Trial Outcomes & Findings for Increasing Contingency Management Success in Smoking Cessation (NCT NCT00273793)

Results Overview

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

328 participants

Primary outcome timeframe

daily for breath CO

Results posted on

2012-06-21

Participant Flow

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.

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.

Participant milestones

Participant milestones
Measure	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.	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.	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.	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.	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	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.
Overall Study STARTED	36	38	18	60	58	29
Overall Study COMPLETED	36	38	18	60	58	29
Overall Study NOT COMPLETED	0	0	0	0	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Increasing Contingency Management Success in Smoking Cessation

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Shaping Intervention for Hard-to-treat Smokers n=36 Participants 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.	Fixed Criterion Intervention for Hard-to-treat Smokers n=38 Participants 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.	Non Contingent Incentives Available to Hard to Treat Smokers n=18 Participants 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.	Ascending Incentives Values Used in Smokers With Early Success n=60 Participants 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.	Fixed Value Incentives Are Used in Smokers With Early Success n=58 Participants 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	Non Contingent Incentives Are Available to Smokers With Early n=29 Participants 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.	Total n=239 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants
Age, Categorical Between 18 and 65 years	36 Participants n=5 Participants	37 Participants n=7 Participants	18 Participants n=5 Participants	59 Participants n=4 Participants	58 Participants n=21 Participants	29 Participants n=8 Participants	237 Participants n=8 Participants
Age, Categorical >=65 years	0 Participants n=5 Participants	1 Participants n=7 Participants	0 Participants n=5 Participants	1 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	2 Participants n=8 Participants
Age Continuous	44.8 years STANDARD_DEVIATION 12.2 • n=5 Participants	43.3 years STANDARD_DEVIATION 12.8 • n=7 Participants	43.1 years STANDARD_DEVIATION 11.2 • n=5 Participants	41.9 years STANDARD_DEVIATION 12.9 • n=4 Participants	41.3 years STANDARD_DEVIATION 11.8 • n=21 Participants	40.6 years STANDARD_DEVIATION 10.0 • n=8 Participants	42.5 years STANDARD_DEVIATION 12.0 • n=8 Participants
Sex: Female, Male Female	12 Participants n=5 Participants	12 Participants n=7 Participants	7 Participants n=5 Participants	25 Participants n=4 Participants	26 Participants n=21 Participants	16 Participants n=8 Participants	98 Participants n=8 Participants
Sex: Female, Male Male	24 Participants n=5 Participants	26 Participants n=7 Participants	11 Participants n=5 Participants	35 Participants n=4 Participants	32 Participants n=21 Participants	13 Participants n=8 Participants	141 Participants n=8 Participants
Region of Enrollment United States	36 participants n=5 Participants	38 participants n=7 Participants	18 participants n=5 Participants	60 participants n=4 Participants	58 participants n=21 Participants	29 participants n=8 Participants	239 participants n=8 Participants

PRIMARY outcome

Timeframe: daily for breath CO

Population: all subjects randomized to condition

Outcome measures

Outcome measures
Measure	Shaping Intervention for Hard-to-Treat Smokers n=36 Participants	Fixed Criterion Intervention for Hard-to-Treat Smokers n=38 Participants	Non Contingent Incentives Available to Hard-to-Treat Smokers n=18 Participants	Ascending Incentive Values Used in Smokers With Early Success n=60 Participants	Fixed Value Incentives Are Used in Smokers With Early Success n=58 Participants	Non Contingent Incentives Are Available to Smokers With Early n=29 Participants
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 Interval 0.0 to 12.5	3.5 number breath samples < 3 ppm CO Interval 0.0 to 39.0	0 number breath samples < 3 ppm CO Interval 0.0 to 12.0	58.5 number breath samples < 3 ppm CO Interval 15.0 to 64.0	49.5 number breath samples < 3 ppm CO Interval 25.0 to 61.0	28 number breath samples < 3 ppm CO Interval 6.0 to 59.0

SECONDARY outcome

Timeframe: 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