Contingent reinforcement increases cocaine abstinence during outpatient treatment and 1 year of follow-up.

This study assessed whether contingent incentives can be used to reinforce cocaine abstinence in dependent outpatients. Seventy cocaine-dependent outpatients were randomized into 2 conditions. All participants received 24 weeks of treatment and 1 year of follow-up. The treatment provided to all participants combined counseling based on the community reinforcement approach with incentives in the form of vouchers exchangeable for retail items. In 1 condition, incentives were delivered contingent on cocaine-free urinalysis results, whereas in the other condition incentives were delivered independent of urinalysis results. Abstinence-contingent incentives significantly increased cocaine abstinence during treatment and 1 year of follow-up compared with noncontingent incentives.