Table 3.

Multivariate logistic regression model for vitamin D deficiency and insufficiency (25(OH)D < 30 ng/ml) in 1218 children aged from 6 months to 14 years, south-west China, 2011

Factor	Adjusted OR	95 % CI	P value
Gender
Male	1·00	Ref.
Female	1·06	0·82, 1·38	0·655
Age group
<1 year	1·00	Ref.
1–3 years	3·07	2·07, 456	<0·001
4–7 years	12·16	7·61, 19·44	<0·001
8–14 years	18·29	10·14, 32·99	<0·001
Season of blood sampling*
Spring	1·00	Ref.
Summer	0·60	0·42, 0·87	<0·001
Autumn	0·62	0·41, 0·88	0·02
Winter	0·92	0·59, 1·44	0·924
Hb (continuous, g/dl)	0·52	0·99, 0·97	0·062
Pb (continuous, μg/dl)	1·01	1·00, 1·02	0·045

25(OH)D, 25-hydroxyvitamin D; Ref., reference category.

*Spring = March to May; summer = June to August; autumn = September to November; winter=December to February.