Abstinence-contingent wage supplements to promote drug abstinence and employment: a randomised controlled trial

Abstract

Background: Poverty, unemployment and substance abuse are inter-related problems. This study evaluated the effectiveness of abstinence-contingent wage supplements in promoting drug abstinence and employment in unemployed adults in outpatient treatment for opioid use disorder.

Methods: A randomised controlled trial was conducted in Baltimore, MD, from 2014 to 2019. After a 3-month abstinence initiation and training period, participants (n=91) were randomly assigned to a usual care control group that received employment services or to an abstinence-contingent wage supplement group that received employment services plus abstinence-contingent wage supplements. All participants were invited to work with an employment specialist to seek employment in a community job for 12 months. Abstinence-contingent wage supplement participants could earn training stipends for working with the employment specialist and wage supplements for working in a community job, but had to provide opiate and cocaine-negative urine samples to maximise pay.

Results: Abstinence-contingent wage supplement participants provided significantly more opiate and cocaine-negative urine samples than usual care control participants (65% vs 45%; OR=2.29, 95% CI 1.22 to 4.30, p=0.01) during the 12-month intervention. Abstinence-contingent wage supplement participants were significantly more likely to have obtained employment (59% vs 28%; OR=3.88, 95% CI 1.60 to 9.41, p=0.004) and lived out of poverty (61% vs 30%; OR=3.77, 95% CI 1.57 to 9.04, p=0.004) by the end of the 12-month intervention than usual care control participants.

Conclusion: Abstinence-contingent wage supplements can promote drug abstinence and employment.

Trial registration number: ClinicalTrials.gov NCT02487745.

Keywords: employment; poverty; substance abuse; unemployment.

Conflict of interest statement

Competing interests: None declared.

© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.

Figures

Figure 1.

Flow of participants through the study.

Figure 2.

Percentage of opiate- and cocaine-negative urine samples for participants in the Usual Care Control group and the Abstinence-Contingent Wage Supplement group collapsed across the 12-month intervention (Phase 2). Dots show percentages for individual participants and the top of the shaded bar graphs show group means. Missing samples were considered positive. The difference between groups was statistically significant (OR=2.29, 95% CI=1.22-4.30, p =.01).

Figure 3.

Cumulative percentage of participants who were ever employed in the Usual Care Control group (circles) and the Abstinence-Contingent Wage Supplement group (squares) at intake (Int), during Phase 1 (P1), and across consecutive months during the intervention (Phase 2). Missing samples were coded as unemployed. The difference between groups at the end of Phase 2 was statistically significant (OR=3.88, 95% CI=1.60-9.41, p =.004).

Figure 4.

Cumulative percentage of participants who ever lived out of poverty in the Usual Care Control group (circles) and the Abstinence-Contingent Wage Supplement group (squares) at intake (Int), during Phase 1 (P1), and across consecutive months during the intervention (Phase 2). Missing samples were coded as living in poverty. The difference between groups at the end of Phase 2 was statistically significant (OR=3.77, 95% CI=1.57-9.04, p =.004).