A Needs Survey of Urban Day Shelter Users and Preliminary Evaluation of Alternative Approaches to Combustible Cigarette Cessation: The Exchange Project
Phase: NA
Conditions: Cigarette Smoking
Sponsor: University of Oklahoma

Study Title: A Needs Survey of Urban Day Shelter Users and Preliminary Evaluation of a 
Tobacco Harm Reduction Intervention: The Exchange Project 
 
 
Clinical Trial Registry Number: NCT03743532 
Protocol Date: November 11, 2022 
 
 
 
 

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RESEARCH PROTOCOL OUTLINE
Title of Project:
A Needs Survey of Urban Day Shelter Users and 
Preliminary Evaluation of a Tobacco Harm 
Reduction Intervention: The Exchange Project
Principal Investigator:
Darla E. Kendzor, Ph.D., Department of Family and 
Preventive Medicine, OUHSC 
Co-Investigators:
Michael S. Businelle, Ph.D., Department of Family 
and Preventive Medicine, OUHSC
Adam C. Alexander, Ph.D., Stephenson Cancer 
Center, OUHSC
Summer G. Frank-Pearce, Ph.D., Department of 
Biostatistics and Epidemiology
Jasjit Ahluwalia, MD, School of Public Health, 
Behavioral and Social Science, Brown University
Abstract
Switching from combustible cigarettes to e-cigarette use may be a practical harm 
reduction strategy for vulnerable groups with a high smoking prevalence and a 
low likelihood of cessation. There is substantial evidence that offering financial 
incentives for smoking abstinence is an effective approach for promoting 
smoking cessation in a variety of challenging populations, nevertheless the 
majority are still not able to quit. The combination of offering financial incentives 
to incentivize combustible cigarette abstinence, while offering e-cigarettes as an 
alternative is a novel and potentially powerful harm reduction approach that may 
lead to reduced cigarette consumption in a population that is unlikely to quit 
smoking. The proposed study will provide initial information about the feasibility 
of using this harm reduction strategy to reduce cigarette consumption among 
homeless adults. The aims of the proposed study are to: 1) assess the 
characteristics and needs of Homeless Alliance Day Shelter users (up to 1000 
adults), 2) characterize tobacco and e-cigarette use patterns, tobacco history, 
and past cessation attempts among individuals accessing services at the 
Homeless Alliance Day Shelter, and 3) assess interest in tobacco cessation and 
tobacco harm reduction intervention approaches. A sub-study (N = 60) will 4) 
characterize reductions in cigarette smoking, complete cigarette abstinence, e-
cigarette use, and dual use of combustible cigarettes and e-cigarettes among 
Homeless Alliance Day Shelter guests following the provision of: an e-cigarette 
device and supplies (pods, device charger) or e-cigarette device + financial 
incentives for combustible cigarette abstinence.
 
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A. Specific Aims 
The aims of the proposed study are to: 1) assess characteristics and needs of up 
to 1000 adult males and females who receive services at the Oklahoma City 
Homeless Alliance Day Shelter, 2) characterize tobacco and e-cigarette use 
patterns, tobacco history, and past cessation attempts among individuals using 
services at the Homeless Alliance Day Shelter, and 3) assess interest in tobacco 
cessation and tobacco harm reduction intervention approaches. A sub-study 
(randomized controlled trial; N = 60) will: 4) complete cigarette abstinence, e-
cigarette use, and dual use of combustible cigarettes and e-cigarettes among 
Homeless Alliance Day Shelter guests following the provision of an e-cigarette 
device  with nicotine pods and the ability to earn financial incentives for 
abstaining from combustible cigarettes. Sub-study participants will be randomly 
assigned to: 1) the provision of an e-cigarette device  and supplies/pods through 
4 weeks post-switch along with directions to switch over from combustible 
cigarettes to e-cigarettes exclusively, or 2) the combination of an e-cigarette 
device  and supplies through 4 weeks post-switch and financial rewards to 
incentivize combustible cigarette abstinence, which is based on a previously 
developed incentive schedule for socioeconomically disadvantaged and 
homeless adults.1-3 In both groups, cigarette smoking will be monitored over an 
8-week period to characterize reductions in cigarette smoking, cigarette 
abstinence, dual use (combustible cigarettes and e-cigarettes) and rates of 
exclusive e-cigarette use (i.e., switching). It is anticipated that individuals who are 
provided with an e-cigarette device and supplies and are also incentivized for 
combustible cigarette abstinence will show greater reductions in cigarette 
smoking and be more likely to quit combustible cigarettes and switch to exclusive 
e-cigarette use. The long-term objectives of the survey are to inform 
improvements to the services available to Day Shelter users and to identify 
strategies to help homeless adults quit smoking or reduce harm associated with 
smoking.
