Table 3. Socio-demographic and reproductive characteristics of women users of Basic Health Units, according to the level of knowledge about the IUD*. São Paulo, SP, Aracaju, SE and Cuiabá, MT, Brasil, 2015-2017.

Variables	Level of knowledge about the IUD* †
	≤ median		> median		p	ORa‡	95% CI§
	n	%	n	%
City
São Paulo	479	51.7	478	51.3	0.945	1.00	-
Aracaju	217	24.9	224	24.1		1.30	1.01-1.66
Cuiabá	231	23.4	229	24.6		1.02	0.80-1.31
Age (years)
18-24	282	30.4	214	23.0	<0.001	1.00	-
25-29	213	23.0	212	22.8		1.17	0.89-1.55
30-34	155	16.7	215	23.1		1.59	1.18-2.15
35 or more	277	29.9	290	31.1		1.20	0.90-1.61
Race/skin color
White	193	20.8	276	29.7	<0.001	1.00	-
Brown	506	54.6	458	49.3		0.67	0.53-0.86
Black	172	18.6	151	16.3		0.63	0.46-0.85
Asian/indigenous	55	5.9	44	4.7		0.59	0.37-0.93
Level of education (years)
Up to 8	298	32.1	170	18.3	<0.001	1.00	-
9-11	552	59.6	547	58.7		1.88	1.48-2.40
12 or more	77	8.3	214	23.0		4.84	3.38-6.91
Paid job
No	450	48.5	417	44.8	0.105	1.00	-
Yes	477	51.5	514	55.2		0.99	0.81-1.21
Health insurance
No	791	85.3	739	79.4	0.001	1.00	-
Yes	136	14.7	192	20.6		1.26	0.96-1.64
Stable relationship
No	235	25.3	244	26.2	0.673	1.00	-
Yes	692	74.7	687	73.8		1.00	0.80-1.26
Number of children
None	194	20.9	213	22.9	0.005	1.00	-
One	354	38.2	318	34.1		0.88	0.67-1.16
Two	200	21.6	255	27.4		1.34	0.96-1.87
Three or more	179	19.3	145	15.6		0.99	0.68-1.45
Previous abortion
No	722	77.9	704	75.6	0.247	1.00	-
Yes	205	22.1	227	24.4		1.11	0.88-1.41
Reproductive intention
Wants (more) children	312	33.7	311	33.4	0.983	0.94	0.74-1.21
Does not want (more) children	556	60.0	562	60.4		1.00	-
Does not know	59	6.3	58	6.2		0.89	0.58-1.35
Current or previous use of IUD*
No	911	98.3	848	91.1	<0.001	1.00	-
Yes	16	1.7	83	8.9		4.92	1.84-13.16
Total	927	49.9	931	50.1

^*IUD = Intrauterine device;

^†Hosmer-Lemeshow Test (p=0.2376);

^‡ORa = Adjusted odds ratio;

^§CI = Confidence interval