Deciduous dental caries status and associated risk factors among preschool children in Xuhui District of Shanghai, China

Table 1 Deciduous caries status of different age groups, genders and household registration types (n = 11,153)

Variables	Categories	Caries prevalence			dmft
Variables	Categories	No. of surveyed (No. of cases with dental caries)	Caries prevalence (%)	P-value (statistics¹)	Mean ± SD	P-value (statistics²)
Age (years old)	3	531 (156)	29.38	< 0.001** (−15.992^a)	1.09 ± 2.45	< 0.001** (304.022^b)
	4	3626 (1141)	38.91		1.68 ± 3.08
	5	3798 (1908)	50.24		2.45 ± 3.57
	6	3198 (1769)	55.31		2.71 ± 3.69
Gender	Boys	5972 (2818)	47.19	0.702 (0.146)	2.23 ± 3.43	0.574 (0.562^c)
Gender	Girls	5181 (2426)	46.82		2.19 ± 3.45
Household registration	Shanghai	10,700 (4959)	46.35	< 0.001** (47.890)	2.14 ± 3.38	< 0.001** (−8.806^d)
Household registration	Non-Shanghai	453 (285)	62.91		3.76 ± 4.43
Total	–	11,153 (5244)	47.02	–	2.21 ± 3.44	–

**P < 0.01. SD = standard deviation
¹a: Cochran-Armitage test for trend (the statistics is Z-value); the others were Pearson Chi-square test (the statistics is χ²-value)
²b: Kruskal-Wallis test (the statistics is χ²-value); c: t test (the statistics is t-value); d: Mann-Whitney test (the statistics is Z-value)

ISSN: 1472-6831