Trial Outcomes & Findings for E-Cigarettes and Financial Incentives to Promote Tobacco Harm Reduction Among Adults Accessing Shelter Services (NCT NCT03743532)

NCT ID: NCT03743532

Last Updated: 2025-02-21

Results Overview

Self-reported and Carbon monoxide-verified (\<=6 ppm) combustible cigarette smoking abstinence during the previous 7 days (missing = smoking)

• Recruitment status: COMPLETED
• Study phase: NA
• Target enrollment: 60 participants
• Primary outcome timeframe: 4 weeks post-switch date
• Results posted on: 2025-02-21

Participant Flow

Participant milestones

Measure	E-Cigarette Switching (EC) Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	Financial Incentives + E-cigarette Switching Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.
Overall Study STARTED	30	30
Overall Study COMPLETED	14	13
Overall Study NOT COMPLETED	16	17

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

1 participant excluded from analyses because of out of range value (i.e., 2400 cigarettes per day).

Baseline characteristics by cohort

Measure	E-Cigarette Switching (EC) n=30 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	E-cigarette Switching + Financial Incentives (EC+FI) n=30 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.	Total n=60 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=30 Participants	0 Participants n=30 Participants	0 Participants n=60 Participants
Age, Categorical Between 18 and 65 years	29 Participants n=30 Participants	28 Participants n=30 Participants	57 Participants n=60 Participants
Age, Categorical >=65 years	1 Participants n=30 Participants	2 Participants n=30 Participants	3 Participants n=60 Participants
Age, Continuous	50.30 Years STANDARD_DEVIATION 10.98 • n=30 Participants	47.23 Years STANDARD_DEVIATION 10.94 • n=30 Participants	48.77 Years STANDARD_DEVIATION 10.98 • n=60 Participants
Sex: Female, Male Female	7 Participants n=30 Participants	8 Participants n=30 Participants	15 Participants n=60 Participants
Sex: Female, Male Male	23 Participants n=30 Participants	22 Participants n=30 Participants	45 Participants n=60 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants n=30 Participants	4 Participants n=30 Participants	4 Participants n=60 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	30 Participants n=30 Participants	26 Participants n=30 Participants	56 Participants n=60 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=30 Participants	0 Participants n=30 Participants	0 Participants n=60 Participants
Race (NIH/OMB) American Indian or Alaska Native	1 Participants n=30 Participants	2 Participants n=30 Participants	3 Participants n=60 Participants
Race (NIH/OMB) Asian	0 Participants n=30 Participants	0 Participants n=30 Participants	0 Participants n=60 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=30 Participants	0 Participants n=30 Participants	0 Participants n=60 Participants
Race (NIH/OMB) Black or African American	7 Participants n=30 Participants	13 Participants n=30 Participants	20 Participants n=60 Participants
Race (NIH/OMB) White	19 Participants n=30 Participants	13 Participants n=30 Participants	32 Participants n=60 Participants
Race (NIH/OMB) More than one race	3 Participants n=30 Participants	2 Participants n=30 Participants	5 Participants n=60 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=30 Participants	0 Participants n=30 Participants	0 Participants n=60 Participants
Region of Enrollment United States	30 participants n=30 Participants	30 participants n=30 Participants	60 participants n=60 Participants
Currently Experiencing Homelessness	24 Participants n=30 Participants	22 Participants n=30 Participants	46 Participants n=60 Participants
Cigarettes Smoked Per Day	15.73 Number of cigarettes smoked per day STANDARD_DEVIATION 12.13 • n=30 Participants • 1 participant excluded from analyses because of out of range value (i.e., 2400 cigarettes per day).	16.28 Number of cigarettes smoked per day STANDARD_DEVIATION 11.08 • n=29 Participants • 1 participant excluded from analyses because of out of range value (i.e., 2400 cigarettes per day).	16.00 Number of cigarettes smoked per day STANDARD_DEVIATION 11.53 • n=59 Participants • 1 participant excluded from analyses because of out of range value (i.e., 2400 cigarettes per day).

PRIMARY outcome

Timeframe: 4 weeks post-switch date

Population: Participants with missing cigarette smoking status were considered smoking.

Self-reported and Carbon monoxide-verified (<=6 ppm) combustible cigarette smoking abstinence during the previous 7 days (missing = smoking)

Outcome measures

Measure	E-Cigarette Switching (EC) n=30 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	E-cigarette Switching (EC) + Financial Incentives n=30 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.
Combustible Cigarette Cessation	1 Participants	4 Participants

PRIMARY outcome

Timeframe: 8 weeks post-quit/switch date

Population: Participants with missing cigarette smoking status were considered smoking.

Self-reported and Carbon monoxide-verified (<=6 ppm) combustible cigarette smoking abstinence during the previous 7 days (missing = smoking)

Outcome measures

Measure	E-Cigarette Switching (EC) n=30 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	E-cigarette Switching (EC) + Financial Incentives n=30 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.
Combustible Cigarette Cessation	3 Participants	4 Participants

SECONDARY outcome

Timeframe: 4 weeks post-switch

Population: Participants with missing smoking status were excluded from the analyses (i.e., complete case analysis).