B.  Background and Significance 
Poor health is commonplace among homeless adults, who suffer mortality rates 
at least 3 times greater than adults in the general population.4-7 Although 
smoking rates have declined to 13.9% among adults living at or above the 
poverty threshold in the U.S., the prevalence of smoking is 26.1% among those 
living in poverty,8 and at least 70% among homeless adults.9,10 Numerous 
studies have shown that lower socioeconomic status (SES) is associated with a 
reduced likelihood of smoking cessation,11-17 despite a similar number of 
cessation attempts between individuals of lower and higher SES.15 Not 
surprisingly, socioeconomic disadvantage is linked with greater tobacco-related 
cancer incidence and mortality risk.18 Although standard cessation approaches 
are helpful for many,19 alternative strategies may benefit those who are unable to 
quit following traditional evidence-based treatment recommendations. Switching 
from combustible cigarette smoking to e-cigarettes exclusively may be a practical 
harm reduction strategy for some,20 especially vulnerable groups with a high 
smoking prevalence and a reduced likelihood of cessation. The possibility of 
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utilizing e-cigarettes as a harm reduction tool has become more feasible based 
on research demonstrating that e-cigarettes are associated with far fewer harmful 
exposures than cigarette smoking.21-23 Nevertheless, serious concern developed 
over the summer/fall of 2019 about the sudden and rising number of e-cigarette 
and vaping-related lung injury (EVALI) cases. Recent information indicates that 
EVALI was primarily associated with THC-containing vaping products acquired 
from informal sources,24 which contained the product additive - vitamin E 
acetate.25-27 Since September 2019, EVALI hospital admissions have sharply 
declined28 possibly due to increased public awareness of the risks associated 
with THC-containing e-cigarette use, removal of vitamin E acetate from vaping 
products, and law enforcement actions taken to reduce the availability of illicit 
products.29,30 In February 2020, the Centers for Disease Control and Prevention 
(CDC) stopped collecting data on EVALI following the identification of the cause 
of EVALI and the decline in cases.29 
There is substantial evidence that offering financial incentives for cigarette 
abstinence is an effective approach for promoting smoking cessation in a variety 
of challenging populations.31 Dr. Kendzor’s published work1,2,32 as well as 
findings from her ongoing NIH-funded trial (IRB protocol #6260),33,34 indicate that 
offering small escalating financial incentives for smoking abstinence dramatically 
increases cessation rates among socioeconomically disadvantaged smokers 
when incentives are included as an adjunct to standard treatment. The 
combination of offering both financial incentives for smoking abstinence and e-
cigarettes as an alternative to smoking is a novel and potentially powerful harm 
reduction approach for those who are less likely to quit smoking. The proposed 
study will provide information about the feasibility of using alternative intervention 
strategies for socioeconomically disadvantaged and homeless adults who 
continue to smoke. E-cigarettes, alone or in combination with smoking financial 
incentives for cigarette abstinence, may be incorporated into existing tobacco 
cessation programs to decrease the use of combustible cigarettes among 
socioeconomically disadvantaged smokers. New and innovative approaches are 
needed to address worsening tobacco-related health disparities.
