Income does not affect response to contingency management treatments among community substance abuse treatment-seekers

The present study examined a commonly held belief that contingency management (CM) may be less effective for substance abusers with relatively more economic resources compared to those with relatively few resources. Using a combined sample of 393 treatment-seeking cocaine abusers from three clinical trials involving randomization to standard care or standard care plus CM conditions, we assessed the impact of past year income, alone and in combination with treatment condition, as well as income type (i.e., earned, illegal, unstable) on the longest duration of continuous verified abstinence (LDA) achieved during treatment. Results suggested that income had no effect on LDA in either condition, and that CM's effectiveness did not deteriorate among those with better economic resources in the present sample. This finding may be of value to clinicians and administrators who are considering the addition of CM to standard care treatments in community outpatient substance abuse clinics and have concerns about the generalizability of CM across clients with various economic resources.