Voucher-based Contingency Management Research Articles

Decision-making tendencies and voucher spending independently support abstinence within contingency management for methamphetamine use disorder.

Decision-making tendencies and spending within cash voucher-based interventions have individually been shown to be related to future abstinence among participants with methamphetamine use disorder (MUD), but less is known of their independent contributions. This study of participants in a contingency management (CM) trial investigated whether decision-making and spending were each associated with future abstinence. Thirty-two outpatients with MUD, predominately male (68%) and mixed ancestry (94%) with a median age of 34 years, participated in an 8-week cash voucher-based CM pilot trial. Prior to commencing the trial, participants completed a computerized Iowa Gambling Task (IGT) to measure decision-making preferences for more frequent rewards and longer term gains of greater magnitude. Spending and abstinence of participants were tracked over the duration of the trial. In a secondary analysis, time-lagged counting process Cox Proportional Hazard models were conducted. Baseline decision-making, characterized by a preference for frequent rewards, was associated with a greater likelihood of future spending, Hazard Ratio; HR = 1.13 [1.06: 1.21]. Avoidance of short-term rewards to realize longer term, higher magnitude rewards, and spending at the prior visit were each associated with abstinence on the trial, HR = 1.12 [1.03: 1.22] and HR = 1.32 [1.08: 1.61], respectively. Controlling for decision-making, spending, and cumulative abstinence, prior abstinence remained the largest predictor of future abstinence, HR = 3.85 [2.88: 5.16]. Decision-making tendencies and spending are correlated yet independently associated with abstinence reinforcement in CM. Findings highlight the opportunity for behavioral treatment programs to tailor program structures to individual-specific characteristics. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Decision-Making by Patients With Methamphetamine Use Disorder Receiving Contingency Management Treatment: Magnitude and Frequency Effects.

BackgroundIndividuals with substance use disorders exhibit maladaptive decision-making on the Iowa Gambling Task (IGT), which involves selecting from card decks differing in the magnitudes of rewards, and the frequency and magnitude of losses. We investigated whether baseline IGT performance could predict responses to contingency management (CM) by treatment-seeking individuals with methamphetamine use disorder (MA Use Disorder) in Cape Town, South Africa.MethodsTwenty-nine individuals with MA Use Disorder underwent an 8-week, escalating reinforcement, voucher-based CM treatment in a study on the suitability of CM therapy for the South African context. Along with 20 healthy control participants, they performed a computerized version of the IGT before starting CM treatment. Seventeen participants maintained abstinence from methamphetamine throughout the trial (full responders), and 12 had an incomplete response (partial responders). Performance on the IGT was scored for magnitude effect (selection of large immediate rewards with high long-term loss) and for frequency effect (preference for frequent rewards and avoidance of frequent losses). Group differences were investigated using linear mixed-effect modeling.ResultsPartial responders made more selections from decks providing large, immediate rewards and long-term losses than healthy controls [p = 0.038, g = -0.77 (-1.09: -0.44)]. Full responders showed a greater, nonsignificant preference for frequent rewards and aversion to frequent losses than partial responders [p = 0.054, g = -0.63 (-0.95: -0.29)].ConclusionsA predilection for choices based on the size and immediacy of reward may reflect a cognitive strategy that works against CM. Pretesting with a decision-making task, such as the IGT, may help in matching cognitive therapies to clients with MA Use Disorder.

Voucher-Based Contingency Management is Efficacious but Underutilized in Treating Addictions.

The United States lags far behind other industrialized countries on major markers of population health. Population health experts identify unhealthy behavior patterns (e.g., cigarette smoking, other substance use disorders, physical inactivity and poor food choices, nonadherence with recommended medical regimens) as the largest contributor to the status quo. Because these risk behaviors are overrepresented in socioeconomically disadvantaged and other vulnerable populations, they also increase health disparities. Hence, identifying evidence-based strategies to promote and sustain health-related behavior change is critical to improving U.S. population health. In this report, we review research demonstrating the efficacy of voucher-based contingency management delivered alone or in combination with other interventions for treating substance use disorders and other health-related behavior problems. The efficacy supporting these interventions is robust and discernible at the level of controlled randomized clinical trials and meta-analyses. Unfortunately, these evidence-based interventions are being underutilized in routine clinical care for substance use disorders, although they are used broadly in private-sector wellness programs and international programs to reduce chronic poverty. This report reviews the evidence supporting the efficacy of voucher-based contingency management using projects developed at the University of Vermont as exemplars and discusses dissemination of the model to public and private sector efforts to improve individual and population health.

