Exchanging Urine for Rewards

     Methamphetamine has been reported to be the leading substance reported among drug treatment episodes in California. One sub-population that has been recorded as using this type of drug is gay and bisexual men; reasons for this might be linked to having hepatitis, neurocognitive deficits, and/or cardiac effects. To help treat methamphetamine addictions, contingency management is used though using operant conditioning using reinforcements. Positive reinforcement is given when the individual, addicted to the substance, sustains from it.

    To better understand the success of contingency management, researchers wanted to test if substitutability and delay discounting were possible outcomes of contingency management for methamphetamine dependence. To conduct an experiment on this, 162 methamphetamine dependent gay and bisexual men, through voluntary informed consent, were chosen. These 162 men went through outpatient treatment. After a two week screening, the participants were then placed into four behavioral therapy conditions. When the individuals would provide a urine sample that tested negative for metabolites of meth, they were given a money voucher. For every sample that came back negative, the monetary amount would increase. If the participants produced three consecutive negative urine samples, they would be rewarded with a ten dollar bonus. These vouchers could then be redeemed for items or services that encouraged a prosocial lifestyle. Researchers measured this study through categorizing participants into spenders or savers, recording the purchases and the retailer, and made copies of bills that were paid through the vouchers given. Goods were categorized into used for entertainment or pleasure and utilitarian.

    Through this study, the researchers reported that, through contingency management, the participants showed significant reductions in using methamphetamine. Examination for the effects of spending and saving behaviors as a result of negative urine samples were not found. However, the study did show that those who were spenders tended to do better in treatment than those who saved. In researching the substitutability, results implied that replacing vouchers as rewards, instead of using meth, decreased the risk of a urine sample coming back positive. In regards to delay discounting, results suggested that those who saved were most likely to produce positive urine samples as opposed to those who spent.  

Abstract 

Murtaugh, K.L., Davis, A.L., Krishnamurti, T., Reback, C.J., & Shoptaw,S. (2013). Spend today, clean tomorrow: Predicting methamphetamine abstinence in a randomized controlled trial. American Psychological Association, 32(9), 958-966. doi: 10.1037/a0032922