C.  Preliminary Studies/Progress Report 
Darla Kendzor earned her Ph.D. in Clinical Psychology from Louisiana State 
University in 2007. She is currently an Associate Professor in the Department of 
Family and Preventive Medicine, and a member of the Cancer Prevention and 
Control Program of the Stephenson Cancer Center Cancer. Dr. Kendzor leads 
the Tobacco Treatment Research Program (TTRP),35,36 which offers free 
counseling and pharmacotherapy to adults from campus and the community 
while collecting data relevant to the process of smoking cessation and facilitating 
recruitment into research studies (IRB protocol #6951). She has published 
extensively in the areas of tobacco cessation interventions, behavioral medicine, 
cancer prevention, and health disparities, and she has a history of external 
funding from the American Cancer Society (ACS) and the National Cancer 
Institute (NCI). Notably, Dr. Kendzor previously completed a randomized 
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controlled trial (RCT) to evaluate the feasibility and short-term effectiveness of 
offering small financial incentives (gift cards) for biochemically verified abstinence 
as an adjunct to the tobacco cessation program offered at the Dallas County 
safety net hospital.1 Dr. Kendzor also completed an NCI-funded follow-up RCT to 
evaluate the longer-term impact of an adjunctive, low-cost intervention offering 
small financial incentives (relative to standard care) on smoking abstinence rates 
among socioeconomically disadvantaged individuals participating in a clinic-
based tobacco cessation program.33 She is currently conducting an NCI-funded 
trial of an automated, mobile incentives-based smoking cessation intervention for 
low-income adults.37 Notably, Dr. Kendzor has a history of published research 
directly relevant to tobacco cessation interventions, and especially within 
socioeconomically disadvantaged populations.2,12,14,38-46 She has also conducted 
tobacco and health-related research within homeless populations specifically.47-52 
Dr. Ahluwalia provides expertise related to e-cigarettes and switching from 
combustible cigarettes to e-cigarettes.21,53-61 Dr. Businelle is a long-time 
collaborator of Dr. Kendzor, and provides additional expertise related to tobacco 
cessation intervention in socioeconomically disadvantaged14,62 and homeless 
populations.2,63 Dr. Frank-Pearce provides biostatistics expertise, and Dr. 
Alexander is a collaborator and trainee of Dr. Kendzor with expertise in tobacco 
cessation interventions and health disparities. 
D. Research Design and Methods
Overview. The current protocol includes a parent survey study, and an 
intervention sub-study. The parent survey study will assess the characteristics 
and needs of Homeless Alliance Day Shelter users (up to 1000 adults), 2) 
characterize tobacco and e-cigarette use patterns, tobacco history, and past 
cessation attempts among individuals accessing services at the Homeless 
Alliance Day Shelter, and 3) assess interest in tobacco cessation and harm 
reduction intervention approaches. Based on responses to screening items 
assessing eligibility criteria, participants will be identified as eligible for the sub-
study. The sub-study (N = 60) will 4) characterize reductions in cigarette 
smoking, smoking abstinence, e-cigarette dual use, and e-cigarette use/switching 
following randomization to: 1) an e-cigarette device  and supplies (device 
charger, pods) for 4 weeks, or 2) e-cigarette and supplies for 4 weeks + financial 
incentives for combustible cigarette abstinence among Homeless Alliance Day 
Shelter guests. Participants will be followed through 8 weeks post-switch date to 
determine whether they continue to use e-cigarettes when the supplies are no 
longer provided. Both the parent survey study and intervention sub-study will 
provide data related to tobacco use, which will be used to support future grant 
funding applications. Both components of the study will take place at the 
Homeless Alliance Day Shelter. 
Survey Study
The current study is a one-time survey of up to 1000 predominantly homeless 
adults accessing services at the Homeless Alliance Day Shelter (1729 N.W. 3rd 
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Street, Oklahoma City, OK 73106). A convenience sample of unique shelter 
guests will be surveyed on several days each month over a one-year period, to 
understand the needs of users in light of seasonal and financial factors that vary 
over the days of the month (e.g., government paychecks) and months of the year 
(e.g., seasonal variations in temperature/weather). Study staff will be stationed 
near the entrance of the day shelter to provide information about the study and 
answer questions. Day Shelter guests who are present at the time when study 
staff are also present will be approached for participation in the study (or they 
may approach us). Study staff will plan to enroll unique survey participants (i.e., 
participants may not participate in the survey twice). 
(Survey Study; pre-COVID – Before March 2020)
Those enrolled will complete a 30-minute survey on a tablet computer at the day 
shelter. Study staff may read the survey questions to the participant and assist 
them in selecting answers on the tablet computer. Participants may be provided 
with reading glasses as needed. Participants will provide information on many 
factors related to homelessness including sociodemographic information, stress 
and discrimination, substance use, mental health history, social support, and 
criminal justice involvement (see survey questionnaire for a full list of questions 
asked during the survey study). Participants will be provided with a $10 gift card. 
