Evaluations of Alcohol Warning Labels
Phase: NA
Conditions: Oral Cancer, Esophageal Cancer, Larynx Cancer, Alcohol Drinking
Sponsor: University of Connecticut

Study Protocol 
 
Title of Project: Evaluations of Alcohol Warning Labels 
NCT #: NCT06129487 
Protocol Version: 1/26/2024 
 
 
 
 

1. Study Synopsis 
Title/Acronym: 
Evaluations of Alcohol Warning Labels 
Funding Source(s): 
NIH  
Investigational Intervention(s) and/or Product(s): Different types of alcohol warning labels  
Purpose: To test the effectiveness of alcohol warning labels to communicate the cancer risk 
of alcohol 
Objectives: To examine alcohol consumers’ reactions to alcohol warning labels that feature 
narrative or non-narrative content 
Design/Methodology: Randomized experiment  
Outcome Measures: Affective and cognitive responses toward alcohol warning labels, 
beliefs, attitudes, intentions, and behaviors related to alcohol  
Study Population: U.S. adult (21+) moderate and heavy drinkers  
Study Duration: 1 minute for the screening survey; 15 minutes for the main experiment; 5 
minutes for the follow-up survey.  
Settings/Locations: Surveys will be conducted online  
 
2. Rationale/Significance 
Alcohol use is a major preventable risk factor for cancer in the United States, but few 
Americans are aware of the risk (R. Ma & Ma, 2022). A promising approach to raising 
awareness of risk is to include pictorial warning labels (PWLs) on alcohol-containing products, 
but there is a limited understanding of the design and impact of such warnings (Clarke et al., 
2021; Z. Ma, 2022). The proposed project is relevant to public health because determining 
the effectiveness of pictorial warning labels that feature narrative content to communicate 
cancer risk can raise awareness and potentially reduce harm.   
3. Purpose and Objectives 
3.1. Purpose 
The proposed project aims to evaluate the impact of narrative (vs. non-narrative) 
PWLs on visual attention, message reactance, risk perceptions, and intentions to 
reduce and stop drinking. 
3.2. Objectives 
Specific Aim 1: Determine the effect of narrative PWLs on visual attention and 
message reactance. 

Specific Aim 2: Determine the effect of narrative PWLs on risk perceptions and 
intentions. 
3.3. Hypotheses/Research Questions 
H1: We hypothesize that narrative PWLs will lead to greater visual attention and 
less message reactance than non-narrative PWLs.  
H2: We hypothesize that narrative PWLs will lead to higher risk perceptions and 
higher intentions to reduce and stop drinking than non-narrative PWLs.  
4. Study Design 
To examine the effect of narrative and non-narrative PWLs on visual attention, 
reactance, risk perceptions, and behavioral intentions, we will employ an online 
randomized experiment through the Qualtrics survey platform, which can be configured 
to redirect participants to Sticky by Tobii, a webcam-based eye-tracking platform. We 
plan to recruit adult moderate and heavy alcohol users via Prolific, a research company 
that provides online study panels. Participants will first be invited to participate in an 
online screening survey. Eligible participants will be invited to participate in the main 
experiment. In the main experiment, participants will first answer questions concerning 
baseline alcohol consumption and other background information. Then they will engage 
with a webcam-based eye-tracking task through Sticky by Tobii. Participants will first 
read instructions and tips related to completing the eye-tracking task. They will 
complete a brief calibration procedure and be presented with either three narrative 
PWLs or three non-narrative PWLs. Sticky by Tobii will record participants’ gaze, thereby 
measuring visual attention to each PWL. After viewing each PWL, participants will 
answer a few questions. After viewing all three PWLs, they will answer questions based 
on all images combined. Upon study completion, participants will be compensated. A 
follow-up survey will be sent to participants after two weeks, which includes questions 
about their drinking behaviors and risk perceptions. 
5. Analytical Plan  
We will analyze the data using the statistical software SPSS. First, we will use descriptive 
statistics to provide study sample characteristics. Then, we will conduct independent-
samples t-tests and chi-square tests to check whether there are differences in background 
variables (i.e., demographic characteristics and baseline alcohol consumption) between 
conditions. If there are a significant association between the experimental condition and 
a specific background variable(s), we will control for this variable(s) in all analyses. To test 
the first hypothesis, we will conduct multilevel mixed-effects linear regressions to 
examine the effect of narrative (vs. non-narrative) PWLs time until noticed, time viewed, 
and number of visits, and reactance. We will also control for repeated measures because 
each participant will view three PWLs that vary in cancer type within their assigned 

