Randomized trial of prize-based reinforcement density for simultaneous abstinence from cocaine and heroin.

Abstract

To examine the effect of reinforcer density in prize-based abstinence reinforcement, heroin/cocaine users (N = 116) in methadone maintenance (100 mg/day) were randomly assigned to a noncontingent control group (NonC) or to 1 of 3 groups that earned prize draws for abstinence: manual drawing with standard prize density (MS) or computerized drawing with standard (CS) or high (CH) density. Probabilities (prizes/draw) were standard (50%) and high (78%); prize density was double blind. Mean prize values were CH, $286; CS, $167; MS, $139; and NonC, $171. Outcomes were % opioid/ cocaine-negative urines during the 12-week intervention and then 8 weeks postintervention as well as diagnosis of dependence up to 6 months poststudy. CH had significantly more negative specimens than did NonC during intervention and had more than all groups during postintervention treatment: Mean % negative (95% confidence interval) during postintervention treatment adjusted for baseline drug use and dropout were CH, 55% (14%-90%); CS, 7% (1%-27%); MS, 4% (1%-12%); and NonC, 3% (1%-10%). Current cocaine dependence diagnoses after treatment were significantly lower in contingent compared with noncontingent groups. Computerized drawing with higherdensity prizes enhanced reduction of cocaine use; abstinence reinforcement had long-term therapeutic benefits. Keywords contingency management; opiate; cocaine dependence; opiate dependence; methadone maintenance One of the most robust means of inducing behavioral change in patients with heroin and cocaine dependence is a set of behavioral techniques called contingency management (CM;Higgins et al., 1991;Higgins & Silverman, 1999). An especially powerful component of CM is a voucherbased escalating-reinforcement schedule developed by Higgins et al. (1991), in which reinforcement increases with each consecutive drug-negative urine sample. This procedure has repeatedly been shown effective in the treatment of cocaine abuse and dependence, with or without concurrent dependence on heroin (Higgins et al., 1991;Silverman et al., 1996). Compared with a control procedure in which equivalent values of vouchers are given independent of cocaine use, the escalating-reinforcement procedure reduces the frequency of cocaine use, increases the mean duration of abstinence, reduces patients' ratings of their desire for cocaine, and increases the frequency with which abstainers report engaging in coping behaviors .Correspondence concerning this article should be addressed to Udi E. Ghitza, Clinical Pharmacology and Therapeutics Branch, Treatment Section, IRP, NIDA, NIH, 5500 Nathan Shock Drive, Baltimore, MD 21224. E-mail: ghitzau@intra.nida.nih.gov. NIH Public Access NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author ManuscriptThe voucher reinforcers used in the escalating-reinforcement procedure are certificates presented immediately on provision of a drug-negative urine sample; monetary values indicated on the certificates accrue and are redeemable later for a variety of goods and services. The use...

Randomized Trial Comparing Two Treatment Strategies Using Prize‐based Reinforcement of Abstinence in Cocaine and Opiate Users

“…Finally, although the present study design allowed a comparison between the two CM strategies and against drug use early in treatment, the inclusion of a noncontingent control group would have provided additional comparative information on the overall effect sizes of the CM interventions. A noncontingent group in the larger clinical trial (Ghitza et al, 2007) that we conducted immediately after this pilot study appeared to show less abstinence than was seen here, though of course the groups cannot be directly compared.…”

A randomized trial of contingency management delivered by community therapists.

“…Some (e.g., Ghitza et al, 2007; Petry & Martin, 2002; Petry, Martin, & Simcic, 2005), but not all (e.g., Petry et al, 2007; Rawson et al, 2002; Silverman et al, 1999), studies of CM in methadone clinics found significant benefits of CM on abstinence after CM ended. This study found a trend for SC patients to submit more negative samples at follow-up than CM patients.…”

Self-report of illicit benzodiazepine use on the Addiction Severity Index predicts treatment outcome

“…They have been shown to be important indicators of treatment success (Sorensen and Copeland, 2000;Teichner et al, 2001;Hudson et al, 2002;Kampman et al, 2004). To have adequate statistical power, we combined data from two of our clinical trials evaluating the efficacy of CM for heroin/cocaine abuse Ghitza et al, 2007Ghitza et al, , 2008. Each participant was enrolled in only one of the clinical trials.…”