Self-reported and Carbon monoxide-verified (<=6 ppm) combustible cigarette smoking abstinence during the previous 7 days (missing excluded)

Outcome measures

Measure	E-Cigarette Switching (EC) n=16 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	E-cigarette Switching (EC) + Financial Incentives n=15 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.
Combustible Cigarette Cessation (Complete Case Analysis)	1 Participants	4 Participants

SECONDARY outcome

Timeframe: 8 weeks post-switch

Population: Participants with missing smoking status data were excluded from the analyses (i.e., complete case analysis).

Self-reported and Carbon monoxide-verified (<=6 ppm) combustible cigarette smoking abstinence during the previous 7 days (missing excluded)

Outcome measures

Measure	E-Cigarette Switching (EC) n=14 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	E-cigarette Switching (EC) + Financial Incentives n=13 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.
Combustible Cigarette Cessation (Complete Case Analysis)	3 Participants	4 Participants

SECONDARY outcome

Timeframe: 4 weeks post-switch

Change in expired CO (ppm) from baseline to 4 weeks post-switch-date.

Outcome measures

Measure	E-Cigarette Switching (EC) n=16 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	E-cigarette Switching (EC) + Financial Incentives n=15 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.
Expired Carbon Monoxide (CO), Parts Per Million (Ppm), Change From Baseline	0.31 ppm Standard Deviation 12.10	-8.73 ppm Standard Deviation 7.77

SECONDARY outcome

Timeframe: 8 week post-switch

Change in expired CO (ppm) from baseline to 8 weeks post-switch-date

Outcome measures

Measure	E-Cigarette Switching (EC) n=14 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	E-cigarette Switching (EC) + Financial Incentives n=13 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.
Expired Carbon Monoxide (CO), Parts Per Million (Ppm), Change From Baseline	-4.57 ppm Standard Deviation 8.91	-7.23 ppm Standard Deviation 9.35

SECONDARY outcome

Timeframe: 4 weeks post-switch

The total number of days of combustible cigarette smoking during the past week

Outcome measures

Measure	E-Cigarette Switching (EC) n=16 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	E-cigarette Switching (EC) + Financial Incentives n=15 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.
Days of Combustible Cigarette Smoking, Past 7 Days	4.25 Days Standard Deviation 2.77	2.20 Days Standard Deviation 2.60

SECONDARY outcome

Timeframe: 8 weeks post-switch

The total number of days of combustible cigarette smoking during the past 7 days

Outcome measures

Measure	E-Cigarette Switching (EC) n=14 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	E-cigarette Switching (EC) + Financial Incentives n=11 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.
Days of Combustible Cigarette Smoking, Past 7 Days	2.79 Days Standard Deviation 2.33	3.73 Days Standard Deviation 3.32

SECONDARY outcome

Timeframe: 4 weeks post-switch

The total number of days where e-cigarettes were used during the past 7 days

Outcome measures

Measure	E-Cigarette Switching (EC) n=14 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	E-cigarette Switching (EC) + Financial Incentives n=14 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.
Days of E-cigarette Use, Past 7 Days	3.64 Days Standard Deviation 2.84	5.07 Days Standard Deviation 2.84

SECONDARY outcome

Timeframe: 8 weeks post-switch

The total number of days on which E-cigarettes were used during the past 7 days

Outcome measures

Measure	E-Cigarette Switching (EC) n=13 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	E-cigarette Switching (EC) + Financial Incentives n=11 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.
Days of E-cigarette Use, Past 7 Days	4.15 Days Standard Deviation 3.11	4.18 Days Standard Deviation 3.25

SECONDARY outcome

Timeframe: 4 weeks post-switch

The number of participants who completed the smoking status follow-up assessment.

Outcome measures

Measure	E-Cigarette Switching (EC) n=30 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	E-cigarette Switching (EC) + Financial Incentives n=30 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.
Follow-Up Completion	16 Participants	15 Participants

SECONDARY outcome

Timeframe: 8 weeks post-switch

The number of participants who completed the smoking status follow-up assessment

Outcome measures

Measure	E-Cigarette Switching (EC) n=30 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes. They will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. E-cigarette: Participants will receive an e-cigarette device and pods. Each participant in this group will be yoked to a participant in the financial incentives group, thus receiving equal payments. Yoking will reduce or eliminate differential attendance rates between groups because participants have the opportunity to earn the same amount of money regardless of group assignment. Participants will be followed for the first 4 weeks following a scheduled quit attempt.	E-cigarette Switching (EC) + Financial Incentives n=30 Participants Participants will be asked to completely switch from cigarettes to e-cigarettes, and they will receive an e-cigarette device and pods during the first 4 weeks following a scheduled switch date. Participants will also receive weekly financial incentives for biochemically-verified cigarette abstinence during the first 4 weeks following the switch date. Financial incentives + E-cigarette: Participants will receive an e-cigarette device and pods and the opportunity to earn financial incentives for biochemically-verified cigarette smoking abstinence, credited to a gift card with biochemical evidence of smoking abstinence during the first 4 weeks following a scheduled quit attempt.
Follow-Up Completion	14 Participants	13 Participants

Adverse Events

E-Cigarette Switching (EC)

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

E-cigarette Switching (EC) + Financial Incentives

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Darla E. Kendzor

The University of Oklahoma Health Sciences

Phone: (405) 271-7848

Email: Darla-Kendzor@ouhsc.edu

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place