Voucher-based Reinforcement Therapy Research Articles

The Efficacy of Contingency Management for Adolescent Cannabis Use Disorder: A Controlled Study

ABSTRACTBackground: This study was performed to investigate the efficacy of a voucher-based reinforcement therapy (VBRT) rewarding drug-free urine for adolescents with cannabis use disorder. Methods: A controlled 10-week study where 59 adolescents aged 14–18 years were assigned by cohorts into groups of either an integrated cognitive-behavioral therapy (CBT) and VBRT or CBT with attendance-based reward program. Substance use was monitored by twice-weekly urinalysis. Other measures were collected at pre- and posttreatment and at 3-month follow-up. Results: There was no significant difference in the linear change between conditions for cannabis use either from Sessions 1 to 10 or between end-of-treatment to 3-month follow-up. Also, self-efficacy and coping response did not show improvement during treatment. Conclusions: In this study, the addition of contingency management (CM) to CBT in youth was not found to be more efficacious than similar compensation rewarding attendance only. Continued examination of the efficacy of CM and its interaction with the associated mechanisms of behavior change of CBT in youth is necessary. Examination of the effect of the magnitude of the reward as well as considering the emotional and cognitive developmental differences from adults is warranted.

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.

Randomized clinical trial examining duration of voucher-based reinforcement therapy for cocaine abstinence

BackgroundThis is the first study to systematically manipulate duration of voucher-based reinforcement therapy (VBRT) to see if extending the duration increases abstinence during and following VBRT. MethodsWe randomized cocaine-dependent methadone-maintained adults to Standard (12 weeks; n=62) or Extended (36 weeks; n=68) VBRT and provided escalating voucher amounts contingent upon urinalysis verification of cocaine abstinence. Urinalysis was scheduled at least every 2 weeks during the 48-week study and more frequently during VBRT (3/week) and 12 weeks of Aftercare (2/week). ResultsExtended VBRT produced longer durations of continuous cocaine abstinence during weeks 1–24 (5.7 vs 2.7 weeks; p=0.003) and proportionally more abstinence during weeks 24–36 (X2=4.57, p=.03, OR=2.18) compared to Standard VBRT. Duration of VBRT did not directly predict after-VBRT abstinence; but longer continuous abstinence during VBRT predicted abstinence during Aftercare (p=0.001) and during the last 12 weeks of the study (p<0.001). Extended VBRT averaged higher monthly voucher costs compared to Standard VBRT ($96 vs $43, p<.001); however, the average cost per week of abstinence attained was higher in the Standard group ($8.06 vs $5.88, p<.001). Participants in the Extended group with voucher costs exceeding $25 monthly averaged 20 weeks of continuous abstinence. ConclusionsGreater abstinence occurred during Extended VBRT, but providing a longer duration was not by itself sufficient to maintain abstinence after VBRT. However, if abstinence can be captured and sustained during VBRT, then providing longer durations may help increase the continuous abstinence that predicts better long-term outcomes.

Resets do not appear to increase the rate of adverse events or prolong relapse in voucher-based reinforcement therapy

Voucher-based reinforcement therapy (VBRT) is an efficacious contingency management intervention for substance use disorders that provides escalating voucher values to reinforce continuous abstinence and typically resets escalated values to the initial low level upon detection of drug use. The objective of this study involving 130 methadone-maintained outpatients receiving VBRT was to investigate whether resets (a) increase risk for adverse events (AEs) and (b) delay return to abstinence in relation to magnitude of voucher reset. Weeks following resets were examined for increased likelihood of AEs using a Poisson regression. A Cox proportional hazards model was used to determine if higher resets increased the number of days until a negative urine specimen. Results showed that resets did not increase the likelihood of AEs nor were higher resets related to an increased delay to abstinence. Research involving larger samples is needed to produce sufficient data directly addressing safety concerns of various treatment stakeholders.

