Table 3. Poisson analysis of the exclusive use of bottle feeding in children aged under one year and age-adjusted prevalence ratio. State capitals and Federal District, Brazil, 2008.

Variable	Total Na	Exclusive use of baby bottles (%)	PRadjusted	95%CI	p
Distal block (1)
Maternal age (years)					0.274b
20 to 35	12,127	40.6	1
< 20	4,243	42.0	1.02	0.96;1.08	0.433
> 35	1,897	44.5	1.07	0.98;1.15	0.090
Maternal education (years)					0.008b
> 12	2,419	44.7	1
9 to 12	8,725	41.4	0.93	0.87;1.00	0.073
0 to 8	7,036	40.3	0.90	0.83;0.96	0.006
Maternal work					< 0.001b
Not working outside the home	12,171	39.0	1
On maternity leave	1,985	26.6	0.99	0.88;1.12	0.953
Working outside the home	3,089	60.3	1.40	1.33;1.48	< 0.001
Primiparity
No	9,424	38.7	1
Yes	8,501	44.3	1.13	1.07;1.19	< 0.001
Intermediate block (2 to 3)
Type of delivery
Normal/Forceps	10,526	41.6	1
Cesarean	9,698	45.0	1.08	1.03;1.13	0.001
Child gender
Female	10,287	42.3	1
Male	10,137	44.2	1.01	0.97;1.06	0.488
Low birth weight (< 2,500 g)
No	18,188	42.4	1
Yes	1,711	49.6	1.18	1.09;1.27	< 0.001
Born in Baby-Friendly Hospital
Yes	6,993	41.9	1
No	11,881	44.2	1.05	1.00;1.10	0.050
Routine health care services
Family Health Strategy	5,129	42.1	1
Basic health care unit	6,371	41.6	0.96	0.90;1.02	0.252
Private health care services	6,854	47.3	1.08	1.02;1.14	0.008
Proximal block (4A)
Breastfed within the first hour after birth
Yes	13,793	24.9	1
No	5,485	38.7	1.55	1.15;2.09	0.003
Proximal block (4B)
Breastfed on the first day after hospital discharge
Yes	7,467	24.9	1
No	197	38.7	1.50	1.12;2.03	0.007
Consumed processed milk on the first day after hospital discharge
No	7,007	22.8	1
Yes	580	51.4	2.20	1.91;2.52	< 0.001
Consumed water on the first day after hospital discharge
No	7,318	24.6	1
Yes	266	41.3	1.54	1.21;1.94	< 0.001
Consumed tea on the first day after hospital discharge
No	7,079	23.3	1
Yes	493	52.2	2.15	1.86;2.49	< 0.001

^a This analysis included exclusively users of baby bottles and nonusers of artificial nipples.

^b Linear trend test.