Impact of E-cigarette Device Warnings

Randomized Clinical Trial Evaluating the Impact of E-cigarette Device Warnings

The purpose of this randomized clinical trial is to determine whether e-cigarette warnings increase intentions to quit vaping without the unintended consequence of pushing users toward smoking. This trial addresses these issues by evaluating the impact of e-cigarette warnings by randomly assigning vapers to have their devices and refills labeled with control messages, text warnings, or pictorial warnings. Participants will be US adult (ages 21+) vapers. The trial expects ~1,200 participants to complete Visits 1, 3, and 5.

Study Overview

• Status: Completed
• Conditions: Vaping Behaviors
• Intervention / Treatment: Other: Label with text health warning; Other: Label with pictorial health warning; Other: Label with neutral statements about vaping

Detailed Description

This trial will assess the impact of e-cigarette warnings on vapers' devices and refills in a randomized clinical trial.

Recruitment: Vapers will first undergo screening online or call the study center to complete the screening survey over the phone. Trial staff will schedule eligible vapers for 2 in-person visits. For each of the 2 visits, vapers will be asked to bring the vapes and refill materials they plan to use over the next 2 weeks.

Informed Consent: Prior to consenting vapers, trial staff will visually inspect photo identification of vapers to confirm that they are 21 years or older. At the beginning of the first appointment, trial staff will explain the consent form and ask the vaper to read the form. Once the participant has finished reading the form, the trial staff member will ask the participant if he or she has any questions. Then both parties will sign the consent form and the participant will receive a copy of the consent form.

Randomization: At the first visit, trial staff will randomly assign participants to one of the three trial arms by using Qualtrics software. Vapers have an equal chance of being randomized to have labels with control, text, or pictorial warnings.

Assessment: Participants will attend 2 in-person appointments at the study office (at Visit 1 and Visit 3 that are spaced 2 weeks apart). The visits will last about 45-60 minutes. At Visit 1 participants will take a survey, have their vape device and refills labeled based on their trial arm, and take another survey. At Visit 3, participants take a survey and have their vape device and refills labeled based on their trial arm. Participants will also be e-mailed 3 more surveys to complete online at home (taken at Visit 2, 4, and 5). Thus participants will take 5 weekly surveys overall.

Detailed description of the intervention: At each in-person appointment, participants will bring in the vapes and refills they plan to use over the next 2 weeks for labeling. While participants are taking the survey, trial staff will label the devices and refills based on their trial arm.

Participants randomized to the text warning arm will have labels with information about the health harms of vaping applied to their vapes and refills. Participants randomized to the pictorial arm will have labels with pictorial images and text about the health harms of vaping. Participants assigned to the control arm will have labels with neutral statements about vaping. Each trial arm will have four labels (two labels for Visit 1 and two additional labels for Visit 3). Trial staff will return labeled vapes and refills in a clear plastic bag with the e-cigarette warning labels applied to a card. Trial investigators developed the text, images, and design of these labels.

The trial staff will instruct participants in all trial arms to vape or not vape as they normally would. At the end of the trial, participants will receive a link to more information about the risks of vaping and tobacco use.

• Study Type: Interventional
• Enrollment (Actual): 1369
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • San Francisco, California, United States, 94104
      • Ewald & Wasserman Research Consultants, LLC

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Be 21 years or older
• Currently vape every day or some days
• Use an e-cigarette that contains nicotine
• Be able to attend 2 in-person appointments
• Be able to bring in e-cigarette device and 2 weeks' worth or refills to 2 in-person appointments
• Be willing to let us apply a sticker to the device and refill materials
• Be willing to use only the labeled e-cigarette during the study
• Be able to complete 3 surveys online at home
• Be able to read and speak English
• Be able to complete a survey on a computer without help

Exclusion Criteria:

• Pregnant people
• If e-cigarette device cannot be labeled
• Vapers concurrently enrolled in any research studies about vaping or using other tobacco products
• Vapers who live in the same household as someone who has enrolled in the study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Label with text health warning; Labels with e-cigarette health warning that include text about health harms of vaping will be applied to participants' vaping devices and refills.	Other: Label with text health warning; Labels with e-cigarette health warning that include text about health harms of vaping will be applied to participants' vaping devices and refills. At Visit 1, devices and refills will be labeled with 2 warnings based on their assigned trial arm; at Visit 3, they will get 2 additional warnings based on their assigned trial arm. The order of the 4 labels within this trial arm will be randomized using a Latin square design. Study investigators developed the text and design of these labels.
Experimental: Label with pictorial health warning; Labels with e-cigarette health warning that include the same text about health harms of vaping and corresponding pictorial images will be applied to participants' vaping devices and refills.	Other: Label with pictorial health warning; Labels with e-cigarette health warning that include the same text about health harms of vaping and corresponding pictorial images will be applied to participants' vaping devices and refills. At Visit 1, devices and refills will be labeled with 2 warnings based on their assigned trial arm; at Visit 3, they will get 2 additional warnings based on their assigned trial arm. The order of the 4 labels within this trial arm will be randomized using a Latin square design. Study investigators developed the text and design of these labels.
Other: Label with neutral statements about vaping; Labels with neutral statements about vaping will be applied to participants' vaping devices and refills.	Other: Label with neutral statements about vaping; Labels with neutral statements about vaping will be applied to participants' vaping devices and refills. At Visit 1, devices and refills will be labeled with 2 statements based on their assigned trial arm; at Visit 3, they will get 2 additional statements based on their assigned trial arm. The order of the 4 labels within this trial arm will be randomized using a Latin square design. Study investigators developed the text and design of these labels.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Vaping Quit Intentions Score	The primary outcome is vaping quit intentions measured by 3 survey items at 5 time points: post-labeling (Visit 1) and at 1, 2, 3, and 4 weeks (Visits 2-5). Study investigators will average the items to create a score for each time point and take an average across the time points. The range for this measure will be 1 to 5, with higher values indicating higher quit intentions.	Up to 4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Knowledge Score	Knowledge of health harms from vaping will be measured by 5 survey items at 5 time points: post-labeling (Visit 1) and at 1, 2, 3, and 4 weeks (Visits 2-5). Study investigators will score each item for accuracy (correct or incorrect) and average the scores (% correct) for each time point and take an average across the time points. The range for this measure will be 0% to 100%, with higher values indicating more accurate knowledge).	Up to 4 weeks
Mean Cognitive Elaboration Score	Cognitive elaboration (thinking about the label) will be measured by 3 survey items at 4 time points: 1, 2, 3, and 4 weeks (Visits 2-5). Study investigators will average the items to create a score for each time point and take an average across the time points. The range for this measure will be 1 to 5, with higher values indicating more cognitive elaboration.	Up to 4 weeks
Mean Perceived Likelihood of Illness Score	Perceived likelihood of illness from vaping will be measured by 3 survey items at 5 time points: post-labeling (Visit 1) and at 1, 2, 3, and 4 weeks (Visit 2-5). Study investigators will average the items to create a score for each time point and take an average across the time points. The range for this measure will be 1 to 5, with higher values indicating higher perceived likelihood.	Up to 4 weeks
Mean Negative Affect Score	Negative affective reactions to the labels will be measured by 5 survey items at 5 time points: post-labeling (Visit 1) and at 1, 2, 3, and 4 weeks (Visits 2-5). Study investigators will average the items to create a score for each time point and take an average across the time points. The range for this measure will be 1 to 5, with higher values indicating more negative affect.	Up to 4 weeks
Mean Attention Score	Attention to the labels will be measured by 3 survey items at 4 time points: 1, 2, 3, and 4 weeks (Visits 2-5). Study investigators will average the items to create a score for each time point and take an average across the time points. The range for this measure will be 1 to 5, with higher values indicating greater attention.	Up to 4 weeks
Mean Information Seeking Score	Information seeking about the harms of vaping will be measured by 1 survey item at 4 time points: 1, 2, 3, and 4 weeks (Visits 2-5). Study investigators will score responses (0 times=0, 1-2 times=1.5, 3-5 times=4, 6+ times=6) and take an average across the time points. The range for this measure will be 0 times to 6 times), with higher values indicating more information seeking.	Up to 4 weeks
Mean Number of Conversations in Past Week	Number of conversations with others about the labels, health harms caused by vaping, and quitting vaping will be measured by 3 survey items at 4 time points: 1, 2, 3, and 4 weeks (Visits 2-5). Study investigators will average the items to create a score for each time point and take an average across the time points. The range for this measure will be 0 times to 100 times, with higher values indicating more conversations.	Up to 4 weeks
Mean Vaping Reinforcement Attitudes Score	Positive vaping reinforcement attitudes will be measured by 3 survey items at 5 time points: post-labeling (Visit 1) and at 1, 2, 3, and 4 weeks (Visits 2-5). We will take an average across the time points. The range for this measure will be 1 to 5, with higher values indicating more positive vaping reinforcement attitudes.	Up to 4 weeks
Mean Uncontrolled Vaping Score	Subjective uncontrolled vaping (vaping more than the user prefers) will be measured by 3 survey items at 4 time points: 1, 2, 3, and 4 weeks (Visit 2-5). Study investigators will average the items to create a score for each time point and take an average across the time points. The range for this measure will be 1 to 5, with higher values indicating vaping that is more uncontrolled.	Up to 4 weeks
Mean Number of Times Forgoing a Vape in Past Week	Number of times forgoing a vape in the last week will be measured by 4 survey items at 4 time points: 1, 2, 3, and 4 weeks (Visits 2-5). Study investigators will score responses (never=0, 1 time=1, 2 times=2, 3-5 times=4, 6+ times=6), average the items to create a score for each time point, and take an average across the time points. The range for this measure will be 0 times to 6 times, with higher values indicating more forgoing.	Up to 4 weeks
Percent of Participants Who Made a Vaping Quit Attempt in Past 4 Weeks	Made vaping quit attempt will be measured by 1 survey item (not vaping for 1 day or longer in the last week because they were trying to stop vaping) at 4 time points: 1, 2, 3, and 4 weeks (Visits 2-5). There will be an additional item (not vaping for 1 day or longer since the start of the study) at 4 weeks (Visit 5). Study investigators will score the items for any quit attempts: 0 (no quit attempts) or 1 (one or more quit attempt across the 4 weeks).	Up to 4 weeks
Percent of Participants Who Successfully Quit Vaping	Successful quitting of vaping during the trial will be measured by 1 survey item at 1 time point (participants' last survey, usually Visit 5). Study investigators will score the item for successful quitting: 0 (vaping on one or more of the last 7 days) or 1 (no vaping).	At 4 weeks
Mean Inaccurate Risk Perception Score	Inaccurate risk perception of vaping (believing vaping is the same or more harmful than smoking cigarettes) will be measured by 1 survey item at 5 time points: post-labeling (Visit 1) and 1, 2, 3, and 4 weeks (Visits 2-5). Study investigators will score the item for accuracy (vaping less harmful than smoking cigarettes=correct; other answers=incorrect) and take an average across the time points. The range for this measure will be 0% (no correct answers) to 100% (all correct answers), with higher values indicating more accurate risk perceptions.	Up to 4 weeks
Mean Stigma Score	Stigma (expecting the labels will cause social disapproval of vaping) will be measured by 3 survey items at 5 time points: post-labeling (Visit 1) and at 1, 2, 3, and 4 weeks (Visits 2-5). Study investigators will average the items to create a score for each time point and take an average across the time points. The range for this measure will be 1 to 5, with higher values indicating more stigma.	Up to 4 weeks
Mean Smoking Quit Intentions Score	Smoking quit intentions will be measured by 3 survey items at 5 time points: post-labeling (Visit 1) and 1, 2, 3, and 4 weeks (Visits 2-5). Study investigators will average the items to create a score for each time point and take an average across the time points. The construct will be assessed only among cigarette smokers. The range for this measure will be 1 to 5, with higher values indicating higher intentions.	Up to 4 weeks
Percent of Participants Who Made a Smoking Quit Attempt in Past 4 Weeks	Made smoking quit attempt will be measured by 1 survey item (not smoking for 1 day or longer in the last week because they were trying to stop smoking) at 4 time points: 1, 2, 3, and 4 weeks (Visits 2-5). There will be an additional item (not smoking for 1 day or longer since the start of the study) at 4 weeks (Visit 5). Study investigators will score the items for any quit attempts: 0 (no quit attempts) or 1 (at least one quit attempt across the 4 weeks).	Up to 4 weeks

