Prize-based contingency management for the treatment of substance abusers: a meta-analysis.

AIM: To review randomized controlled trials to assess efficacy of a prize-based contingency management procedure in reducing substance use (where a drug-free breath or urine sample provides a chance of winning a prize). METHODS: A meta-analysis was conducted on papers published from January 2000 to February 2013 to determine the effect size of studies comparing prize-based contingency management to a treatment-as-usual control condition (k = 19 studies). Parallel analyses evaluated the efficacy of both short- (k = nine studies) and long-term outcomes (k = six studies) of prize-based contingency management. RESULTS: The average end-of-treatment effect size (Cohen's d) was 0.46 [95% confidence interval (CI) = 0.37, 0.54]. This effect size decreased at the short-term (≤3-month) post-intervention follow-up to 0.33 (95% CI = 0.12, 0.54) and at the 6-month follow-up time-point there was no detectable effect [d = -0.09 (95% CI = -0.28, 0.10)]. CONCLUSION: Adding prize-based contingency management to behavioral support for substance use disorders can increase short-term abstinence, but the effect does not appear to persist to 6 months.

Contingency management for cocaine treatment: cash vs. vouchers.

The efficacy of contingency management (CM) for treating drug abuse is well supported. The most widely used form of CM is voucher-based reinforcement therapy (VBRT), where clients receive an escalating schedule of vouchers that can be redeemed for goods and services for meeting treatment goals. Though generally rejected due to concerns about potential harms to drug using participants, research suggests that cash may be a more effective reinforcer. This three-group randomized trial compared the efficacy of cash-based reinforcement therapy (CBRT) to VBRT and a non-CM condition on cocaine abstinence and treatment attendance; and examined whether CBRT resulted in greater levels of harm than VBRT. Findings indicated that the CBRT was as effective as VBRT when compared to the non-CM condition and that it did not increase rates of drug use, cravings, or high-risk behaviors. Future research should examine potential cost savings associated with a cash-based CM approach as this could have important implications for the wider adoption of the CM model.