Table 2.

Index values of each group and difference significance results.

	Chi-square	Healthy	Non-De	Mil-De	Con-De
	(Kruskal–Wallis rank test)
SEn_Fp1	54.07∗∗	0.6529 ± 0.0008	0.6610 ± 0.0011aa	0.6615 ± 0.0007aa	0.6576 ± 0.0009aabcc
SEn_Fz	61.67∗∗	0.6517 ± 0.0008	0.6596 ± 0.0010aa	0.6619 ± 0.0008aa	0.6594 ± 0.0009aa
SEn_Fp2	80.54∗∗	0.6507 ± 0.0008	0.6607 ± 0.0010aa	0.6616 ± 0.0007aa	0.6583 ± 0.0009aacc
LZC_Fp1	41.25∗∗	0.9191 ± 0.0014	0.9200 ± 0.0019	0.9290 ± 0.0012aabb	0.9276 ± 0.0014aabb
LZC_Fz	33.18∗∗	0.9217 ± 0.0015	0.9180 ± 0.0019	0.9278 ± 0.0011aabb	0.9289 ± 0.0014aabb
LZC_Fp2	50.32∗∗	0.9181 ± 0.0014	0.9194 ± 0.0020	0.9282 ± 0.0012aabb	0.9291 ± 0.0012aabb

¹ Feature values of each group and the results of difference analysis are shown in this table. Feature values are expressed as mean ± standard error (SE). ^∗∗Statistical difference significance among four groups with p < 0.01. ^aaSignificant difference compared with healthy group with p < 0.01.^bSignificant difference compared with Non-De group with p < 0.05. ^bbSignificant difference compared with Non-De group with p < 0.01. ^ccSignificant difference compared with Mil-De group with p < 0.01.