Table 4. T-test/ANOVA results with the dmft and DMFT scores as dependent variable respectively.

Group		N	Primary teeth		Permanent teeth
			dmft (SD)	p value (F)*	DMFT (SD)	p value (F)**
Sibling	have	2,437	5.82 (4.11)	0.005	0.04 (0.29)	<0.001
	do not have	2,491	6.20 (4.32)	(7.915)	0.03 (0.22)	(14.768)
Father’s educational background	low (junior school or below)	2,347	6.23 (4.25)	<0.001	0.04 (0.28)	0.17
	median (senior school)	1,386	6.20 (4.17)	(761.893)	0.04 (0.29)	(0.236)
	high (college or above)	1,158	5.29 (4.13)		0.02 (0.17)
Mother’s educational background	low (junior school or below)	2,676	6.27 (4.21)	<0.001	0.04 (0.29)	0.073
	median (senior school)	1,242	6.03 (4.26)	(904.825)	0.03 (0.24)	(0.352)
	high (college or above)	941	5.13 (4.04)		0.02 (0.17)
Toothbrush habits	≥2/d	1,224	6.40 (4.52)	<0.001	0.02 (0.19)	0.001
	<2/d	3,710	5.88 (4.11)	(19.701)	0.04 (0.28)	(11.949)
Sweet consumption	≥2/d	590	6.80 (4.48)	<0.001	0.04 (0.29)	0.345
	1/d	1,541	6.16 (4.19)	(16.542)	0.04 (0.28)	(1.065)
	<1/d	2,784	5.75 (4.15)		0.03 (0.24)
Oral health awareness	good (7∼8)	741	5.82 (4.21)	0.248	0.02 (0.19)	0.363
	median (4∼6)	2,481	6.10 (4.21)	(1.394)	0.03 (0.26)	(1.014)
	poor (≤3)	1,686	5.98 (4.23)		0.04 (0.28)
Oral health attitude	good (3∼4)	4,489	6.00 (4.21)	0.326	0.03 (0.26)	0.263
	median (2)	330	5.97 (4.23)	(1.122)	0.05 (0.28)	(1.337)
	poor (≤1)	102	6.63 (4.49)		0.01 (0.10)

Notes.

^*p value of comparison of dmft.

^**p value of comparison of DMFT.