Accounting for the uncounted: Physical and affective distress in individuals dropping out of oral naltrexone treatment for opioid use disorder

BackgroundThe theoretical benefits of naltrexone as a treatment for opioid use disorder (e.g., safety, non-addictive, low risk of diversion) stand in sharp contrast to its disappointing record on retention in most samples. The relationship of uncomfortable physical and dysphoric symptoms to retention on naltrexone is a controversial and under-studied issue. MethodsUsing data from a randomized controlled trial of voucher-based contingency management and support from a significant other to enhance retention on oral naltrexone, we compared self-reported somatic and dysphoric symptoms, measured weekly, for individuals who were retained on naltrexone through the 12-week trial (n = 50) versus those who dropped out (n = 70). ResultsThere were no differences between participants who completed treatment and those who dropped out on multiple baseline characteristics, including somatic or affective symptoms prior to treatment. However, whether analyzed cross-sectionally or over time, participants who dropped out consistently reported higher rates of somatic symptoms, particularly difficulty sleeping, as well as affective symptoms, including multiple indicators of depression, anxiety, and anhedonia. ConclusionsAlthough the smaller group of participants who were retained on oral naltrexone for 12 weeks reported decreasing physical and affective discomfort over time, there was substantial evidence that those who dropped out experienced continued and significant levels of distress. Individuals who report physical or affective distress while taking naltrexone may be at higher risk of dropout.

Income Levels and Response to Contingency Management for Smoking Cessation

ABSTRACTBackground: Contingency management (CM) has demonstrated its efficacy in treating many drug addictions, including nicotine. However, one of the most commonly perceived limitations with regard to its dissemination into community settings is whether this protocol could be equally effective for treating patients across different income levels. Objective: This study aimed to examine whether individuals' income levels affect treatment success in a cognitive behavioral treatment (CBT) that included a voucher-based CM protocol for smoking cessation. Methods: A total of 92 treatment-seeking smokers in a community setting were randomly assigned to a CBT group (N = 49) or to a CBT plus CM group (N = 43). The CM procedure included a voucher program through which smoking abstinence was reinforced on a schedule of escalating magnitude of reinforcement with a reset contingency. We analyzed the impact of self-reported monthly income, alone and in combination with treatment condition, on short-term (treatment retention) and long-term (self-reported number of days of continuous smoking abstinence at 6-month follow-up) results. Results: Income had no effect on treatment retention and continuous abstinence outcomes at 6-month follow-up in either treatment condition. Treatment modality emerged as the only significant predictor of treatment success. Conclusions: Our findings suggest that treatment-seeking smokers from the general population respond equally well to CM regardless of their income levels. The results of this randomized controlled trial support the generalizability of this evidenced-based program into community settings.

Contingent Vs. Non-Contingent Rewards: Time-Based Intervention Response Patterns Among Stimulant-Using Men Who Have Sex With Men

Stimulant use rates are higher among men who have sex with men (MSM) than the general population. Contingency management (CM) may be an effective intervention for reducing stimulant use in this population. To specify both the mechanism and temporal effects of contingent reward on behavior change, logistic growth trajectory modeling (LGTM) was used to contrast a non-contingent matched rewards condition (i.e., non-contingent yoked controls; NCYC) to a voucher-based CM intervention (maximum=$430) to reduce stimulant use among MSM. Stimulant-using MSM were randomized to either a CM intervention (n=70) or a NCYC condition (n=70). Results from a LGTM (analytical sample n=119; nCM=61; nNCYC=58) indicated four distinct intervention response patterns: responders (i.e., predicted >90% stimulant metabolite-free urinalyses; 64.7% of sample); worsening intervention response (14.3%); non-responders (12.6%); and, single-positive (8.4%); all estimated trajectory coefficients were significant at p<0.03 (2-tailed). Participants receiving CM were significantly overrepresented in the responder (64%) and single-positive (80%) categories (χ2(3)=29.04; p<0.001); all non-responders and 76.5% of the worsening intervention response category were in the NCYC condition. Results demonstrate the utility of trajectory modeling and further support the contingent application of reward as the operative mechanism associated with patterns of stimulant abstinence with CM applied to a sample of stimulant-using MSM outside the context of formal drug treatment.

