Table 3. Descriptive statistics of patient-centered variables of questions 3 and 4 at five assessment times in the two groups using the Visual Analog Scale and the results of significance test†.

^†Employing independent samples t-test or Mann-Whitney test. SD: standard deviation, Min: minimum, Max: maximum, CI: confidence interval, T1: 24 hours after the beginning of the expansion, T2: 7 days after, T3: 15 days after, T4: 1 month after, T5: 4 months after the onset of expansion, RME: rapid maxillary expansion, SME: slow maxillary expansion, (NS): there was no statistically significant difference at P > 0.05, (*): there was a statistically significant difference at P < 0.001.

	Group	Mean	SD	Min	Max	95% CI for difference		P-value	Significance
						Lower bound	Upper bound
Q3: Swallowing difficulties
T1 (24 h)	RME	25.21	12.71	16.25	34.00	22.99	27.42	<0.001	*
	SME	12.69	3.64	8.50	22.00	11.18	14.19
T2 (7 d)	RME	23.21	12.72	14.25	32.00	20.99	25.42	<0.001	*
	SME	10.69	3.64	6.50	20.00	9.18	12.19
T3 (15 d)	RME	22.71	12.32	13.75	31.50	20.49	24.92	<0.001	*
	SME	10.19	3.64	6.00	19.50	8.68	11.69
T4 (1 m)	RME	22.51	5.46	13.55	31.30	20.29	24.72	<0.001	*
	SME	9.90	3.65	5.50	19.30	8.39	11.41
T5 (4 m)	RME	0.29	5.03	0.00	2.00	0.00	0.58	0.194	(NS)
	SME	0.95	1.94	0.00	8.00	0.14	1.75
Q4: Pressure on soft tissue
T1 (24 h)	RME	27.74	7.57	21.00	48.00	27.74	24.74	0.850	(NS)
	SME	24.36	4.93	8.50	22.00	22.32	26.39
T2 (7 d)	RME	64.22	11.73	19.00	86.00	59.57	68.86	<0.001	*
	SME	21.36	4.93	6.50	20.00	19.32	23.39
T3 (15 d)	RME	58.33	11.30	16.00	80.00	53.86	62.803	<0.001	*
	SME	18.36	4.93	6.00	19.50	16.32	20.39
T4 (1 m)	RME	7.70	6.758	0.00	27.00	5.03	10.37	0.208	(NS)
	SME	8.64	4.69	5.50	19.30	6.70	10.57
T5 (4 m)	RME	0.07	0.26	0.00	1.00	−0.03	0.17	0.188	(NS)
	SME	0.20	0.40	0.00	8.00	0.03	0.36