 
Sub-Study. 
Overview. The sub-study will examine the feasibility and preliminary efficacy of 
providing financial incentives for combustible cigarette abstinence in combination 
with switching to e-cigarettes among 60 socioeconomically disadvantaged 
Homeless Alliance day shelter users. A total of 60 adults who access the day 
shelter will be recruited to participate in the sub-study. Participants will be 
randomly assigned to one of two groups and followed weekly from 1 week prior 
to switching through 4 weeks after switching, with a final 8-week post-switch 
follow-up. The intervention groups are 1) switching to e-cigarettes (EC), or 2) 
small financial incentives for cigarette abstinence + switching to e-cigarettes (FI + 
EC). Payments will be made via Greenphire clincard, which is similar to a debit 
card.The primary outcome will be carbon monoxide (CO)-verified combustible 
cigarette abstinence (CO) at 4- and 8-weeks post-switch date. Combustible 
cigarette reduction, EC use/switching, and dual use (cigarettes and ECs) will also 
be examined.   
Intervention Groups. All participants will have the opportunity to earn $20 for 
completing study assessments at visits 2 through 7 and $50 for completing visit 8 
(see Table 1).  
Financial Incentives + E-Cigarettes (FI + EC). At baseline (1-week pre-switch), 
participants assigned to this group will be provided with an e-cigarette64 device 
and they will be offered 7 pods to try. Participants will be encouraged to practice 
using the device over the subsequent week (before they switch to exclusive use). 
Participants will be advised to completely switch from combustible cigarettes to 
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the e-cigarette device one week after the baseline visit. On the switch date, they 
will be supplied with refill cartridges in the flavor(s) of their choice and based on 
their pre-switch smoking level. One  pod ≈ 200 puffs and provides the amount of 
nicotine in ≈ 1 pack of cigarettes. Thus, someone who smokes a pack of 
cigarettes each day may be expected to use about 1  pod per day. 
Participants in this group can also earn financial incentives for combustible 
cigarette abstinence. Financial incentives will be earned based on self-reported 
cigarette abstinence and carbon monoxide readings. Beginning with a $20 
payment for self-reporting exclusive e-cigarette use during the past 24 hours 
along with a CO reading of ≤8 ppm on the specified switch day (i.e., one week 
after the enrollment visit), with this amount increasing by $5 with each successive 
weekly self-report of cigarette abstinence along with a CO reading of ≤6 ppm 
(i.e., up to $40 in Greenphire clincard payments at 4 weeks post-switch; $150 
total; see Table 1). After the switch day, participants with CO readings > 6 ppm 
will not earn the payment for that week, and the payment will reset to the starting 
incentive of $20. 
e-Cigarettes (EC). Participants assigned to EC will receive the e-cigarette device 
and the same instructions described previously. Participants in the EC group will 
not earn incentives for cigarette abstinence, rather they will be yoked to a 
participant assigned to the (FI + EC) group and will receive the payment earned 
by that FI + EC participant (up to $150 total). Yoking will reduce or eliminate 
differential attendance rates between groups because participants can earn the 
same amount of money regardless of group assignment. 
Safety Protocol for COVID-19. Data collection may take place inside the 
Homeless Alliance or outside in the homeless alliance courtyard. Participants 
may be asked to wear a mask while completing the survey and other study 
requirements. If participants do not have a mask then one may be provided to 
them. Hand sanitizer will be available to participants and staff. Depending on 
community transmission rates of COVID-19 and the comfort level of the staff, CO 
breath sample collection may take place outside in the courtyard. In addition, the 
number of participants who can be surveyed at once may be limited and social 
distancing guidelines may be implemented. All equipment will be wiped down 
following each use. Staff may wear masks while interacting with participants and 
handling equipment.  
Sub-Study Visits.
Recruitment/Screening (Visit 1, Screening & Scheduling). Eligible 
participants who complete the screening survey will be given a chance to review 
the consent form. Study staff will provide the participant with ample time to 
review the study information and ask questions related to their participation. 
