Absence of conflict of interest.
Drebing, C. E., Van Ormer, E. A., Mueller, L., Hebert, M., Penk, W. E., Petry, N. M., . . . Rounsaville, B. (2007). Adding contingency management intervention to vocational rehabilitation: Outcomes for dually diagnosed veterans. Journal of Rehabilitation Research & Development, 44(6), 851-865.
- The study examined the impact of contingency management (CM) on employment and health outcomes.
- The authors conducted a randomized controlled trial, using a work history form and drug and alcohol screenings to collect participant data.
- At nine months, 50 percent of the individuals in the treatment group had obtained competitive employment compared with only 28 percent of those in the control group. Treatment group participants remained abstinent from drugs and alcohol longer than control group participants (11.8 weeks versus 9.4 weeks). Treatment group participants were also less likely to relapse by week 16 (50 percent versus 72 percent).
- The quality of causal evidence presented in this report is high for employment outcomes because it was based on a well-implemented randomized controlled trial. This means we are confident that the estimated effects are attributable to the CM program, and not to other factors.
Features of the Intervention
Contingency management (CM) participants received incentives for taking steps toward obtaining and maintaining employment and abstaining from substance use. Incentives were in the form of cash or a voucher for cash that participants could immediately redeem at the hospital cashier.
Employment incentives were offered in two phases: During Phase I (the first 16 weeks), incentives were offered for completing work-related activities, such as searching or applying for jobs. Veterans were rewarded if they had completed various work-related activities for which they could earn up to $610. Offered for the first 32 weeks, Phase II aimed to incentivize obtaining and maintaining employment. For the entire 36-week course of the intervention, veterans could earn up to $1,170.
Veterans could also receive incentives for abstaining from substance use. Treatment group participants were screened for drug and alcohol use twice a week over a 16-week period and received $2.50 for an initial clean drug and alcohol screening. The value of each consecutive negative screen increased by $1, totaling $560 if all 32 samples tested clean. Treatment group participants with positive screens received no payment, and any future possible incentives were reset to the original $2.50 level. Control group participants received $5 per biweekly screen for a total of $160 over 16 weeks, regardless of test results.
The program was implemented at the Veterans Affairs Medical Center in Bedford, Massachusetts, in 2007. To be eligible for the program, veterans had to meet the Diagnostic and Statistical Manual of Mental Disorders, fourth edition, criteria for dual diagnosis of a psychiatric (schizophrenia, bipolar disorder, major depression, posttraumatic stress disorder, or other anxiety disorder) and substance abuse disorder for alcohol, cocaine, or opiates. Other requirements for participants included having the potential for returning to competitive supported employment within 6 months, not having had any suicidal or homicidal ideations within the past 12 weeks, remaining abstinent from drugs and alcohol for at least 1 week, being age 55 or younger, having no medical problems that would hinder their ability to obtain competitive employment, participating in vocational rehabilitation (VR) services within the Compensated Work Therapy (CWT) program for at least 4 months, living within the local region for 12 months, having at least 10 years of formal education, and having no history of significant head trauma or other disorder causing significant cognitive impairment. The majority of the sample members were white, middle-aged men with more than 12 years of education. Most had affective or anxiety disorders, and all met the criteria for dependence on either alcohol, cocaine, or opiates.
Features of the Study
The authors conducted a randomized controlled trial, analyzing data on a total of 100 veterans. Some veterans were assigned to receive the CM intervention (the treatment group) in addition to traditional VR services, and other veterans were assigned to receive only traditional VR services.
Veterans receiving VR services (both the treatment and control groups) were placed in structured work settings and were compensated with an average of $7.28 per hour. While working, staff helped veterans resolve on-the-job difficulties and prepared them to obtain their own competitive job. Staff also encouraged veterans to perform job-search tasks, abstain from drugs and alcohol, and seek competitive employment.
The authors used a baseline evaluation to collect baseline data. To assess the intervention’s impacts on employment and health outcomes, the authors used the Job Search Behaviors Index, along with drug and alcohol screenings. Data were collected regularly for the first 16 weeks after participants were randomly assigned to a study group, with follow-up data collection occurring at 3, 6, and 9 months. To encourage data collection, the control group veterans received $5 per biweekly screening over 16 weeks, regardless of the test results, for a total of $160. Control group participants received an additional $30 incentive for completing their final interview, compared to treatment group participants.
- At nine months, 50 percent of treatment group participants had obtained competitive employment compared to only 28 percent of control group participants.
- Participants in the treatment group completed 39 percent more job-search tasks than control group participants.
- At the end of the 16-week period, 86 percent of treatment group participants had completed their resumes compared to 68 percent of control group participants.
- Seventy-eight percent of the treatment group had submitted at least one job application by week 16 compared to 50 percent of the control group.
- Treatment group participants remained abstinent from drugs and alcohol longer than control group participants (11.8 weeks versus 9.4 weeks).
- Treatment group participants were less likely to relapse by week 16 (50 percent versus 72 percent), but in the full nine-month follow-up period, the difference between the groups was no longer statistically significant.
Causal Evidence Rating
The quality of causal evidence presented in this report is high for employment outcomes because it was based on a well-implemented randomized controlled trial. This means we are confident that the estimated effects are attributable to the CM program, and not to other factors.