Collaborators and Investigators

• Sponsor: UNC Lineberger Comprehensive Cancer Center
• Collaborators: National Institute on Drug Abuse (NIDA)
• Investigators: Principal Investigator: Noel Brewer, PhD, University of North Carolina, Chapel Hill

Study record dates

Study Major Dates

• Study Start (Actual): February 23, 2023
• Primary Completion (Actual): July 23, 2024
• Study Completion (Actual): July 23, 2024

Study Registration Dates

• First Submitted: January 24, 2023
• First Submitted That Met QC Criteria: February 2, 2023
• First Posted (Actual): February 6, 2023

Study Record Updates

• Last Update Posted (Estimated): September 12, 2025
• Last Update Submitted That Met QC Criteria: August 22, 2025
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Keywords: Vaping; Tobacco use; E-cigarette use
• Additional Relevant MeSH Terms: Behavior; Smoking; Vaping; Tobacco Use; Technology, Industry, and Agriculture; Industry; Product Packaging; Product Labeling
• Other Study ID Numbers: 21-0469; R01DA048390 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The trial investigators will produce a de-identified dataset and codebook for sharing with external investigators, making use of the UNC Dataverse digital data repository (dataverse.unc.edu) hosted by the Odum Institute Data Archive.
• IPD Sharing Time Frame: The data will be available beginning 12 to 36 months following the primary publication.
• IPD Sharing Access Criteria: To obtain a copy of the dataset and codebook, a research scientist will have to submit a request in writing, identifying themselves and their affiliated institution, indicating what they plan to do with the data, and including assurances that they will not share the data with others without the written permission of the PI. Requestors must already have institutional review board, independent ethics committee, or research ethics board approval as applicable. Requestors must obtain a data use agreement through UNC's Office of Industry Contracting (OIC@unc.edu) to receive the dataset and codebook and agree to acknowledge NIH and the study investigators in any publications resulting from the data.
• IPD Sharing Supporting Information Type: SAP; ANALYTIC_CODE

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No