Participants who enroll will be scheduled to return for a baseline visit (typically 
within the next 7 days). The Homeless Shelter Alliance case workers, who work 
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with the shelter’s guests, may encourage their clients to enroll and retain 
participation in the study. 
Baseline (Visit 2). Enrolled participants will be randomly assigned to the EC or 
FI + EC condition. Enrolled participants will be asked to provide their personal 
information (name and phone numbers). Participants will be instructed to switch 
from combustible cigarettes to e-cigarettes at bedtime or 10:00 pm (whichever 
occurs first), on the evening prior to their next scheduled weekly session. They 
will be provided with a EC device and they will have the opportunity to try it out. 
They will be provided with 7  pods (5% nicotine).. They will keep the  pods in 
order to practice using the e-cigarette device over the week prior to their switch 
date. Participants will be advised about earning financial incentives for switching 
to ECs or yoking) beginning the following week on the quit/switch day. The 
schedule of payments will be discussed with all participants (see Table 1). 
Participants will be instructed not to use THC-containing vaping products and 
“street” vaping products, and not to modify or add chemicals to their vaping 
supplies while they are enrolled in the study. They will be counseled to use only 
the supplies that they are given by study staff, and to avoid dual use of e-
cigarettes and cigarettes or other combustible products, including marijuana. 
Participants will receive a $10 Greenphire clincard paymentfor completing this 
visit and they will be provided with a Tracfone (or similar “burner” phone) along 
with a prepaid phone plan that will cover the study period to facilitate 
communication between the participant and study staff. Participants will be 
encouraged to complete this visit as soon as possible, but it can be completed 
within 21 days of visit 1. Enrollment into the sub-study will cease once 60 
participants are enrolled.
Switch Day (Visit 3; 1 week after baseline). Participants will complete self-
report questionnaires on a laptop computer; and expired CO and weight will be 
measured in a private area of the shelter to ensure confidentiality. Participants 
assigned to the FI + EC treatment will receive an additional $20 paymentif their 
expired CO level is < 8 ppm (please note that the less stringent cut-off of 8 ppm 
will be used to verify abstinence on the first post-switch day only, because of the 
recency of switching). EC participants will receive the same payment as their 
yoked FI + EC counterpart. Attempts will be made to contact participants who do 
not attend study visits, in order to obtain self-reported smoking status. 
Participants will be supplied with pods in the flavor(s) of their choice, based off of 
what research staff has available, and based on their pre-switch smoking level. 
1-4 Weeks Post-Switch (Visits 4-7). Participants will complete self-report 
questionnaires on a laptop computer; and expired CO and weight will be 
measured in a private room to ensure confidentiality. Participants randomized to 
the + EC group will receive an additional $20-$40 credit for self-reported 
abstinence and CO readings < 6 ppm. EC participants will receive the same 
payment as their yoked FI + EC counterpart. Additional pods will be provided at 
each weekly visit based on pre-switch smoking levels. Participants will be 
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provided with 1 additional e-cigarette device only if they lose or damage the first 
device. Participants will not be provided with any e-cigarette supplies after visit 7, 
to determine whether they continue to use the e-cigarette on their own. 
8 Weeks Post-Switch (Visit 8). Participants will complete self-report 
questionnaires on a laptop computer; and expired CO and weight will be 
measured in a private area to ensure confidentiality. Participants will receive a 
$50  for completing this final follow-up visit, and participants may keep their study 
phones. Participants will be advised that they can receive free smoking cessation 
treatment through the Tobacco Treatment Research Program36 or the Oklahoma 
Tobacco Helpline65 and provided with contact information.
E.  Statistical Methods  
Survey Study. Day shelter guests (up to 1000) using shelter services will have 
the opportunity to participate in the survey study. Study staff will enroll unique 
participants each month (i.e., participants may participate only once). Descriptive 
statistics will be generated (e.g., frequencies, means) to describe the 
characteristics, needs, tobacco use history, and tobacco treatment preferences 
of study participants, along with correlation and regression analyses to identify 
cross-sectional relationships among variables. For example, we will examine the 
percent of individuals who have used e-cigarettes as a means of quitting smoking 
as well as the percent who are interested in switching to e-cigarettes in the 
future. Tobacco use history and preferences for tobacco cessation treatment will 
be described (e.g., means, frequencies). The relations between tobacco use and 
health, other health behaviors, sociodemographic (e.g., education, race/ethnicity, 
gender), and personal characteristics (e.g., stress and mental health) will be 
examined via correlation and regression analyses. The rate of missing data and 
missing data patterns will be examined before analysis. If the combined missing 
rate is very small, say less than 5%, then we may safely perform the data 
analysis on the available data. If the missing rate is high, then we will explore 
sequential multiple imputation (SMI) as described by Raghunathan et al.66 The 
analysis results from SMI data will be compared with those from the available 
data.