Extended Voucher-based Reinforcement Therapy for Long-term Drug Abstinence

To determine whether longer durations of voucher-based reinforcement therapy (VBRT) increase long-term abstinence compared to standard durations. Cocaine-abusing or dependent methadone-maintenance patients (N = 130) were randomized to receive either Standard (12-week; n = 62) or Extended (36-week; n = 68) VBRT. Participants provided 3 urine samples weekly during VBRT, and each cocaine-negative sample produced a voucher exchangeable for goods and services. Extended VBRT produced longer durations of self-reported continuous abstinence during study Year 1 (M = 74 vs. 46 days; F(1,128) = 5.23, P = 0.024), but not during Year 2. However, each week of abstinence during Year 1 was associated with an increase of 9.19 days of abstinence during Year 2, regardless of study condition (t(1) = 4.92, P < 0.001). Longer-duration VBRT can increase abstinence during VBRT, but may not maintain it afterwards. However, longer during-treatment abstinence begets later abstinence suggesting that further research regarding this relationship is needed.

Effects of voucher‐based incentives on abstinence from cigarette smoking and fetal growth among pregnant women

This study examined whether voucher-based reinforcement therapy (VBRT) contingent upon smoking abstinence during pregnancy is an effective method for decreasing maternal smoking during pregnancy and improving fetal growth. A two-condition, parallel-groups, randomized controlled trial was conducted in a university-based research clinic. A total of 82 smokers entering prenatal care participated in the trial. Participants were assigned randomly to either contingent or non-contingent voucher conditions. Vouchers exchangeable for retail items were available during pregnancy and for 12 weeks postpartum. In the contingent condition, vouchers were earned for biochemically verified smoking abstinence; in the non-contingent condition, vouchers were earned independent of smoking status. Smoking outcomes were evaluated using urine-toxicology testing and self-report. Fetal growth outcomes were evaluated using serial ultrasound examinations performed during the third trimester. Contingent vouchers significantly increased point-prevalence abstinence at the end-of-pregnancy (41% versus 10%) and at the 12-week postpartum assessment (24% versus 3%). Serial ultrasound examinations indicated significantly greater growth in terms of estimated fetal weight, femur length and abdominal circumference in the contingent compared to the non-contingent conditions. These results provide further evidence that VBRT has a substantive contribution to make to efforts to decrease maternal smoking during pregnancy and provide new evidence of positive effects on fetal health.

The Search for Medications to Treat Stimulant Dependence

Progress in understanding the neurobiology of stimulant dependence has enabled researchers to identify medications whose pharmacological effects suggest that they might help patients initiate abstinence or avoid relapse. Several of these medications and a vaccine have shown encouraging results in controlled clinical trials with cocaine-dependent patients. The search for a medical treatment for methamphetamine dependence started more recently, due to the later emergence of this epidemic, but at least one candidate medication has shown promise in early clinical testing. Treatment approaches that combine efficacious medications and empirically proven behavioral interventions, such as voucher-based reinforcement therapy, will almost certainly produce the best results.

Levodopa pharmacotherapy for cocaine dependence: Choosing the optimal behavioral therapy platform

Background The dopamine precursor levodopa has shown some, albeit relatively weak, promise in treating cocaine dependence. This study sought to identify the most appropriate behavioral therapy platform for levodopa pharmacotherapy by evaluating its effect when administered in combination with behavioral platforms of varying intensities. Method A total of 161 treatment-seeking cocaine dependent subjects received sustained release levodopa/carbidopa (400/100 mg bid, Sinemet) or placebo delivered in combination with Clinical Management (ClinMan); ClinMan + cognitive behavioral therapy (CBT); or ClinMan + CBT + voucher-based reinforcement therapy (VBRT) in a 12-week randomized, placebo-controlled, double-blind (for medication condition) trial. Medication compliance was monitored with riboflavin (100 mg/capsule) and the Medication Event Monitoring System. Protocol compliance was addressed in weekly, 10-min nurse-delivered ClinMan sessions. Weekly, 1-h CBT sessions focused on coping skills training. VBRT (with escalating reinforcer value) provided cash-valued vouchers contingent on cocaine-negative urine toxicology results. Urine benzoylecgonine assays collected thrice-weekly were analyzed by intention-to-treat criteria using generalized linear mixed models. Results Levodopa main effects were found on all outcome measures of cocaine use. Contrasts testing the levodopa-placebo difference within each behavioral platform found reliable effects, favoring levodopa, only in the VBRT platform. Levodopa treatment with vouchers produced higher proportions of cocaine-negative urines and longer periods of consecutive abstinence compared to other treatment combinations. Conclusion This is the first study to find a significant treatment effect for levodopa and, in doing so, to demonstrate that the magnitude of this effect is dependent upon conditions of the behavioral therapy platform. The data support use of levodopa with abstinence-based reinforcement therapy as one efficacious combination in cocaine dependence disorder treatment.

