Smoking
Conditions
Brief summary
Incentives can be used to facilitate the acquisition of many healthy behaviors, such as smoking cessation. However, there is much room for improvement in the use of incentives. This study investigates how two aspects of providing incentives influence the effectiveness of using incentives to promote smoking cessation. One aspect is the criterion for providing incentives, e.g., whether to require smoking cessation before providing an incentive or to provide incentives following smoking reductions. The other aspect being investigated is whether it is best to use a fixed incentive amount or an amount that increases with continued cessation success.
Interventions
BEHAVIORALContingency Management
incentives are available for reduced smoking on each study visit which occur each weekday.
Sponsors
National Institute on Drug Abuse (NIDA)
National Institutes of Health (NIH)
The University of Texas Health Science Center at San Antonio
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Daily Smokers smoking a pack or more of cigarettes a day who are able to report to the study site each work day for about 5 minutes for around 3 months. Subjects must also have a breath CO level indicative of smoking at this level, and most report smoking for at least two years. Subjects must intend on quitting smoking. \-
Exclusion criteria
Participation in another study by this group within the past year. Inability to give informed consent. Incapable of attendance each workday during the morning hours. \-
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Breath Carbon Monoxide Levels Indicating Smoking Abstinence During the Study, i.e., the Number of Breath Samples With Carbon Monoxide (CO) Levels Less Than 3 Parts Per Million (Ppm) | daily for breath CO |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Average Number Cigarettes Reported Smoked Each Day in the Past Week Measured at Follow-up Six Months After Entry Into the Study | past week at follow-up six months after study entry | average number cigarettes reported smoked each day in the past week at follow up six months after study entry |
Countries
United States
Participant flow
Recruitment details
Individuals smoking at least 15 cigarettes per day that are at least 18 years old, and deliver a breath CO level greater than or equal to 15 ppm were recruited in a University setting from the general community.
Pre-assignment details
Five weekdaily visits that took about 5 minutes occurred before randomization. 328 individuals consented and of these 239 completed baseline and were randomized. Which set of three study arms individuals were randomly assigned to depended on whether they successfully delivered a C) \< 3 ppm during this baseline for which they earned an incentive.
Participants by arm
| Arm | Count |
|---|---|
| Shaping Intervention for Hard-to-treat Smokers Shaping intervention for hard-to-treat smokers: Smokers who did not deliver a breath CO \< 3 ppm in first five weekday sessions randomly assigned to receive incentives based upon a percentile schedule. | 36 |
| Fixed Criterion Intervention for Hard-to-treat Smokers fixed criterion intervention for hard-to-treat smokers: Smokers who did not deliver a breath CO \< 3 ppm in first five weekday sessions randomly assigned to receive incentives for COs \< 3 ppm. | 38 |
| Non Contingent Incentives Available to Hard to Treat Smokers Non contingent incentives available to hard to treat smokers: Smokers who did not deliver a breath CO \< 3 ppm in first five weekday sessions randomly assigned to receive incentives non-contingently on a random basis. | 18 |
| Ascending Incentives Values Used in Smokers With Early Success Ascending incentives values used in Smokers with Early Success: Smokers who did deliver a breath CO \< 3 ppm in first five weekday sessions randomly assigned to receive incentives that escalate in value with each delivery. | 60 |
| Fixed Value Incentives Are Used in Smokers With Early Success fixed value incentives are used in Smokers with Early Success: Smokers who did deliver a breath CO \< 3 ppm in first five weekday sessions randomly assigned to receive incentives that are fixed in value | 58 |
| Non Contingent Incentives Are Available to Smokers With Early Non contingent incentives are available to Smokers with Early Success: Smokers who did deliver a breath CO \< 3 ppm in first five weekday sessions randomly assigned to receive incentives that are non-contingently delivered on a random basis. | 29 |
| Total | 239 |
Baseline characteristics
| Characteristic | Fixed Criterion Intervention for Hard-to-treat Smokers | Non Contingent Incentives Available to Hard to Treat Smokers | Ascending Incentives Values Used in Smokers With Early Success | Shaping Intervention for Hard-to-treat Smokers | Fixed Value Incentives Are Used in Smokers With Early Success | Non Contingent Incentives Are Available to Smokers With Early | Total |
|---|---|---|---|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 1 Participants | 0 Participants | 1 Participants | 0 Participants | 0 Participants | 0 Participants | 2 Participants |
