Contingency management for treatment attendance: A meta-analysis

Abstract Background Treatment providers have applied contingency management (CM) treatment, an intervention that often rewards individuals for drug abstinence (i.e., ABS CM), to treatment engagement as well. However, we know little about the magnitude of treatment effects when providers target attendance behaviors (i.e., ATT CM). Methods This study conducted a systematic search to identify studies that included ATT CM, either in isolation or in combination with ABS CM. The study used meta-analysis to estimate the effect size of ATT CM and ABS CM + ATT CM on treatment attendance and drug abstinence. We identified a total of 10 studies including 12 CM treatments (6 ATT CM and 6 ABS CM + ATT CM) with 1841 participants. Results Results indicated a moderate effect (d = 0.47, 95% confidence interval (CI) [0.25, 0.69]) of ATT CM on attendance relative to non–reward active comparison conditions. Frequency of rewards was significantly associated with larger effect sizes. Results also indicated a small effect (d = 0.22, 95% CI [0.12, 0.33]) of ATT CM on abstinence outcomes relative to nonreward comparisons, p   0.05). Conclusion Overall, the results supported ATT CM for increasing treatment engagement, with smaller effects on abstinence. Effects on abstinence were smaller than those observed in prior meta-analyses focused on ABS CM. No significant differences existed in attendance or abstinence outcomes between ATT CM and ABS + ATT CM. However, future studies are needed to experimentally compare ABS CM + ATT CM to ABS CM, and ATT CM to determine additive effects. Clinics implementing CM should consider the differential effects between ATT CM and ABS CM when selecting target behavior(s).