Table 1. Sub-study compensation schedule.
Assessments
Incentive/
Yoking
Total Possible 
Earnings
Visit 1 (Brief Screening) 
$0
$0
$0
Visit 2 (baseline/enrollment; 1 week pre-
switch)
$20
$0
$20
Visit 3 (switch Day)
$20
$20
$40
Visit 4 (1-week post-switch)
$20
up to $25
$45
Visit 5 (2 weeks post-switch)
$20
up to $30
$50
Visit 6 (3 weeks post-switch)
$20
up to $35
$55
Visit 7 (4 weeks post-switch)
$20
up to $40
$60
Visit 8 (8 weeks post-switch)
$50
$0
$50
Total Possible Earnings
$170
$150
$320
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Sub-Study. A sub-sample of survey participants (N = 60) who are currently 
smoking cigarettes will be randomized to one of two intervention groups and 
followed for ten weeks (2-weeks pre-switch through 8-weeks post-switch). This 
pilot study will provide feasibility data and intervention effect sizes for the power 
analysis for a future fully-powered randomized controlled trial. Descriptive 
statistics will be employed (e.g., frequencies, means) to characterize combustible 
cigarette cessation, cigarette reduction, daily EC use, and dual EC and 
combustible cigarette use. The intervention groups will be compared on CO-
verified cigarette abstinence at 4 and 8 weeks after a scheduled switch attempt 
using logistic regression analysis. Secondary analyses will focus on reductions in 
cigarette smoking, EC use/switching, and dual use of ECs and combustible 
cigarettes. 
F.  Gender/Minority/Pediatric Inclusion for Research
The study has no inclusion/exclusion criteria based on gender or race/ethnicity. 
Children < 18 years of age will be excluded from participation in the survey study. 
Children and young adults <21 years of age will be excluded from the sub-study 
because tobacco products are only legally available to adults 21 years and older.
G.  Human Participants
1. Participant Population. The overall survey study will include up to 1000 
individuals recruited from the Homeless Alliance day shelter. Interested 
individuals may be included in the study if they: 1) are able to speak and 
understand English 2) are ≥ 18 years of age. The Day Shelter primarily offers 
services to adults, and rarely children. Children and families are referred to 
other locations that are safer for children (e.g., where individuals are 
screened for felonies and sex offenses). The sub-study will include 60 
individuals who meet the sub-study inclusion criteria: 1) ≥ 21 years of age 
(verified by state driver’s license or ID card), 2) have an expired CO level ≥ 8 
ppm suggestive of current smoking, 3) report currently smoking ≥ 5 cigarettes 
per day, 4) willing and able to attend 8 study visits over an 10 week period (2 
weeks pre-switch through 8 weeks post-switch), 5) interested in switching 
from smoking cigarettes to e-cigarettes, 6) willing to abstain from smoking 
marijuana/cannabis and other combustible tobacco products for the duration 
of the study, 7) able to speak and understand English, 8) demonstrates > 6th 
grade English literacy by earning a score ≥ 4 on the Rapid Estimate of Adult 
Literacy in Medicine-Short Form (REALM-SF; i.e., required to complete 
tablet/laptop questionnaire items), 9) is able to read a 3-sentence selection 
from the consent form, and 10) is not pregnant or breast feeding or planning 
to become pregnant. Individuals may be excluded from participation based on 
professional judgement in situations that would interfere with study 
participation such as apparent alcohol or other substance intoxication, 
uncontrolled psychosis, cognitive impairment, verbal or physical aggression 
directed towards study staff or other guests, or other extreme situations. New 
participants who approach the study team and participants who completed 
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the primary survey in the past (pre-COVID – Before March 2020; before the 
start of the sub-study) may participate in the sub-study if they currently meet 
eligibility criteria. Going forward, potential participants will only be screened 
once for the sub-study and the CitiCare ID Number will be referenced to verify 
that the participant has not been screened more than once. Due to the 
targeted population, bus passes may be provided at visits to assist 
participants in coming back to their next appointment. 