condition. We will check the assumptions of these analyses. To test the second hypothesis, 
we will conduct independent-samples t-tests to examine the effect of PWLs type 
(narrative vs. non-narrative) on risk perceptions and behavioral intentions when there are 
no differences in the distribution of background variables between conditions. If there 
are differences in the distribution, we will conduct a series of analyses of covariance 
(ANCOVA). Assumptions of these analyses will be checked. 
6. Study Participants 
6.1. Study Population 
Participants will be recruited through the Prolific panel. Participants must meet both criteria 
for eligibility: (1) be at least 21 years old; (2) have consumed more than three alcoholic drinks 
per week over the past year, which is to ensure they are current moderate or heavy drinkers 
defined by the Centers for Disease Control and Prevention (2018); and (3) be willing to 
participate in remote eye tracking tasks and have necessary technical support to complete 
remote eye tracking tasks (i.e., having access to high-speed Internet and a 
computer/tablet/phone equipped with a high-speed camera). We will carry out the initial 
screening over an online survey.  
6.2. Number of Participants 
Number of people expected to be screened: 3,000  
Number of people expected to be enrolled: 800.  
6.2.1. Sample Size  
 No previously published work has examined the effect of narrative (vs. non-narrative) 
PWLs on visual attention and reactance. In our preliminary work, we conducted an 
online experiment testing the effect of PWLs type among adult moderate and heavy 
drinkers. We found that participants who saw non-narrative PWLs reported significantly 
higher reactance to the warnings than those who saw narrative PWLs (r = .19). 
Therefore, in the proposed project, we will use the effect size of r = .19 to estimate the 
sample size. With the alpha level set at .05, we will need 213 participants to achieve a 
statistical power of .80. The final sample size needs to account for possible failure to (1) 
complete the eye-tracking task and (2) generate usable eye-tracking data for those who 
complete the task. Based on a recent remote eye-tracking study (Chen-Sankey et al., 
2023) and information provided by the Sticky by Tobii team, we plan to screen 1,200 
participants (41% rate of completion) and enroll 500 participants (43% rate of usable 
data).  
Because risk perceptions and behavior intentions are also our primary outcomes, we 
conducted an additional power analysis to calculate the sample size for these two 

outcomes. Based on previous research (e.g., Oschatz & Marker, 2020), narratives had a 
small effect on persuasion. With the alpha level set at .05, we would need at least 800 
participants to detect an effect of d = .20 with 80% power in an independent t-test.  
Given that the sample size to detect a significant effect on risk perceptions and behavior 
intentions (N=800) is larger than that on reactance (N=500), we decided to enroll 800 
participants in our main experiment. Accordingly, we would need to screen 1,951 
participants (41% rate of completion).  
Running the study resulted in 1,045 eligible participants from 1,922 screened 
participants. Of the 1,045 eligible participants, only 404 participants so far completed 
the main experiment successfully. Increasing the screener eligibility to 3,000 is expected 
to increase the successful completion of the main study to the projected 800.  
6.3. Eligibility  
Inclusion criteria: (1) be at least 21 years old; (2) have consumed more than three 
alcoholic drinks per week over the past year; and (3) be willing to participate in remote 
eye tracking tasks and have necessary technical support to complete remote eye 
tracking tasks (i.e., having access to high-speed Internet and a computer/tablet/phone 
equipped with a high-speed camera). 
Exclusion criteria: (1) be younger than 21 years old; (2) has not consumed more than 
three alcoholic drinks per week over the past year; and (3) be not willing to participate 
in remote eye tracking tasks and have necessary technical support to complete remote 
eye tracking tasks (i.e., having access to high-speed Internet and a 
computer/tablet/phone equipped with a high-speed camera). 
We will use a short online screening survey to determine eligibility. A copy of the 
screening survey is included in the submission. The screening data will not be retained 
about individuals who are not enrolled in the research. The screening data will only 
include their Prolific ID, but not other types of identifiers.  
6.4. Vulnerable Populations 
This study will not enroll vulnerable populations.  
6.5. Recruitment Procedures 
We will recruit adult moderate and heavy alcohol users via Prolific, which is an online 
platform to recruit participants. The screening data will not be retained about 
individuals who are not enrolled in the research. The PI, Dr. Zexin Ma, will set up the 
study on Prolific. Participants can send a message to the PI using the built-in messaging 
system on Prolific. When applicable, the PI will also provide her email address to 
participants: zexin.ma@uconn.edu   

