Table 3.

Relative risk of sterilization from Cox proportional hazards models assessing associations between selected variables and respondent’s use of sterilization.

	Female sample (N=10,629)						Male sample (N=8,615)
	Model 1		Model 2		Model 3		Model 1		Model 2		Model 3
	RR	95% CI	RR	95% CI	RR	95% CI	RR	95% CI	RR	95% CI	RR	95% CI
Marital status		***		**		*		***		***		***
Never-married single	0.24	0.18 – 0.32	0.79	0.60 – 1.02	0.70	0.54 – 0.92	0.06	0.02 – 0.17	0.21	0.08 – 0.59	0.28	0.10 – 0.79
Ever-married single	1.15	0.84 – 1.59	1.13	0.82 – 1.57	1.05	0.75 – 1.49	0.28	0.15 – 0.53	0.31	0.17 – 0.57	0.33	0.18 – 0.61
Never-married cohabitation	1.07	0.83 – 1.36	1.16	0.90 – 1.51	1.11	0.85 – 1.45	0.02	0.00 – 0.09	0.02	0.00 – 0.11	0.04	0.01 – 0.23
Ever-married cohabitation	1.37	0.96 – 1.96	1.05	0.66 – 1.64	0.91	0.56 – 1.49	0.31	0.06 – 1.65	0.30	0.06 – 1.64	0.35	0.06 – 1.96
First-order marriage	Ref	Ref	Ref	Ref	Ref	Ref	Ref	Ref	Ref	Ref	Ref	Ref
Higher-order marriage	1.81	1.45 – 2.27	1.61	1.23 – 2.13	1.46	1.09 – 1.95	1.48	0.87 – 2.53	1.28	0.74 – 2.20	1.20	0.69 – 2.11

Note: Model 1 estimates the unadjusted relative risk of sterilization by marital status. Model 2 estimates the relative risk of sterilization by marital status while controlling for parity. Model 3 estimates the relative risk of sterilization by marital status while controlling for parity, early childbearing, education, race and ethnicity, nativity, and historical period.

Symbols in the first row indicate significance of association between the variable marital status and risk of sterilization (based on Wald tests; *** p < .001, ** p < .01, * p < .05).

RR = relative risk, CI = confidence interval, Ref = reference category.