Table 2. Arch index of 3 groups.

Left foot	Group	Group	Mean difference	Std.error	Sig.(a)	95% confidence interval for difference(2)
						Lower bound	Upper bound
	Mild	Mild
		Severe	−3.93(*)	0.39	0.00	−4.73	−3.14
		Normal	0.79	0.39	0.05	0.00	1.59
	Severe	Mild	3.93(*)	0.39	0.00	3.14	4.73
		Severe
		Normal	4.73(*)	0.39	0.00	3.93	5.52
	Normal	Mild	−0.79	0.39	0.05	−1.59	0.00
		Severe	−4.73(*)	0.39	0.00	−5.52	−3.93
		Normal
Right foot	Group	Group	Mean difference	Std.error	Sig.(a)	95% confidence interval for difference(2)
						Lower bound	Upper bound
	Mild	Mild
		Severe	−4.46(*)	0.28	0.00	−5.02	−3.91
		Normal	0.39	0.28	0.17	−0.17	0.95
	Severe	Mild	4.46(*)	0.28	0.00	3.91	5.02
		Severe
		Normal	4.85(*)	0.28	0.00	4.29	5.41
	Normal	Mild	−0.39	0.28	0.17	−0.95	0.17
		Severe	−4.85(*)	0.28	0.00	−5.41	−4.29
		Normal

Based on estimated marginal means.

*The mean difference is significant at the 0.05 level.

Mild: mild flexible flatfoot; Severe: severe flexible flatfoot; Normal: normal foot