Table 6.

Relationship between erupted permanent tooth number and the significant independent variables among 12-year-olds in four final models.

Independent variables	Estimate Coefficient	S.E. (Coefficient)	P
Model 1 (R2 = 0.116, adjusted R2 = 0.111)
W/H z-score	0.11	0.14	< 0.001***
Gender
Girl	0.68	0.18	< 0.001***
Boya
Parents' highest education attainment			0.004**
> HK$ 40,000 (1)	−0.99	0.39	(1) < (3)*
HK$ 10,000-HK$ 40,000 (2)	−0.29	0.35
< HK$ 10,000a (3)
Intercept	22.9	0.57	< 0.001***
Model 2 (R2 = 0.098, adjusted R2 = 0.093)
BMI z-score	0.17	0.02	< 0.001***
Gender
Girl	0.62	0.18	0.001**
Boya
Parents' highest education attainment			0.004**
Post-secondary or above (1)	−0.973	0.40	(1) < (3)*
Secondary school (2)	−0.268	0.36
Primary school graduate or below# (3)
Intercept	23.1	0.61	< 0.001***
Model 3 (R2 = 0.107, adjusted R2 = 0.101)
WC z-score	0.07	0.01	< 0.001***
Gender
Girl	0.78	0.19	< 0.001***
Boya
Parents' highest education attainment			0.007**
Post-secondary or above (1)	−0.27	0.39	(1) < (3)*
Secondary school (2)	−0.93	0.36
Primary school graduate or below# (3)
Intercept	21.2	0.80	< 0.001***
Model 4 (R2 = 0.044, adjusted R2 = 0.038)
WHR z-score	4.80	1.75	0.006**
Gender
Girl	0.69	0.20	< 0.001***
Boya
Parents' highest education attainment			0.003**
Post-secondary or above (1)	−0.97	0.41	(1) < (3)*
Secondary school (2)	−0.22	0.37
Primary school graduate or below# (3)
Intercept	22.4	1.51	< 0.001***

BMI = body mass index; HK = Hong Kong; WC = waist circumference; W/H = weight-height ratio; WHR = waist-hip ratio.

*P < 0.05.

**P < 0.01.

***P < 0.001.

^aReference group.