An interventional study of Label with text health warning and Label with pictorial health warning in Vaping Behaviors, sponsored by UNC Lineberger Comprehensive Cancer Center. Completed at 1 site in United States. Open to participants aged 21 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-09-12.
Sponsored by UNC Lineberger Comprehensive Cancer Center · Not applicable, Interventional, and Prevention
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.
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.
160 studies on the registry are indexed under Vaping; 72 are open to participants now.
This study's enrollment of 1,369 is above the median of 110 across 135 interventional studies indexed under Vaping.
Browse Vaping studies →UNC Lineberger Comprehensive Cancer Center is the lead sponsor of 414 studies on the registry; 96 are open to participants now.
Of its 32 completed or terminated interventional studies of FDA-regulated products, 25 (78%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
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 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 neutral statements about vaping will be applied to participants' vaping devices and refills.
Other: Label with neutral statements about vaping
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.
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.
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.
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.
Time frame: Up to 4 weeks
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).
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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).
Time frame: 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).
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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).
Time frame: Up to 4 weeks
| Milestone | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Started | 456 | 457 | 456 |
| Completed | 454 | 452 | 452 |
| Not completed | 2 | 5 | 4 |
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.
| score on a scale | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Vaping Quit Intentions Score | 2.5 ± 1.3 | 2.5 ± 1.1 | 2.2 ± 1.0 |
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).
| score on a scale | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Knowledge Score | 0.6 ± 0.3 | 0.6 ± 0.3 | 0.4 ± 0.3 |
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.
| score on a scale | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Cognitive Elaboration Score | 2.7 ± 0.9 | 2.9 ± 0.9 | 2.0 ± 0.8 |
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.
| score on a scale | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Perceived Likelihood of Illness Score | 3.1 ± 0.8 | 3.1 ± 0.8 | 2.9 ± 0.9 |
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.
| score on a scale | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Negative Affect Score | 2.1 ± 0.9 | 2.3 ± 1.0 | 1.4 ± 0.6 |
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.
| score on a scale | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Attention Score | 3.1 ± 0.9 | 3.3 ± 0.9 | 2.8 ± 0.9 |
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.
| number of times sought information | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Information Seeking Score | 1.3 ± 1.3 | 1.4 ± 1.3 | 0.8 ± 1.0 |
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.
| number of conversations | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Number of Conversations in Past Week | 1.5 ± 2.2 | 1.7 ± 2.1 | 1.2 ± 1.8 |
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.
| units on a scale | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Vaping Reinforcement Attitudes Score | 4.1 ± 0.8 | 4.1 ± 0.8 | 4.2 ± 0.8 |
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.
| score on a scale | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Uncontrolled Vaping Score | 2.4 ± 0.9 | 2.4 ± 1.0 | 2.3 ± 1.0 |
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.
| number of times forgoing a vape | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Number of Times Forgoing a Vape in Past Week | 1.7 ± 1.6 | 1.7 ± 1.5 | 1.3 ± 1.4 |
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).
| Participants | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Percent of Participants Who Made a Vaping Quit Attempt in Past 4 Weeks | 217 | 204 | 211 |
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).
| percentage of participants | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Percent of Participants Who Successfully Quit Vaping | 7.2 | 7.4 | 3.7 |
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.
| proportion of correct answers | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Inaccurate Risk Perception Score | 0.42 ± 0.42 | 0.44 ± 0.43 | 0.48 ± 0.43 |
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.
| score on a scale | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Stigma Score | 1.9 ± 0.8 | 2.0 ± 0.9 | 1.6 ± 0.7 |
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.
| score on a scale | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Mean Smoking Quit Intentions Score | 2.4 ± 0.9 | 2.5 ± 0.9 | 2.3 ± 0.9 |
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).
| percentage of participants | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping |
|---|---|---|---|
| Percent of Participants Who Made a Smoking Quit Attempt in Past 4 Weeks | 54.3 | 67.9 | 63.1 |
Collected over From the time of signing informed consent, through study completion, a total of up to 4 weeks.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Label With Text Health Warning | 0/456 (0%) | 0/456 (0%) | 0/456 (0%) |
| Label With Pictorial Health Warning | 0/457 (0%) | 0/457 (0%) | 0/457 (0%) |
| Label With Neutral Statements About Vaping | 0/456 (0%) | 0/456 (0%) | 0/456 (0%) |
| Age, Customized(Participants) | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping | Total |
|---|---|---|---|---|
| 21-29 years | 133 | 130 | 141 | 404 |
| 30-39 years | 170 | 159 | 166 | 495 |
| 40-49 years | 100 | 100 | 95 | 295 |
| 50+ years | 53 | 68 | 54 | 175 |
| Sex/Gender, Customized(Participants) | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping | Total |
|---|---|---|---|---|
| Female | 193 | 197 | 208 | 598 |
| Male | 249 | 237 | 221 | 707 |
| Nonbinary/Another gender | 14 | 23 | 27 | 64 |
| Race/Ethnicity, Customized(Participants) | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping | Total |
|---|---|---|---|---|
| American Indian or Alaskan Native | 5 | 4 | 3 | 12 |
| Asian | 54 | 25 | 39 | 118 |
| Black or African American | 78 | 77 | 74 | 229 |
| Hispanic | 32 | 51 | 46 | 129 |
| Middle Eastern or North African | 2 | 8 | 2 | 12 |
| Native Hawaiian or other Pacific Islander | 1 | 4 | 3 | 8 |
| White | 194 | 196 | 183 | 573 |
| Multiracial or another race or ethnicity | 90 | 91 | 106 | 287 |
| Missing | 0 | 1 | 0 | 1 |
| Region of Enrollment(participants) | Label With Text Health Warning | Label With Pictorial Health Warning | Label With Neutral Statements About Vaping | Total |
|---|---|---|---|---|
| United States | 456 | 457 | 456 | 1369 |
Documents are hosted by the registry — open the source record to download them.
Plan to share: Yes — 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.
Supporting information: Sap, Analytic code
This study is completed, as verified in Aug 2025. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
UNC Lineberger Comprehensive Cancer Center