Contingency Management of Psychostimulant Abuse in the Severely Mentally Ill

This study will evaluate the efficacy of a twelve week contingency management (CM) intervention for treating psycho-stimulant substance abuse when delivered in the context of a community mental health center (CMHC) setting for adults suffering from serious mental illness (SMI). The CM paradigm to be used is one which has been shown effective in several recent large clinical trials, using the variable magnitude of reinforcement procedure. The reinforcers will be vouchers or actual items useful for day to day living in this population. Two hundred SMI participants with co-occurring stimulant disorders will be recruited from a large urban CMHC and randomized to receive either the active CM paradigm plus treatment as usual (TAU), or TAU which will include the delivery of reinforcement for study involvement (reinforcement that is not contingent on drug abstinence). The primary outcome is change in psycho-stimulant use (methamphetamine, amphetamine and/or cocaine). Secondary outcomes include: changes in use of other illegal drugs or alcohol; changes in CMHC treatment adherence and follow-through; changes in psychiatric symptoms, quality of life, and community outcomes (homelessness, incarcerations, etc.). Additional outcomes to be measured include changes in drug craving, stage of change, nicotine use, and HIV risk status. The study involves two phases, the 12 week treatment phase, where CM and control treatments are delivered, as well as a 3 month follow up phase.