A copy of recruitment materials is included in the submission.  
6.6. Consent/Assent Procedures 
After eligible participants sign up for the study, they will be provided with a link to the 
online experiment. At the beginning of the study, participants will be asked to read the 
consent form and click the ‘I accept’ button to proceed. To ensure participants can 
understand the consent, the information will be written at no higher than an eighth-
grade reading level. Participants will also be informed that their decision to participate 
in this study is voluntary. They can choose to stop their participation at any time or skip 
any part of the study if they are not comfortable.  
A copy of the consent form is included in the submission.  
6.7. Costs/Reimbursement 
This study will be conducted online, so there will no costs incurred by subjects as a 
result of participation.  
6.8. Compensation/Incentives  
Study  
Payment per 
participant 
Payment schedule  
Rationales 
Screening survey 
$0.2 
After study completed 
$12 per hour, as 
recommended by Prolific  
Main experiment 
(completed) 
$3 
After study completed 
$12 per hour, as 
recommended by Prolific 
Main experiment 
partial payment  
$0.2  
After participants return 
their submission  
$12 per hour, as 
recommended by Prolific 
Follow-up survey 
$1 
After study completed 
$12 per hour, as 
recommended by Prolific 
 Note: Prolific charges 25% of service fee for each study.  
6.9. Withdrawal/Termination 
Participants can choose to stop their participation at any time. Because this research project 
consists of three parts: the screening survey, the main experiment, and the follow-up 
survey. In the event participants withdrawal after completing one part, their data for the 
completed part will be kept. For example, a participant completes the main experiment but 
not the follow-up survey, their data in the main experiment will be kept.  
Note that Sticky by Tobii (the webcam-based eye-tracking) will report a “terminated” 
category from those that begin the eye-tracking portion of the study. These include 
participants that terminate their participation voluntarily (e.g., close the browser) and 
encounter technical failures (e.g., cannot calibrate). If a participant is terminated by the 
eye-tracking platform, they will not be allowed to complete the rest of the study because 

the remaining questions depend on the stimuli embedded in the eye-tracking task. Thus, 
the terminated participants will be requested to return their submissions. In this case, their 
data will be removed. Given that participants will answer a few questions before they are 
directed to the webcam-based eye-tracking platform, partial payments will be made to 
those who encounter technical failures but not those who withdraw from the study.  
7. Study Procedures 
Given that this project consists of three parts: the screening survey, the main experiment, 
and the follow-up survey; below is a description of each part. No personally identifying 
information will be collected throughout the entire project. Only participants’ Prolific IDs 
will be used to connect data across the three parts.  
The screening survey: Potential participants from the Prolific will first be invited to 
participate in a short online screening survey. The screener will be built using the Qualtrics 
survey platform. We will prescreen the sample to some extent using the Prolific’ existing 
prescreening options, including currently residing in the U.S., being at least 21 years old, 
drinking at least one unit of alcohol on average per week, and having webcam or built-in 
camera that they are willing to use as part of a study. The screening survey will include five 
questions related to their age, average weekly alcohol consumption, and technical support 
to complete eye tracking tasks. Participants must meet the following inclusion criterion to 
be invited to participate in the main experiment: 1) be at least 21 years old; (2) have 
consumed more than three alcoholic drinks per week over the past year; and (3) be willing 
to participate in remote eye tracking tasks and have necessary technical support and 
physical environment to complete remote eye tracking tasks. The entire duration of the 
screening survey is expected to be about 1 minute. 
The main experiment: Eligible participants will be invited to participate in the main 
experiment through the Prolific site. Once they sign up for the main experiment, they will 
be redirected to the online experiment built in Qualtrics survey platform. Participants will 
be first asked to sign the consent form and provided details about the study purpose and 
procedure. They will be informed that they will need to turn on their cameras when 
completing the eye-tracking task. Although their faces and surroundings will be recorded 
during the remote eye-tracking task, the researchers will not have access to these 
recordings. Consented participants will first answer several questions designed to measure 
baseline tobacco and alcohol consumption, alcohol-related knowledge, and the device they 
are currently using to be directed to the corresponding mobile or desktop-based eye-
tracking experiment. Next, participants will engage with a webcam-based eye-tracking task. 
They will first read instructions and tips related to completing the eye-tracking task. They 
will then go through a calibration procedure to ensure good tracking. Participants will then 
be randomly assigned to view an order-randomized stimulus set containing either three 
narrative PWLs or three non-narrative PWLs. Narrative PWLs will contain photos of cancer 