Anhedonia Is Associated with Poorer Outcomes in Contingency Management for Cocaine Use Disorder

This study explored anhedonia (lack of interest or pleasure in non-drug rewards) as a potentially modifiable individual difference associated with the effectiveness of Contingency Management (CM). It also tested the hypothesis that a dopaminergic drug, levodopa (L-DOPA), would improve the effectiveness of CM, particularly in individuals high in anhedonia. The study was a single-site, randomized, double-blind, parallel group, 12-week trial comparing L-DOPA with placebo, with both medication groups receiving voucher-based CM targeting cocaine-negative urines. Participants were N=85 treatment-seeking adults with CUD. Anhedonia was measured at baseline using a validated self-report measure and a progressive ratio behavioral measure. Treatment Effectiveness Score (TES) was defined as the total number of cocaine-negative urines submitted. Analyses based on Frequentist general linear models were not significant, but Bayesian analyses indicated a high probability (92.6%) that self-reported anhedonia was associated with poor treatment outcomes (lower TES). L-DOPA did not significantly improve outcomes, nor was the effect of L-DOPA moderated by anhedonia. While the study failed to replicate positive findings from previous studies of L-DOPA in combination with CM, it does provide preliminary evidence that anhedonia may be a modifiable individual difference associated with poorer CM outcomes.

A contingency management method for 30-days abstinence in non-treatment seeking young adult cannabis users

BackgroundRates of young adult cannabis use are rising, perceived harm is at its historical nadir, and most users do not want to quit. Most studies evaluating effects of cannabis use in young adults are cross-sectional, limiting causal inference. A method to reliably induce abstinence periods in cannabis users would allow assessment of the effects of abstinence and resumption of use on a variety of outcomes in a within-subjects, repeated measures design. MethodsWe examined the efficacy and feasibility of a voucher-based contingency management procedure for incentivizing one month of continuous cannabis abstinence among young adults who reported at least weekly cannabis use, volunteered to participate in a laboratory study, and did not express a desire to discontinue cannabis use long-term. Continuous cannabis abstinence was reinforced with an escalating incentive schedule, and self-report of abstinence was confirmed by frequent quantitative assays of urine cannabis metabolite (THCCOOH) concentration. New cannabis use during the abstinence period was determined using an established algorithm of change in creatinine-adjusted cannabis metabolite concentrations between study visits. ResultsThirty-eight young adults, aged 18–25 years, enrolled and 34 (89.5%) attained biochemically confirmed 30-day abstinence. Among those who attained abstinence, 93.9% resumed regular use within two-weeks of incentive discontinuation. ConclusionFindings support the feasibility and efficacy of contingency management to elicit short-term, continuous cannabis abstinence among young adult, non-treatment seeking, regular cannabis users. Further work should test the effectiveness of this contingency management procedure for cannabis abstinence in periods longer than one month, which may be required to evaluate some effects of abstinence.

A review of the literature on contingency management in the treatment of substance use disorders, 2009–2014

This report describes a systematic literature review of voucher and related monetary-based contingency management (CM) interventions for substance use disorders (SUDs) over 5.2years (November 2009 through December 2014). Reports were identified using the search engine PubMed, expert consultations, and published bibliographies. For inclusion, reports had to (a) involve monetary-based CM; (b) appear in a peer-reviewed journal; (c) include an experimental comparison condition; (d) describe an original study; (e) assess efficacy using inferential statistics; (f) use a research design allowing treatment effects to be attributed to CM. Sixty-nine reports met inclusion criteria and were categorized into 7 research trends: (1) extending CM to special populations, (2) parametric studies, (3) extending CM to community clinics, (4) combining CM with pharmacotherapies, (5) incorporating technology into CM, (6) investigating longer-term outcomes, (7) using CM as a research tool. The vast majority (59/69, 86%) of studies reported significant (p<0.05) during-treatment effects. Twenty-eight (28/59, 47%) of those studies included at least one follow-up visit after CM was discontinued, with eight (8/28, 29%) reporting significant (p<0.05) effects. Average effect size (Cohen's d) during treatment was 0.62 (95% CI: 0.54, 0.70) and post-treatment it was 0.26 (95% CI: 0.11, 0.41). Overall, the literature on voucher-based CM over the past 5years documents sustained growth, high treatment efficacy, moderate to large effect sizes during treatment that weaken but remain evident following treatment termination, and breadth across a diverse set of SUDs, populations, and settings consistent with and extending results from prior reviews.

