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Completed

NCT Number: NCT05714982

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.

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Key information

Age range

21 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Ewald & Wasserman Research Consultants, LLC

San Francisco, California, 94104, United States

About this study

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.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

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

Treatment and study plan

Label with text health warning

Other

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.

Label with pictorial health warning

Other

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.

Label with neutral statements about vaping

Other

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.

Primary outcomes

  1. Mean Vaping Quit Intentions Score

    Time frame: Up to 4 weeks

    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.

Secondary outcomes

  1. Mean Knowledge Score

    Time frame: Up to 4 weeks

    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).

  2. Mean Cognitive Elaboration Score

    Time frame: Up to 4 weeks

    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.

  3. Mean Perceived Likelihood of Illness Score

    Time frame: Up to 4 weeks

    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.

  4. Mean Negative Affect Score

    Time frame: Up to 4 weeks

    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.

  5. Mean Attention Score

    Time frame: Up to 4 weeks

    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.

  6. Mean Information Seeking Score

    Time frame: Up to 4 weeks

    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.

  7. Mean Number of Conversations in Past Week

    Time frame: Up to 4 weeks

    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.

  8. Mean Vaping Reinforcement Attitudes Score

    Time frame: Up to 4 weeks

    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.

  9. Mean Uncontrolled Vaping Score

    Time frame: Up to 4 weeks

    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.

  10. Mean Number of Times Forgoing a Vape in Past Week

    Time frame: Up to 4 weeks

    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.

  11. Percent of Participants Who Made a Vaping Quit Attempt in Past 4 Weeks

    Time frame: Up to 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).

  12. Percent of Participants Who Successfully Quit Vaping

    Time frame: At 4 weeks

    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).

  13. Mean Inaccurate Risk Perception Score

    Time frame: Up to 4 weeks

    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.

  14. Mean Stigma Score

    Time frame: Up to 4 weeks

    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.

  15. Mean Smoking Quit Intentions Score

    Time frame: Up to 4 weeks

    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.

  16. Percent of Participants Who Made a Smoking Quit Attempt in Past 4 Weeks

    Time frame: Up to 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).

Sponsors and collaborators

Lead sponsor

UNC Lineberger Comprehensive Cancer Center

Other

Collaborators

  • National Institute on Drug Abuse (NIDA)

Registry information

Official study title

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

Important dates

Study start
2023
Primary completion
2024
Study completion
2024
First posted
Feb 6, 2023
Registry last updated
Sep 12, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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