Table 4.

Caries risk factors of the 5-year-old children (zero-inflated model, n = 459)

Zero-inflated portion (dmft = 0)	Variables	OR	p-value	95% C.I.
	Frequency of sugary snack intake		0.010
	≤2 per day	1.982		1.177–3.336
	>2 per day*
	Dental attendance experience		0.005
	Yes, regularly	0.749	0.512	0.315–1.779
	Yes, not regularly	0.276	0.001	0.127–0.595
	No *
	Family monthly income		0.002
	≥ HK$ 30,001	3.353	<0.001	1.725–6.521
	HK$ 15,001–30,000	1.675	0.100	0.907–3.096
	HK$ ≤15,000*
Negative binomial portion (dmft > 0)	Variables	IRR	p-value	95% C.I.
	Dental attendance experience		<0.001
	Yes, regularly	1.772	0.001	1.267–2.480
	Yes, not regularly	1.909	<0.001	1.495–2.438
	No *
	Parental dental knowledge		0.005
	Low	1.195	0.283	0.863–1.653
	Moderate	1.508	0.001	1.171–1.942
	High*
	Primary caregiver		0.026
	Grandparents	1.334	0.034	1.022–1.742
	Domestic helpers	0.690	0.067	0.466–1.027
	Parents*

*Reference group