Cost-effectiveness of a voucher-based intervention for smoking cessation

ABSTRACTBackground: Contingency management (CM) has been shown to be effective in reducing smoking consumption, but has traditionally been criticized for its costs. Objectives: This study assessed the cost-effectiveness of using a voucher-based CM protocol added to a cognitive behavioral treatment (CBT) for smoking cessation among treatment-seeking patients from the general population. Methods: A total of 92 patients were randomly assigned to CBT or CBT plus CM for abstinence. Incremental cost-effectiveness ratios (ICERs) were calculated by dividing the increase in costs by the increase in effects (continuous abstinence, longest duration of abstinence at 6-month follow-up and cotinine results during the treatment). An acceptability curve illustrated the statistical uncertainty surrounding the cost-effectiveness estimate. We also determined the optimum cost per participant for predicting the smoking status at 6-month follow-up. Results: The average cost per participant in the CBT condition was €138.73 (US$ 150.23) as opposed to €411.61 (US$ 445.73) in the CBT plus CM condition (p < 0.01). The incremental cost of using voucher-based CM to increase the number of participants that maintained abstinence at 6-month follow-up by one extra participant was €68.22 (US$ 73.88), and to lengthen the longest duration of abstinence by 1 week was €53.92 (US$ 58.39). The incremental cost to obtain an extra cotinine-negative result was €181.90 (US$ 196.98). Conclusion: Compared with CBT alone, the voucher-based protocol required additional costs but achieved significantly better outcomes. These results will allow stakeholders to make policy decisions about CM implementation for smoking cessation in the broader community.

Contingency management for substance use disorders in Spain: Implications for research and practice

ObjectiveWe provide a narrative review of published studies evaluating voucher-based contingency management (CM) treatment for cocaine, nicotine and cannabis use disorders in Spain and discuss the concerns and future challenges. MethodPublished studies between 2008 and 2015 that evaluated the impact of incentives for SUD in Spain and included an appropriate control or comparison condition were identified and reviewed. ResultsAdding voucher-based CM to standard treatments obtained better treatment retention and cocaine abstinence than standard care alone. CM also improved psychosocial functioning. Economic status or depressive symptoms did not affect the results of CM treatment for cocaine dependence. The addition of a CM protocol to cognitive behavioral treatment (CBT) also improved treatment effectiveness for smoking cessation. Available data on the effect of CM on cannabis use disorders (CUD) with young people did not allow confirmation of its superiority to date. ConclusionThe research conducted to date in Spain confirms and expands the findings of studies conducted in the US supporting the effectiveness of CM in the context of community settings with cocaine- and nicotine-dependents. However, CM has not yet been readily adopted into general clinical practice in Spain or the rest of Europe. The limited effectiveness of CM for CUD is likely due to the scarcity of data and may change with more studies, taking into account recent research on this topic in the US. Continued efforts are warranted to further develop and disseminate incentive-based treatments for SUD across clinical settings and populations in Spain.

Voucher-based contingency management and in-treatment behaviors in smoking cessation treatment

A high percentage of patients relapse within months following an attempt to quit smoking. For this reason, greater understanding of the determinants of successful smoking cessation is needed. The present study assessed the effect of Contingency Management (CM) combined with Cognitive-Behavioral Treatment (CBT) on certain in-treatment behaviors (treatment retention, in-treatment smoking abstinence, and weekly decrease of cotinine levels) and examined the effects of these in-treatment behaviors on smoking status at a 6-month follow-up. A total of 154 treatment-seeking patients in a community setting were randomly assigned to a CBT, CBT plus CM for Abstinence (CMA) or to a CBT plus CM for Shaping cessation (CMS) group. Both CBT+CM procedures improved the in-treatment behaviors compared to CBT alone. These in-treatment behaviors (particularly in-treatment smoking abstinence) were associated with long-term abstinence. The effect of CM on in-treatment behaviors may partially explain the positive long-term outcomes of this procedure. Our findings extend previous knowledge about the effect of CM on smoking behavior.

