Table 3.

Comparison of contraceptive use at the time of enrollment among analysis sample for the Contraceptive CHOICE Project (CHOICE, 2007–2008) with the National Survey of Family Growth (NSFG, 2006–2008) and Behavioral Risk Factor Surveillance System for Missouri (BRFSS-MO, 2006).

	CHOICE and NSFG							CHOICE and BRFSS-MO

	CHOICE^a		NSFG		Absolute difference		Effect size	CHOICE^b		BRFSS-MO		Absolute difference		Effect size

	%	SE	%	SE	%	p value	Cohen’s h^c	%	SE	%	SE	%	p value	Cohen’s h^c
Vasectomy	0.1	0.1	8.3	0.7	−8.2	<0.01	0.52	0.3	0.3	13.1	1.6	−12.8	<0.01	0.63
Implant	0.02	0.02	0.08	0.05	−0.06	N/A	0.03	0.02	0.02	0.9	0.8	−0.9	N/A	0.17
IUD	0.9	0.4	4.9	0.6	−4.0	<0.01	0.26	0.3	0.1	1.7	0.9	−1.4	<0.01	0.14
Injectables	2.6	0.5	2.9	0.3	−0.3	<0.01	0.02	3.6	0.8	2.5	0.9	1.1	<0.01	0.06
Pill	16.1	1.2	24.0	1.0	−7.9	<0.01	0.20	16.8	1.8	19.8	2.4	−3.0	<0.01	0.08
Patch	0.7	0.2	0.6	0.1	0.1	0.32*	0.01	0.4	0.1	1.2	0.8	−0.8	<0.01	0.09
Ring	4.7	0.6	2.1	0.3	2.6	<0.01	0.15	5.0	0.7	0.9	0.5	4.1	<0.01	0.26
Condom	23.8	1.8	13.8	0.7	10.0	<0.01	0.26	20.4	2.1	12.9	2.0	7.5	<0.01	0.20
Diaphragm	0.1	0.1	0.06	0.04	0.04	0.29	0.01	0.1	0.1	0.5	0.4	−0.4	0.09	0.09
Rhythm	1.0	0.6	0.9	0.2	0.1	0.07	0.01	1.6	1.2	2.0	0.7	−0.4	<0.01	0.03
Withdrawal	5.8	0.7	4.7	0.5	1.1	<0.01	0.05	6.6	1.4	0.4	0.3	6.2	<0.01	0.39
Other	0.04	0.03	0.3	0.1	−0.26	N/A	0.07	0.04	0.03	2.0	0.9	−2.0	N/A	0.25
Non-users	44.2	2.0	37.1	1.1	7.1	<0.01	0.14	44.8	2.9	41.9	2.9	2.9	<0.01	0.06

Estimates are adjusted to NSFG for age and race/ethnicity.

Estimates are adjusted to Missouri BRFSS for age and race/ethnicity.

Cohen’s h: value of 0.20 is considered small, 0.50 medium and 0.80 large effect size.