| Age, Categorical Between 18 and 65 years | 37 Participants | 18 Participants | 59 Participants | 36 Participants | 58 Participants | 29 Participants | 237 Participants |
| Age Continuous | 43.3 years STANDARD_DEVIATION 12.8 | 43.1 years STANDARD_DEVIATION 11.2 | 41.9 years STANDARD_DEVIATION 12.9 | 44.8 years STANDARD_DEVIATION 12.2 | 41.3 years STANDARD_DEVIATION 11.8 | 40.6 years STANDARD_DEVIATION 10 | 42.5 years STANDARD_DEVIATION 12 |
| Region of Enrollment United States | 38 participants | 18 participants | 60 participants | 36 participants | 58 participants | 29 participants | 239 participants |
| Sex: Female, Male Female | 12 Participants | 7 Participants | 25 Participants | 12 Participants | 26 Participants | 16 Participants | 98 Participants |
| Sex: Female, Male Male | 26 Participants | 11 Participants | 35 Participants | 24 Participants | 32 Participants | 13 Participants | 141 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk | EG003 affected / at risk | EG004 affected / at risk | EG005 affected / at risk |
|---|---|---|---|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — | — / — | — / — | — / — | — / — |
| other Total, other adverse events | 0 / 36 | 0 / 38 | 0 / 18 | 0 / 60 | 0 / 58 | 0 / 29 |
| serious Total, serious adverse events | 0 / 36 | 0 / 38 | 0 / 18 | 0 / 60 | 0 / 58 | 0 / 29 |
Outcome results
Primary
Breath Carbon Monoxide Levels Indicating Smoking Abstinence During the Study, i.e., the Number of Breath Samples With Carbon Monoxide (CO) Levels Less Than 3 Parts Per Million (Ppm)
Time frame: daily for breath CO
Population: all subjects randomized to condition
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Shaping Intervention for Hard-to-Treat Smokers | Breath Carbon Monoxide Levels Indicating Smoking Abstinence During the Study, i.e., the Number of Breath Samples With Carbon Monoxide (CO) Levels Less Than 3 Parts Per Million (Ppm) | 2 number breath samples < 3 ppm CO |
| Fixed Criterion Intervention for Hard-to-Treat Smokers | Breath Carbon Monoxide Levels Indicating Smoking Abstinence During the Study, i.e., the Number of Breath Samples With Carbon Monoxide (CO) Levels Less Than 3 Parts Per Million (Ppm) | 3.5 number breath samples < 3 ppm CO |
| Non Contingent Incentives Available to Hard-to-Treat Smokers | Breath Carbon Monoxide Levels Indicating Smoking Abstinence During the Study, i.e., the Number of Breath Samples With Carbon Monoxide (CO) Levels Less Than 3 Parts Per Million (Ppm) | 0 number breath samples < 3 ppm CO |
| Ascending Incentive Values Used in Smokers With Early Success | Breath Carbon Monoxide Levels Indicating Smoking Abstinence During the Study, i.e., the Number of Breath Samples With Carbon Monoxide (CO) Levels Less Than 3 Parts Per Million (Ppm) | 58.5 number breath samples < 3 ppm CO |
| Fixed Value Incentives Are Used in Smokers With Early Success | Breath Carbon Monoxide Levels Indicating Smoking Abstinence During the Study, i.e., the Number of Breath Samples With Carbon Monoxide (CO) Levels Less Than 3 Parts Per Million (Ppm) | 49.5 number breath samples < 3 ppm CO |
| Non Contingent Incentives Are Available to Smokers With Early | Breath Carbon Monoxide Levels Indicating Smoking Abstinence During the Study, i.e., the Number of Breath Samples With Carbon Monoxide (CO) Levels Less Than 3 Parts Per Million (Ppm) | 28 number breath samples < 3 ppm CO |
Secondary
Average Number Cigarettes Reported Smoked Each Day in the Past Week Measured at Follow-up Six Months After Entry Into the Study
average number cigarettes reported smoked each day in the past week at follow up six months after study entry
Time frame: past week at follow-up six months after study entry
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Shaping Intervention for Hard-to-Treat Smokers | Average Number Cigarettes Reported Smoked Each Day in the Past Week Measured at Follow-up Six Months After Entry Into the Study | 12.8 cigarettes per day | Standard Deviation 12 |
| Fixed Criterion Intervention for Hard-to-Treat Smokers | Average Number Cigarettes Reported Smoked Each Day in the Past Week Measured at Follow-up Six Months After Entry Into the Study | 12.6 cigarettes per day | Standard Deviation 7.7 |
| Non Contingent Incentives Available to Hard-to-Treat Smokers | Average Number Cigarettes Reported Smoked Each Day in the Past Week Measured at Follow-up Six Months After Entry Into the Study | 15.1 cigarettes per day | Standard Deviation 8.2 |
| Ascending Incentive Values Used in Smokers With Early Success | Average Number Cigarettes Reported Smoked Each Day in the Past Week Measured at Follow-up Six Months After Entry Into the Study | 11.5 cigarettes per day | Standard Deviation 9.9 |
| Fixed Value Incentives Are Used in Smokers With Early Success | Average Number Cigarettes Reported Smoked Each Day in the Past Week Measured at Follow-up Six Months After Entry Into the Study | 11.1 cigarettes per day | Standard Deviation 8.2 |
| Non Contingent Incentives Are Available to Smokers With Early | Average Number Cigarettes Reported Smoked Each Day in the Past Week Measured at Follow-up Six Months After Entry Into the Study | 8.2 cigarettes per day | Standard Deviation 7.2 |