patients, and non-narrative PWLs will include images of diseased organs. All PWLs will 
include a simple, clear warning statement (e.g., “WARNING: Drinking alcohol can cause oral 
cancer.”) to describe the specific cancer risk associated with alcohol. Within each warning 
type, one will focus on oral cancer, one on esophageal cancer, and one on larynx cancer. All 
three cancers have higher relative risks for moderate and heavy drinkers compared to other 
types of cancer linked to alcohol. Participants will be instructed that the image will be 
displayed for 20 seconds and that they need to stay as still as possible while viewing. After 
viewing each PWL, they will proceed to answer questions designed to measure perceived 
attention, reactance, and narrative construction within the eye-tracking platform. After 
viewing all three PWLs, participants will answer additional questions about their and 
affective and cognitive responses toward the warnings, alcohol-related cancer risk 
perceptions and behavioral intentions, and policy support for the warnings. They will then 
answer a few questions designed to collect socio-demographic information at the end of 
the study. Upon completion of the study, participants will be debriefed. They will be 
reminded that they will be invited to participate in a follow-up survey in two weeks. The 
entire duration of the main experiment is expected to be about 15 minutes, with 5 minutes 
spent on completing the eye-tracking portion and 10 minutes on answering questions via 
the Qualtrics survey platform.  
The follow-up survey: Participants who completed the main experiment will be invited to 
participate in the follow-up survey after two weeks. The follow-up survey will include 
questions about their behaviors related to drinking and the labels in the past two weeks. 
Risk perceptions, intentions, and policy support measured in the main experiment will be 
measured again to assess the long-term effect of narrative (vs. non-narrative) PWLs. The 
entire duration of the follow-up survey is expected to be about 5 minutes. 
7.1. Data Collection/Instruments 
The screening survey questionnaire, the main experiment questionnaire, the follow-up 
survey questionnaire, and the experimental stimuli (i.e., narrative and non-narrative PWLs) 
are included in the submission. Below, we briefly describe each questionnaire.  
The screening survey: The screening survey will include five questions related to their age, 
average weekly alcohol consumption, and technical support to complete eye tracking tasks.  
The main experiment: Pre-test measures will assess baseline tobacco and alcohol 
consumption and other alcohol-related background information. Baseline tobacco and 
alcohol consumption are included because the combination of tobacco and alcohol 
significantly increase the risk for developing cancers in mouth, esophagus, and larynx, the 
three cancer types shown in the experimental stimuli. Other alcohol-related background 
information will be included because they may influence how participants respond to the 
experimental stimuli. Post-test measures will assess visual attention measured via the eye-
tracker and a self-report question, avoidance, narrative construction, and reactance in 