Changes in cigarette and alcohol use during cannabis abstinence

Rates of young adult cannabis use are rising, perceived harm is at its historical nadir, and most users do not want to quit. Most studies evaluating effects of cannabis use in young adults are cross-sectional, limiting causal inference. A method to reliably induce abstinence periods in cannabis users would allow assessment of the effects of abstinence and resumption of use on a variety of outcomes in a within-subjects, repeated measures design.We examined the efficacy and feasibility of a voucher-based contingency management procedure for incentivizing one month of continuous cannabis abstinence among young adults who reported at least weekly cannabis use, volunteered to participate in a laboratory study, and did not express a desire to discontinue cannabis use long-term. Continuous cannabis abstinence was reinforced with an escalating incentive schedule, and self-report of abstinence was confirmed by frequent quantitative assays of urine cannabis metabolite (THCCOOH) concentration. New cannabis use during the abstinence period was determined using an established algorithm of change in creatinine-adjusted cannabis metabolite concentrations between study visits.Thirty-eight young adults, aged 18–25 years, enrolled and 34 (89.5%) attained biochemically confirmed 30-day abstinence. Among those who attained abstinence, 93.9% resumed regular use within two-weeks of incentive discontinuation.Findings support the feasibility and efficacy of contingency management to elicit short-term, continuous cannabis abstinence among young adult, non-treatment seeking, regular cannabis users. Further work should test the effectiveness of this contingency management procedure for cannabis abstinence in periods longer than one month, which may be required to evaluate some effects of abstinence.

Contingency management voucher redemption as an indicator of delayed gratification

This prospective analysis tested whether frequency of voucher redemptions during a contingency management (CM) substance use intervention was significantly associated with participants' ongoing substance use. Homeless, substance-dependent men who have sex with men (N=131) were randomized into either a “full” or “lite” voucher-based CM intervention. All participants earned vouchers for attendance and participation; participants in the CM-full condition also received vouchers for substance abstinence and enactment of prosocial and/or health-promoting behaviors. Multivariate longitudinal negative binomial regression analyses (n=118) assessed the association between substance use during the intervention and frequency of voucher redemptions. Participants who used methamphetamine (IRR=0.66; 95% CI=0.44–0.99) and/or opiates (IRR=0.60; 95% CI=0.40–0.99) during the intervention exhibited less time between voucher redemptions than individuals who achieved abstinence from these substances. Voucher redemption logs can be cost-effective and unobtrusive tools for measuring study participants' tendency to delay gratification.

Contingency Management Reduces Symptoms of Psychological and Emotional Distress among Homeless, Substance-dependent Men Who Have Sex with Men.

This prospective analysis evaluated the efficacy of a contingency management (CM) intervention to improve the psychological health of non-treatment seeking, homeless, substance-dependent, men who have sex with men in Los Angeles. It was hypothesized that administration of CM would be associated with reductions in participants' symptoms of psychological and emotional distress. One hundred and thirty-one participants were randomized into either a voucher-based contingency management (CM; n = 64) condition reinforcing substance abstinence and prosocial/health-promoting behaviors, or to a control condition (n = 67). Participants' symptoms of psychological and emotional distress were assessed at intake and at 12-months post-randomization. Participants randomized into the CM intervention exhibited significantly lower levels of psychological distress in all measured symptom domains up to one year post randomization, reductions not evidenced in the control arm. Omnibus tests resultant from seemingly unrelated regression analysis confirmed that CM was significantly associated with reductions in symptoms of psychological and emotional distress, even when controlling for biomarker-confirmed substance use outcomes (χ2(9) = 17.26; p < 0.05). Findings demonstrate that a CM intervention reduced symptoms of psychological and emotional distress among a sample of non-treatment seeking, homeless, substance-dependent men who have sex with men.

Contingency Management for Patients With Serious Mental Illness and Stimulant Dependence

Contingency Management for Patients With Serious Mental Illness and Stimulant Dependence

Delay discounting is associated with treatment response among cocaine-dependent outpatients.

Delay discounting (DD) describes the rate at which reinforcers lose value as the temporal delay to their receipt increases. Steeper discounting has been positively associated with vulnerability to substance use disorders, including cocaine use disorders. In the present study, we examined whether DD of hypothetical monetary reinforcers is associated with the duration of cocaine abstinence achieved among cocaine-dependent outpatients. Participants were 36 adults who were participating in a randomized controlled trial examining the efficacy of voucher-based contingency management (CM) using low-magnitude (N = 18) or high-magnitude (N = 18) voucher monetary values. DD was associated with the number of continuous weeks of cocaine abstinence achieved, even after adjusting for treatment condition during the initial 12-week, t(33) = 2.48, p = .045 and entire recommended 24-week of treatment, t(33) = 2.40, p = .022. Participants who exhibited steeper discounting functions achieved shorter periods of abstinence in the Low-magnitude voucher condition (12-week: t(16) = 2.48, p = .025; 24-week: t(16) = 2.68, p = .017), but not in the High-magnitude voucher condition (12-week: t(16) = 0.51, p = .618; 24-week: t(16) = 1.08, p = .298), although the interaction between DD and treatment condition was not significant (12-week: t(32) = -1.12, p = .271; 24-week: t(32) = -0.37, p = .712). These results provide further evidence on associations between DD and treatment response and extend those observations to a new clinical population (i.e., cocaine-dependent outpatients), while also suggesting that a more intensive intervention like the High-magnitude CM condition may diminish this negative relationship between DD and treatment response.

