Levels and predictors of participation in integrated treatment programs for pregnant and parenting women with problematic substance use

Table 3 Predictors of the first visit interval (number of days between the first and second visits)^a

Variable^b	Est.	S.E.	p	Incidence Rate Ratio	95% Confidence Interval		Predicted First Interval
Variable^b	Est.	S.E.	p	Incidence Rate Ratio	Lower	Upper	Predicted First Interval
Intercept	2.70	0.08	<.0001	.	.	.	.
Age	−0.01	0.00	<.0001	0.99	0.99	0.99	Age 25 = 12.5
							Age 40 = 10.8
Receiving social assistance:
Yes	0.07	0.03	0.01	1.07	1.01	1.14	12.5
No	(ref)	.	.	1.00	.	.	11.7
Alcohol problems:
Yes	0.09	0.03	0.001	1.09	1.03	1.16	12.6
No	(ref)	.	.	1.00	.	.	11.6
Opioid problems ^c:
Yes	0.10	0.03	0.0005	1.11	1.04	1.17	12.7
No	(ref)	.	.	1.00	.	.	11.5
Frequency of substance use, past 30 days:
Binge use	−0.13	0.07	0.07	0.87	0.77	1.01	11.4
3 times per week to daily	−0.13	0.03	<.0001	0.88	0.83	0.93	11.4
Up to 2 times per week	−0.03	0.04	0.41	0.97	0.90	1.05	12.6
No use	(ref)	.	.	1.00	.	.	13.0
Past-year injection drug use:
Yes	−0.14	0.04	0.001	0.87	0.80	0.94	11.3
No	(ref)	.	.	1.00	.	.	13.0
Treatment mandate:
Legal	0.25	0.06	<.0001	1.29	1.14	1.44	14.4
Child protection	0.07	0.03	0.02	1.07	1.07	1.01	12.0
Employer/school	−0.01	0.08	0.91	0.99	1.01	1.14	11.1
None	(ref)	.	.	1.00	.	.	11.2

^aNegative binomial regression with random effect for agency; includes one episode per client (first episode selected). N = 4200. Excludes 662 clients (12.8% of 5162) whose first episode consisted of only 1 visit, and excludes 300 clients (5.8% of 5162) with > 1 visit but missing values on predictor variables. AIC = 29,021.6, BIC = 29,040.8
^bCoefficients were not statistically significant for: education, employment status, marital status, cannabis problem, stimulant problem, legal system involvement, pregnant at admission
^cIncludes prescription opioids, heroin, opium, and over-the-counter codeine