	4.67	0.593	1.92	0.447	4.24	0.432	1.68	0.520	3.91	0.569	1.45
	Proposed		0.671	4.41	0.620	1.90	0.513	4.13	0.485	1.66	0.526	3.87	0.570	1.37