2. Sources of Research Material. Demographic, psychosocial, environmental 
and behavioral data will be collected via traditional self-report questionnaires 
completed in-person on password protected and encrypted OUHSC laptop or 
tablet computers. Expired CO will be collected to confirm self-reported 
smoking status. Height and weight will be collected. Attendance will be noted 
by the research staff each week for sub-study participants. Sub-study 
participants may be contacted by phone to assess tobacco use status if they 
do not attend in-person follow-up sessions.
3. Recruitment and Informed Consent. Participants will be recruited by study 
staff when they access services as the Homeless Alliance Day Shelter. The 
Homeless Shelter Alliance case workers, who work with the shelter’s guests, 
may encourage their clients to enroll and retain participation in the study. 
Individuals will be provided with detailed information about the study, allowed 
as much time as needed to review the consent form, and given the 
opportunity to have their questions answered by knowledgeable research 
staff. Individuals may participate at a later date if they would like to give their 
participation further consideration. Written informed consent will be obtained 
from those who are interested in participating in the sub-study. The parent 
survey study requires a waiver of informed consent because the parent 
survey is anonymous. Instead, participants will review a cover letter that 
briefly describes the survey study and invites them to participate. 
4. Risks. Participation in this study poses minimal risk to participants. However, 
one potential, although unlikely, risk to participants is loss of confidentiality. 
The severity of harm in the case of loss of confidentially may range from mild 
to severe depending upon the individual and the specific circumstances. 
However, the risks of participation in the study are comparable to participation 
in standard tobacco cessation treatment, as loss of confidentially may be 
experienced in either case. 
Risks of e-cigarettes and dual use of cigarettes and e-cigarettes (Sub-
Study only). 
Possible risks of using e-cigarettes. The risk of side effects and adverse 
events are very low. These products are sold online, and at e-cigarette 
specialty stores and convenience stores nationwide, without a prescription. 
Nevertheless, all participants will be screened for pregnancy, and monitored 
for adverse events during the study period. Study personnel will assess for 
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adverse events via self-report at all follow-up visits. Smokers will also be 
provided with a study phone number to report adverse events between follow-
up visits. Serious adverse events will be reported to the Principal Investigator 
(Kendzor) and then to the OUHSC IRB. Participants who have a serious 
adverse event, become pregnant, or begin to breastfeed may be withdrawn 
from the study. The most likely adverse event, nicotine overdose, is 
anticipated to be rare. Mild symptoms (e.g., nausea, headache, disrupted 
sleep) will be handled quickly (e.g., advice to reduce or stop EC use). Lab 
studies of toxin exposure suggest that ECs incur no greater risk to health than 
do conventional cigarettes. ECs generally show lower levels of harmful and 
potentially harmful constituents. EC studies have reported mild and tolerable 
side effects that generally resolved completely over time with continued use 
(90% of cases); the most predominant of which were mouth/throat irritation, 
cough, and headache. In randomized clinical trials, no serious adverse events 
were reported and the e-cigarette group and the nicotine patch groups had 
comparable numbers of adverse events. 
E-Cigarette and Vaping-Related Lung Injury (EVALI). Recent information 
indicates that EVALI is primarily (though not solely) associated with THC-
containing vaping products acquired from informal sources,24 which contained 
the product additive - vitamin E acetate.25-27 A total of 2,711 hospitalized 
EVALI cases (including deaths) have been reported to the Centers for 
Disease Control and Prevention, with 60 confirmed deaths. However, since 
September 2019, EVALI hospital admissions have sharply declined to only a 
few cases in January 2020,28 possibly due to increased public awareness of 
of the risks associated with THC-containing e-cigarette use, removal of 
vitamin E acetate from vaping products, and law enforcement actions taken to 
reduce the availability of illicit products.30 Symptoms of EVALI include: 
coughing, shortness of breath, chest pain, nausea, vomiting, stomach pain, 
diarrhea, fever, chills, and weight loss.67 Due to the determination of the 
causes of EVALI and the sharp decline in cases, the CDC is no longer 
tracking EVALI.
