This study has found that individuals in state-funded alcohol and other drug services in Texas who were coerced into treatment (69%) were less impaired and more likely to have completed treatment (42%), and be abstinent from cannabis at follow-up (84%) than their non-coerced peers.

At admission, clients who voluntarily entered treatment were less likely to be employed, to have sought care in an emergency room or hospital in the past year, to have used cannabis daily in the six months prior to admission, and to report more days of family, psychological, and drug and alcohol problems

This study found that 55% of all the clients met the criteria for cannabis dependence, a number close to the 60% findings of an Australian study of individuals diverted by police after arrest for cannabis-related offences [19]. Legally coerced clients were less impaired at admission, were more likely to stay in treatment longer and to complete treatment, and were less likely to leave against program advice but were more likely to be asked to leave as a result of rule violations. These findings are in contrast to a recent UK study that reported coerced clients were more likely to drop out of treatment [17]. Participants in that study who were legally coerced into treatment were also more likely to receive less intensive forms of treatment (outpatient counseling), to be contacted at follow-up, and to have not used in the month prior to that contact. The authors concluded that their coerced status contributed to their longer length of stay so that they were more likely to have successfully completed outpatient treatment. The differences in the study outcomes may be accounted for by differences in illicit drug use. The UK study does not report by principal drug of concern but appears to focus on injecting drug users [17]. These findings highlight the importance of assessing treatment outcome by principal drug of concern.

Having more days of psychological problems was a predictor of voluntary status at treatment admission, a predictor of non-completion of treatment, and a predictor of cannabis use at follow-up, regardless of legal status. Although the level of co-occurring disorders may be underreported in this dataset, the diagnoses of depression and anxiety, particularly among the voluntary clients, and the prescribing of medications for these conditions provides evidence that treatment of co-occurring conditions would be a factor in increasing positive treatment outcomes.

Family and friends affected treatment outcomes both positively and negatively. Having more days of family problems at admission was a predictor of voluntary status and it was a predictor of cannabis use at follow-up for both non-coerced and coerced clients. Individuals who had more family and friends involved in their treatment process were more likely to complete treatment, while, as expected, living in a household where the individuals were exposed to alcohol abuse or drug use predicted cannabis use at follow-up. The finding that having been in a residential program was associated with abstinence in the last month of treatment, completing treatment, but not being abstinent at follow-up may be related to the benefits of a more structured setting in treatment and the lack of a stable and sober living environment after treatment.

Employment was also an important factor in this study. At admission, coerced clients were more likely to be employed and to report fewer days of employment problems as measured on the ASI employment domain. At follow-up, both coerced and voluntary clients who reported more days of employment problems were more likely to be using cannabis. Likewise, more attendance at 12-step meetings was a significant predictor of treatment completion and abstinence from cannabis in the month preceding treatment discharge and in the month preceding 90-day follow-up.