"Our study had two primary findings. First, we found that most study participants were motivated for treatment, despite not accessing it in at least the past 6 months (as per trial entry criteria). This may be the result of a lack of accessible or attractive treatment options available to them. Second, we found that baseline motivation for treatment did not predict retention in either HAT [heroin assisted treatment] or MMT [methadone maintenance treatment], however motivated patients receiving HAT were more likely to achieve response than unmotivated patients. While HAT is likely to retain patients regardless of motivational status, success in treatment, in terms of decreases in illicit drug use and crime, is more likely among motivated patients, as measured in our study. Further, HAT was statistically significantly more effective than MMT on each of the outcomes assessed."
Nosyk, B., Geller, J., Guh, D. P., Oviedo-Joekes, E., Brissette, S., Marsh, D. C., Schechter, M. T., & Anis, A. H. (2010). The effect of motivational status on treatment outcome in the North American Opiate Medication Initiative (NAOMI) study. Drug and alcohol dependence, 111(1-2), 161–165. doi.org/10.1016/j.drugalcdep.2010.03.019