Risk of dual use of cigarettes and e-cigarettes: The concern about smokers 
engaging in dual use is that they will substantially increase their uptake of 
nicotine, leading to nicotine overdose. The symptoms of nicotine overdose 
include nausea, vomiting, dizziness, headache, and rapid heart rate. In a 
previous trial with ECs, none of the participants reported any indication of 
nicotine overdose in their dual use of e-cigarettes and conventional 
cigarettes. In fact, most reduced their level of conventional cigarette use in 
proportion with their uptake of e-cigarettes. Preliminary analyses (n=20) from 
another randomized trial that is investigating the use of ECs by caregivers as 
a means of reducing their children’s secondhand smoke exposure (i.e., 
parents asked to use EC anytime they are in the home, car, or around their 
child), indicate that caregivers decreased in their level of salivary cotinine (a 
metabolite of nicotine; Mbaseline=447.9 to M3-mo=314.8). Caregivers’ also 
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reported reduction in number of tobacco cigarettes per day from baseline to 
3- month follow-up (Mbaseline=19.6 to M3-mo=9.5). Consistent with these 
findings, parents reported no adverse events, no serious adverse events and 
specifically no nicotine overdose event.
5. Protections against Risk. Because survey participants can only participate 
once in the parent survey, we will track participant names and shelter ID 
numbers. These identifiers will be kept in password-protected data file that is 
separate from all other questionnaire data. Thus, specific survey participants 
cannot be linked with their questionnaire responses. This tracking file will be 
destroyed after all participants complete the study. In the questionnaire data 
files, each participant will be assigned an identification number that will be 
utilized in place of names. Informed consent documents will be collected 
electronically or stored in locked filing cabinets at the TSET Health Promotion 
Research Center. Electronic data will be maintained on the investigators’ 
computers, and all computers will be encrypted and password protected. All 
project staff will receive training focused on each of the following topics: 1) 
project rationale and objectives, 2) the informed consent process, 3) general 
data collection procedures (e.g., computer data collection, privacy), and 4) 
use of the Vitalograph CO ecolyzer. Participants will be educated about the 
potential health risks of e-cigarette use (i.e., long-term heath impact is 
unknown); and dual use of e-cigarettes and combustible cigarettes (i.e., 
possible adverse health impact). Study staff will monitor sub-study 
participants for nicotine-related side effects/adverse events at each visit and 
participants will be provided with a phone number to call if they have 
concerns between visits. For sub-study participants who miss a study visit, 
staff will attempt to follow-up with them every week via phone to monitor the 
use of nicotine products during the study period.
Potential Benefits. The knowledge gained from this study may be used to 
improve our understanding of the characteristics and needs of homeless 
adults and inform shelter decision-making regarding the availability of 
services. For sub-study participants, it is possible that these interventions will 
reduce harm by reducing combustible cigarette use and increasing the 
likelihood of switching to exclusive e-cigarette use.
6. Risks in relation to Benefits. The current study involves minimal risk. The 
sub-study risks are like that of participation in any intensive smoking 
cessation intervention (e.g., loss of confidentiality, nicotine withdrawal, 
nicotine product side effects). Participants receiving any of the interventions in 
the sub-study may benefit from cigarette reduction/cessation, and participants 
will be compensated for their time and effort. Conversely, continued 
combustible cigarette smoking is known to cause cancer, cardiovascular and 
lung disease. 
H.  Data and Safety Monitoring Plan 
The study poses minimal risk to participants, therefore continuous monitoring and 
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reporting of events will be undertaken by the principal investigator (Dr. Kendzor) 
and other OUHSC faculty co-investigators (Drs. Alexander and Businelle). 
Unanticipated problems/adverse events will be promptly reported to the IRB by 
the research coordinator or study staff. Possible (though unlikely) adverse events 
might include side effects from e-cigarettes as well as compromised data 
security. Sub-study participants will be scheduled for weekly visits and 
medication side effects will be assessed. Procedures to minimize the risk of loss 
of confidentiality are described in section G under the heading Protections 
against Risk.
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