response to each PWL, affective and cognitive responses after viewing all PWLs, risk 
perceptions, intentions to reduce and stop drinking, and policy support. The primary 
outcomes include attention, reactance, risk perceptions, and intentions, as stated in the 
hypotheses. The secondary outcomes include avoidance, narrative construction, affective 
and cognitive responses (i.e., processing fluency, affect, cognitive elaboration, and 
retrospective reflection), attitudes toward alcohol, intentions to forgo alcohol, intentions to 
avoid the warnings, and policy support for the warnings. The secondary outcomes are 
measured to explore the underlying psychological mechanisms of narrative (vs. non-
narrative) PWLs. See the attached questionnaire for the self-report questions. Here, we 
describe how attention will be measured with the eye-tracker. Specifically, attention to each 
PWL will be measured with three eye tracking statistics: time until noticed, time viewed, and 
number of visits. Three areas of interest (AOI) will be defined a priori for each PWL, including 
(1) warning image, (2) warning text, and (3) entire warning label. All AOIs are consistent in 
size and location on each stimulus. Time until noticed measures the time between stimulus 
onset and the arrival of the participant’s gaze into a specific AOI, which often reflects an AOI’s 
ability to grab visual attention relative to other elements of a stimulus. Time viewed measures 
the average amount of time spent on an AOI, and it signals attention and cognitive processing. 
Number of visits measures the total number of unique times the AOI was viewed, which is an 
indicator of interest. Finally, socio-demographics will include questions related to their age, 
biological sex, gender identity, ethnicity, race, education, household income, political 
ideology, medical statistics literacy, and cancer history.   
The follow-up survey: The follow-up survey will include questions related to their behaviors 
in the past two weeks, including drinking behavior change due to the labels, information 
seeking behaviors, and social interactions. Risk perceptions, attitudes, intentions, and policy 
support assessed in the main experiment will be measured again in the follow-up survey.  
7.2. Locations/Facilities 
This study will take place online, at a time and place that participants choose. 
8. Risks/Benefits 
8.1. Risks 
Risk 
Probability of 
Risk Occurring  
Magnitude of 
Potential Harm 
Duration of the Risk  
A potential risk is discomfort 
and emotional distress when 
answering questions related 
to alcohol risks and/or viewing 
the experimental materials. 
Occasional 
Minimal 
3-5 minutes when 
participants answer 
questions related to alcohol 
consumption and viewing the 
alcohol warning labels.  

There is also a risk with 
regards to breach of 
confidentiality. 
Rare 
Minimal  
Rare  
There might be risks in 
protecting participants’ 
privacy because their faces 
and surroundings will be 
recorded when engaging in 
the remote, webcam-based 
eye-tracking task. 
Occasional 
Minimal 
2-3 minutes when 
participants engage in the 
webcam-based eye-tracking 
task.  
 
8.2. Risk Mitigation 
Risk 
Strategies for Minimizing Risk  
A potential risk is discomfort and 
emotional distress when answering 
questions related to alcohol risks and/or 
viewing the experimental materials. 
This potential risk can be mitigated by (1) informing 
participants this potential risk in the consent form, (2) 
including a link to the CDC website on alcohol use at 
the end of the survey, and (3) informing participants 
that they have the right to withdraw at any time. 
There might be risks in protecting 
participants’ privacy because their faces 
and surroundings will be recorded when 
engaging in the remote, webcam-based 
eye-tracking task. 
To mitigate this risk, participants will be ensured that 
their recordings will not be accessed by the 
researchers (Note: Tobii is responsible for any 
processing of personal data, and it will not transfer 
any personal data to the researchers.) They will also 
be instructed on where and how to sit in relation to 
the webcam’s recording area. This is to ensure that 
the video capture is limited to those parts (e.g., face, 
head) of the participants that are necessary to 
complete the eye-tracking part. They will also be 
instructed to make sure that no other individuals are 
present for the duration of the study. 
 
8.3. Data Safety Monitoring 
The PI (Dr. Zexin Ma) and her collaborator (Dr. Joshua Haworth) will oversee the progress, 
safety, and data integrity of the trial on an ongoing basis. Adverse events are not anticipated, 
but any occurring will be documented and reported to the UConn and BRANY IRB within three 
business days. A cumulative summary of adverse events and study progress will be 
communicated to the BRANY IRB at continuing review. 
8.4. Benefits 
There may be no direct benefits to participants. Yet, the results of this study may benefit 
others in the future because they will contribute to the scientific understanding of the 
effectiveness of pictorial health warnings.  