A meta‐analysis of voucher‐based reinforcement therapy for substance use disorders

To systematically investigate the effectiveness of voucher-based reinforcement therapy for the treatment of substance use disorders. Effect sizes and 95% confidence intervals were calculated for studies published between January 1991 and March 2004 that utilized voucher-based reinforcement therapy (VBRT) or related monetary-based incentives to treat substance use disorders (SUDs). Thirty studies involved interventions targeting abstinence from drug use using experimental designs where effects on treatment outcome could be attributed to the VBRT intervention. The estimated average effect size (r) for those studies was 0.32 (95% CI 0.26-0.38). Analyses of variables thought to moderate VBRT effect sizes revealed that more immediate voucher delivery and greater monetary value of the voucher were associated with larger effect sizes. Additional studies were identified wherein VBRT was used to target clinic attendance (n = 6) or medication compliance (n = 4). VBRT studies targeting attendance produced average effect sizes of 0.15 (95% CI 0.02-0.28), while those that targeted medication compliance produced an average effect of 0.32 (95% CI 0.15-0.47). No significant moderators were identified for these 10 studies. Overall, VBRT generated significantly better outcomes than did control treatments. These results further support the efficacy of VBRT, quantify the magnitude of its effects, identify significant moderators and suggest potential directions for future research.

Investigating the use of contingency management in the treatment of cocaine abuse among individuals with schizophrenia: a feasibility study

This small-scale study was conducted to examine the feasibility of using voucher-based reinforcement therapy (VBRT) as a treatment modality for cocaine abuse among individuals with schizophrenia. Cocaine use was reduced in three individuals with a diagnosis of schizophrenia during a VBRT intervention. Interestingly, all of the abstinence occurred during the first half of the intervention. This early period of sobriety may represent a clinically relevant window of opportunity during which intensive psychosocial or social work interventions might have a greater chance for success.

Treatment of heroin-dependent poly-drug abusers with contingency management and buprenorphine maintenance.

This study targeted poly-drug (cocaine plus heroin) abstinence among buprenorphine-maintained participants with a 12-week voucher-based reinforcement therapy (VBRT) phase versus a yoked control condition. Baseline levels of cocaine and heroin use were significant predictors of treatment outcome, regardless of treatment assignment. Overall, there were no significant group differences on treatment outcome. However, among the subsample that produced one or more poly-drug-free urine results, VBRT participants had significantly increased cocaine-but not heroin and poly-drug-abstinence, although all results were in the predicted direction. Results suggest that for those who achieve poly-drug abstinence, VBRT may enhance treatment outcome. However, improved interventions, perhaps targeting single-drug abstinence, increasing reinforcement magnitude, or both, may be necessary to promote initial poly-drug abstinence in this population.

The influence of exchange delays on cigarette versus money choice: A laboratory analog of voucher-based reinforcement therapy.

The influence of exchange delays on cigarette versus money choice: A laboratory analog of voucher-based reinforcement therapy.

Increasing opiate abstinence through voucher-based reinforcement therapy

Heroin dependence remains a serious and costly public health problem, even in patients receiving methadone maintenance treatment. This study used a within-subject reversal design to assess the effectiveness of voucher-based abstinence reinforcement in reducing opiate use in patients receiving methadone maintenance treatment in an inner-city program. Throughout the study subjects received standard methadone maintenance treatment involving methadone, counseling, and urine monitoring (three times per week). Thirteen patients who continued to use opiates regularly during a 5-week baseline period were exposed to a 12-week program in which they received a voucher for each opiate-free urine sample provided; the vouchers had monetary values that increased as the number of consecutive opiate-free urines increased. Subjects continued receiving standard methadone maintenance for 8 weeks after discontinuation of the voucher program (return-to-baseline). Tukey's posthoc contrasts showed that the percentage of urine specimens that were positive for opiates decreased significantly when the voucher program was instituted ( P ≤ 0.01) and then increased significantly when the voucher program was discontinued during the return-to-baseline condition ( P ≤ 0.01). Rates of opiate positive urines in the return-to-baseline condition remained significantly below the rates observed in the initial baseline period ( P ≤ 0.01). Overall, the study shows that voucher-based reinforcement contingencies can decrease opiate use in heroin dependent patients receiving methadone maintenance treatment.