Effects of smoking cessation with voucher‐based contingency management on birth outcomes

This study examined whether smoking cessation using voucher-based contingency management (CM) improves birth outcomes. Data were combined from three controlled trials. Each of the trials was conducted in the same research clinic devoted to smoking and pregnancy. Participants (n=166) were pregnant women who participated in trials examining the efficacy of voucher-based CM for smoking cessation. Women were assigned to either a contingent condition, wherein they earned vouchers exchangeable for retail items by abstaining from smoking, or to a non-contingent condition where they received vouchers independent of smoking status. Birth outcomes were determined by review of hospital delivery records. Antepartum abstinence was greater in the contingent than non-contingent condition, with late-pregnancy abstinence being 34.1% versus 7.4% (P<0.001). Mean birth weight of infants born to mothers treated in the contingent condition was greater than infants born to mothers treated in the non-contingent condition (3295.6 ± 63.8 g versus 3093.6 ± 67.0 g, P = 0.03) and the percentage of low birth weight (<2500 g) deliveries was less (5.9% versus 18.5%, P = 0.02). No significant treatment effects were observed across three other outcomes investigated, although each was in the direction of improved outcomes in the contingent versus the non-contingent condition: mean gestational age (39.1 ± 0.2 weeks versus 38.5 ± 0.3 weeks, P = 0.06), percentage of preterm deliveries (5.9 versus 13.6, P = 0.09), and percentage of admissions to the neonatal intensive care unit (4.7% versus 13.8%, P = 0.06). These results provide evidence that smoking-cessation treatment with voucher-based CM may improve important birth outcomes.

The cost-effectiveness of prize-based and voucher-based contingency management in a population of cocaine- or opioid-dependent outpatients

Objective To evaluate the cost-effectiveness of using prize-based and voucher-based contingency management (CM) as additions to standard treatment for cocaine- or heroin-dependent outpatients in community treatment centers. Methods This cost-effectiveness analysis is based on a randomized clinical trial conducted at three community-based outpatient psychosocial substance abuse treatment clinics. A total of 142 cocaine- or heroin-dependent outpatients were randomly assigned to one of three treatment conditions: standard treatment (ST), ST with prizes (prize CM), or ST with vouchers (voucher CM) for 12 weeks. The primary patient outcome was the longest duration of confirmed abstinence (LDA) from cocaine, opioids and alcohol during treatment. Unit costs were collected from the three participating clinics. Resource utilizations and patient outcomes were obtained from the clinical trial. Incremental cost-effectiveness ratios (ICERs) and acceptability curves were used to evaluate the relative cost-effectiveness of the interventions. Results Based on the ICERs and acceptability curves, ST is likely to be the most cost-effective intervention when the threshold value to decision makers of lengthening the LDA during treatment by 1 week is less than approximately $166, and prize CM is likely to be the most cost-effective intervention when the threshold value is greater than approximately $166. Conclusions Prize CM was found likely to be the most cost-effective intervention over a comparatively wide range of threshold values for lengthening the LDA during treatment by 1 week. However, additional studies with alternative incentive parameters are required to determine the generalizability of our results.

VOUCHER‐BASED CONTINGENT REINFORCEMENT OF SMOKING ABSTINENCE AMONG METHADONE‐MAINTAINED PATIENTS: A PILOT STUDY

This study evaluated the efficacy of a contingency management (CM) intervention to promote smoking cessation in methadone-maintained patients. Twenty participants, randomized into contingent (n=10) or noncontingent (n=10) experimental conditions, completed the 14-day study. Abstinence was determined using breath carbon monoxide and urine cotinine levels. Contingent participants received voucher-based incentives for biochemical evidence of smoking abstinence. Noncontingent participants earned vouchers independent of smoking status. Contingent participants achieved significantly more smoking abstinence and longer durations of continuous smoking abstinence than did noncontingent participants. These results support the potential efficacy of using voucher-based CM to promote smoking cessation among methadone-maintained patients.