 
9. Data/Sample Management, Protection, and Record Keeping 
To protect the confidentiality of the research data, no personal identifying information will 
be collected throughout the project. The screening data will be removed for participants 
who are not enrolled in the main research.  
Because this is an NIIH-funded project, all the study materials and data will be made 
available to the research community in perpetuity free of charge through the Inter-
University Consortium for Political and Social Research (ICPSR). We will use standard 
processing and documentation protocols adopted by the ICPSR for data formats, variable 
names, descriptions, and labels. Datasets will be findable and identifiable through a study 
digital object identifier (DOI) minted by ICPSR. Users of the public use data must register 
with ICPSR and agree to the Terms of Use, which are designed to protect study participants 
by limiting data use to scientific research and aggregate statistical reporting, prohibiting 
attempts to identify study participants, and requiring immediate reporting of any disclosure 
of study participant identity. Data users also agree not to share or redistribute any data 
downloads. Participants will authorize sharing of their de-identified data with other 
researchers through language on the consent form. All data will be de-identified. 
Note that although the study will use webcam-based eye-tracking to measure participants’ 
eye movements, the researchers will not have access to the recordings. The vendor, Sticky 
by Tobii, will be responsible for any processing of personal data, and it will not transfer any 
personal data to the researchers.  
10. Dissemination 
The PI will be responsible for handling ClinicalTrials.gov requirements for this project. I will 
register for the trial at ClinicalTrials.gov no later than 21 days after enrolling the first 
participant. Once a record is established, I will confirm the accuracy of record content, resolve 
problems, and maintain records including content update and modifications. I will also be 
responsible for submitting trial results no later than one year after the primary completion 
date. Informed Consent Documents for the clinical trial will include a specific statement 
relating to posting of clinical trial information at ClinicalTrials.gov.  
This project is expected to produce multiple scientific manuscripts, which will be submitted 
to communication and public health conferences and peer-reviewed journals. Potential 
conference outlets include the annual conference of the International Communication 
Association, National Communication Association, and Society of Behavioral Medicine. 
Potential journal outlets include Human Communication Research, Communication Methods 
and Measures, Health Communication, Journal of Health Communication, Health Education 
& Behavior, American Journal of Public Health, and Social Science & Medicine.   

11. Additional Considerations 
11.1. 
Training and Supervision of Study Personnel 
Besides the PI, there are two personnel on this project. Dr. Joshua Haworth is an expert on 
eye-tracking, and he will work closely with PI for the experiment design, data collection, 
data analysis, and manuscript write-up. Dr. Jun Hu serves as the statistical consultant for 
this project, and he will provide consultancy on the data analysis. Both Drs. Joshua Haworth 
and Jun Hu have the necessary expertise and skills to perform their work.  
11.2. 
Protocol Deviations 
A potential protocol deviation is related to the sample size. As mentioned, we plan to 
screen 1,200 participants and enroll 500 participants for the main study. If we do not have 
500 eligible participants signed up for the main study after screening 1,200 participants, we 
will need to continue the screening study. Similarly, if we do not have 213 completed 
participants to achieve a statistical power of .80, we will also need to continue the screening 
study and enroll more participants in the main experiment. In addition, if participant 
demographic distribution does not approximate the demographics of the general 
population in the United States (e.g., not enough racial minority participants), we will 
recruit participants from the specific populations on Prolific for the screening survey and 
the main study until the sample approximates the U.S. demographics. We will report the 
protocol deviations to the BRANY IRB following their policies and procedures. 
Another potential deviation is related to the experiment stimuli. The stylistic design of the 
PWLs may be changed, such as adding a boarder to each PWL or using a black background 
and white text (the current version uses a white background and black text). However, the 
content of the image and text will remain the same.  
11.3. 
Unanticipated Problems 
An unanticipated problem could be an actual breach of participants study information. 
When this unanticipated problem occurs, we will report it to the BRANY IRB following their 
policies and procedures.