Receipt of Prescribed Controlled Substances by Adolescents and Young Adults Prior to Presenting for Opiate Dependence Treatment

Table 1

Multivariate^a negative binomial regression predicting the total number of prescriptions for controlled substances filled in the 2 years prior to presenting for outpatient medication-assisted treatment for opiate dependence.

Parameter	Parameter estimate^b	95% confidence interval		P value
Intercept	1.638	1.053	2.224	<0.0001
Type of opiate dependence
Heroin only	−0.900	−1.522	−0.278	0.005
Heroin + Rx opiate	−0.866	−1.613	−0.119	0.023
Rx opiate only	Reference	—	—
Gender
Female	0.711	0.143	1.278	0.014
Male	Reference	—	—
Dispersion	2.204	1.627	2.986

^aEligible covariates included age, gender, and type of opiate dependence.
^bThe negative binominal dispersion parameter was estimated by maximum likelihood.