This study evaluated the efficacy of a low-cost, prize reinforcement contingency management (CM) intervention in community-based treatment centers for reducing cocaine use.
Cocaine-abusing out-patients (n=120) were assigned randomly to one of three 12-week conditions: standard treatment, standard treatment plus CM with an expected maximum of $80 of reinforcement or standard treatment plus CM with an expected maximum of $240 of reinforcement. In the CM conditions, patients earned the opportunity to win prizes for submitting negative urine samples and completing goal-related activities. Drug use was measured at intake and throughout a 3-month treatment period. Patients in the $240 CM condition achieved more abstinence than patients in the standard condition. Patients who initiated treatment with positive urinalysis results were most responsive to the CM intervention, with the $240 CM condition engendering the best effects in this subgroup. In contrast, patients who initiated treatment with negative urinalysis results generally remained abstinent during treatment, regardless of treatment assignment. On average, patients in the two CM conditions earned $36 and $68 in prizes. This study suggests that prize reinforcement CM may be suitable for community-based settings, and beneficial effects may be magnitude-dependent in more severe patients. (publisher abstract modified)