Contingent vouchers and motivational interviewing for cigarette smokers in residential substance abuse treatment

Abstract

Residential drug treatment provides an opportunity to intervene with smokers with substance use disorders (SUD). A randomized controlled clinical trial compared: (1) contingent vouchers (CV) for smoking abstinence to noncontingent vouchers (NCV), crossed with (2) motivational interviewing (MI) or brief advice (BA), for 184 smokers in SUD treatment. During the voucher period, 36% of carbon monoxide readings indicated smoking abstinence for those receiving CV versus 13% with NCV (p < .001). Post-treatment (3-9 months) point-prevalence abstinence rates were low (3-4% at each follow up), with more abstinence when CV was combined with MI (6.6% on average) than with BA (0% on average). No differential effects on drug use or motivation to quit smoking occurred. Thus, CV had limited effects on long-term smoking abstinence in this population but effects were improved when CV was combined with MI. More effective methods are needed to increase motivation to quit smoking and quit rates in this high-risk population.

Keywords: Brief advice; Contingency management; Contingent vouchers; Financial incentives; Motivation to quit smoking; Motivational interviewing; Nicotine dependence; Point-prevalence abstinence; Smoking cessation; Substance use disorders.

Figure 1

Flow chart of recruitment and retention.

Figure 2

Percent of participants confirmed abstinent from smoking at each follow-up period by assignment to Motivational Interviewing (MI) versus Brief Advice (BA) treatment and by CV (Contingent Vouchers) versus NCV (Noncontingent Vouchers) condition assignment. No main effects are significant. Standard errors are so small that standard error bars are not visible.