
Another study supports the effects of twelve step participation over 24 months. (I know the abstract says “self help”, but the pay-walled article makes it clear that they were looking at twelve step participation.)
Abstract
The goal was to identify factors that predicted sustained cocaine abstinence and transitions from cocaine use to abstinence over 24 months. Data from baseline assessments and multiple follow-ups were obtained from three studies of continuing care for patients in intensive outpatient programs (IOPs). In the combined sample, remaining cocaine abstinent and transitioning into abstinence at the next follow-up were predicted by older age, less education, and less cocaine and alcohol use at baseline, and by higher self-efficacy, commitment to abstinence, better social support, lower depression, and lower scores on other problem severity measures assessed during the follow-up. In addition, higher self-help participation, self-help beliefs, readiness to change, and coping assessed during the follow-up predicted transitions from cocaine use to abstinence. These results were stable over 24 months. Commitment to abstinence, self-help behaviors and beliefs, and self-efficacy contributed independently to the prediction of cocaine use transitions. Implications for treatment are discussed.
It’s worth noting that some of these factors predicting abstinence are enhanced by twelve step participation:
These models represented fairly stringent tests of the predictive power of the time varying variables, as they controlled for both baseline (i.e., early treatment) cocaine use and cocaine use status at the time the predictor variables were assessed. In analyses that included multiple time-varying predictors and baseline cocaine use, the variables that contributed independently to the prediction of transitions in cocaine use states were self-efficacy, self-help participation (for those who were currently using cocaine), commitment to abstinence, and self-help beliefs. Three of these four variables assessed self-help group related factors, which highlights the important role that self-help involvement and beliefs play in sustained recoveries in this population.