Clinical trial NCT01040260: Low-Cost Contingency Management for Smoking Cessation
Official title: Low-Cost Contingency Management for Smoking Cessation
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Tobacco Use Cessation
Keywords: tobacco use disorder
Lead sponsor: University of California, San Francisco
Sponsor class: OTHER
First posted: 2009-12-29
Enrollment: 103
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: An innovative low-cost form of contingency management has been developed in which participants receive the chance to draw vouchers from a fish bowl depending on whether or not their abstinence from tobacco is confirmed by expired-air carbon monoxide. The vouchers can be redeemed for prizes of varying value. This form of contingency management has been shown to be effective in the treatment of a variety of substance use disorders, but has not been investigated in a clinical trial focusing on smoking cessation. Thus, the primary purpose of the proposed study will be to investigate the effects of a low-cost prize-based form of contingency management in the treatment of nicotine dependence. To accomplish this objective, we enrolled 103 current smokers into the study. The participants in Study Arm 1 received the contingency management intervention for 8 weeks, and the participants in Study Arm 2 had their smoking status assessed but did not receive the contingency management intervention. Both interventions received brief counseling and nicotine replacement therapy. The counseling was conducted in two 60-minute individual sessions scheduled one week apart with two follow-up phone calls at weeks 3, 4, and 6.

The primary outcome for this study was biochemically-validated smoking status at 3 months (end of treatment), and at 6- and 12-month follow-up. Both continuous and point-prevalent abstinence rates were determined. Saliva cotinine levels were measured in all participants reporting abstinence at each assessment. This study had 80% power to detect a 10% absolute difference in smoking cessation rates between the two treatment conditions (i.e., a 28% quit rate in Study Arm 1 versus a 18% quit rate in Study Arm 2) with alpha set at 0.05. These estimates included an anticipated 15% loss to follow-up over the 12-month study period.

Detailed description: Contingency management as a treatment for substance use disorders involves the use of tangible rewards for confirmed abstinence. There is preliminary evidence that contingency management shows promise as a smoking cessation intervention. An innovative low-cost form of contingency management has been developed in which participants receive the chance to draw vouchers from a fish bowl depending on whether or not their abstinence from tobacco is confirmed by expired-air carbon monoxide. The vouchers can be redeemed for prizes of varying value. This form of contingency management has been shown to be effective in the treatment of a variety of substance use disorders, but has not been investigated in a clinical trial focusing on smoking cessation. Thus, the primary purpose of the proposed study was to investigate the effects of a low-cost prize-based form of contingency management in the treatment of nicotine dependence. To accomplish this objective, we enrolled 103 current smokers into the study. The participants in Study Arm 1 received the contingency management intervention for 8 weeks, and the participants in Study Arm 2 had their smoking status assessed but did not receive the contingency management intervention. Both interventions received brief counseling and nicotine replacement therapy. The counseling was conducted in two 60-minute individual sessions scheduled one week apart with two follow-up phone calls at weeks 3, 4, and 6.

The primary outcome for this study was biochemically-validated smoking status at 3 months (end of treatment), and at 6- and 12-month follow-up. Both continuous and point-prevalent abstinence rates were determined. Saliva cotinine levels were measured in all participants reporting abstinence at each assessment. This study had 80% power to detect a 10% absolute difference in smoking cessation rates between the two treatment conditions (i.e., a 28% quit rate in Study Arm 1 versus a 18% quit rate in Study Arm 2) with alpha set at 0.05. These estimates included an anticipated 15% loss to follow-up over the 12-month study period.

Eligibility criteria: Inclusion Criteria:

* Smoke at least 5 cigarettes per day
* Interested in quitting

Exclusion Criteria:

* Cognitive impairment or unstable psychotic disorder that would significantly interfere with the individual's ability to participate in the study.
* Self-reported problem with alcohol or other drugs during the past three months
* Current use of any smoking cessation medication
* Presence of any contraindications for nicotine patches, lozenges, or gum
* Pregnancy

Primary outcomes:
measure: Abstinence Rate
timeFrame: 52 weeks
Secondary outcomes:
Other outcomes:
Locations:
city: San Francisco
country: United States
facility: VA Medical Center
state: California
Study officials:
affiliation: University of California, San Francisco
name: Timothy P Carmody, Ph.D.
role: PRINCIPAL_INVESTIGATOR
References: