An interventional study of Preferred ENDS and Preferred ENDS with HWL in Electronic Cigarette Use, sponsored by Florida International University. Recruiting at 1 site in United States. Open to participants aged 21 Years to 35 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-06-05.
Sponsored by Florida International University · Not applicable, Interventional, and Prevention
In this project, after systematically developing electronic nicotine delivery systems (ENDS) pictorial health warning labels (HWLs), a proven clinical lab model will be used to examine and test their effect when these are placed on the ENDS device on a variety of subjective (e.g. satisfaction, harm perception, nicotine dependence, intention to quit) and objective outcomes (e.g. plasma nicotine, puff topography) in young adults.
The use of electronic nicotine delivery systems (ENDS or e-cigarettes) has reached epidemic levels among young people in the United States (US). ENDS emit toxic substances, including nicotine that irreversibly affects youth's developing brain leading to dependence and increased risk of cigarette smoking initiation, yet misperceptions about their safety are widespread. Therefore, health communication of ENDS-related risks through Health Warning Labels (HWLs) has been considered as a priority by leading health and regulatory bodies in the US to reduce ENDS use among young people. The FIU Epidemiology Clinical Tobacco Research Lab has developed and pilot-tested a clinical lab model to examine the potential effects of pictorial HWLs on young (21-29 yrs) ENDS users' experiences. In this proposal, this model, coupled with a systematic development of ENDS pictorial HWLs, will be used to test their effect when they are placed on the device on a variety of subjective (e.g. satisfaction, harm perception, nicotine dependence, intention to quit) and objective outcomes (e.g. plasma nicotine, puff topography). This will be done in three stages. First, the literature will be reviewed to develop candidate messages and their associated pictures for the HWLs. This initial set of HWLs will then be revised and ranked through a Delphi study among tobacco control, regulation, and health communication experts. Second, focus groups with young ENDS (21-29 yrs) users will be conducted to adapt the candidate HWLs to our target population and device itself. Third, HWLs on the ENDS device will be tested in a clinical lab cross-over study, where each subject uses ENDS in 2 sessions; 1) their preferred product without HWL (control), and 2) their preferred product with pictorial HWL on the ENDS device. This design will test our main hypothesis; compared to control, using ENDS with the HWLs is associated with decreased satisfaction, dependence suppression, and puffing behavior, but increased knowledge about harm and intention to quit. This project will guide policymakers into the application of effective HWLs for ENDS and will develop warning messages and pictorials that national and state stakeholders can use through different modalities in counter-marketing campaigns to protect young people and discourage harmful ENDS use.
402 studies on the registry are indexed under Vaping; 95 are open to participants now.
This study's planned enrollment of 80 is close to the median of 79 across 322 interventional studies indexed under Vaping.
Browse Vaping studies →Florida International University is the lead sponsor of 104 studies on the registry; 20 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
All participants will complete a lab visit where they will use their preferred ENDS ad libitum for up to 60 minutes
Other: Preferred ENDS · Other: Preferred ENDS with HWL
All participants will complete a lab visit where they will use their preferred ENDS with a HWL on the device ad libitum for up to 60 minutes
Other: Preferred ENDS · Other: Preferred ENDS with HWL
Preferred ENDS without HWL on device
Preferred ENDS with a HWL on device
Plasma nicotine
Change in plasma nicotine level
Time frame: During the 2 participant visits. Blood will be taken 2 times in each ENDS use session: before and after an approximately 60-min ad lib use period
Puff topography
Measurement of puffing behavior
Time frame: Time Frame: During participants' two study visits. Puffing behavior is continuously measured during each ENDS use session (an approximately 60-min ad lib use period)
Minnesota Nicotine Withdrawal Scale
This scale is used to assess the extent to which product use reduces tobacco abstinence symptoms, and consists of 11 items scored 0 - 100. These items are presented as Visual Analog Scale with item (measure) centered above a horizontal line anchored on the left with not at all and on the right with extremely.
Time frame: During participants' 2 study visits. Questionnaire will be administered 2 times in each ENDS use session: before and after an approximately 60-min ad lib use period
Tiffany-Drobes Questionnaire of Smoking Urges
This scale is used to assess the extent to which product use reduces tobacco abstinence symptoms, and consists of 10 items that are scored 0 - 7. Rated on a 7-point Likert scale ranging from 0 (strongly disagree) to 6 (strongly agree).
Time frame: During participants' two study visits. Questionnaire will be administered 2 times in each ENDS use session: before and after an approximately 60-min ad lib use period.
Carbon monoxide levels
Change in carbon monoxide levels (in parts per million)
Time frame: During participants' two study visits. Carbon monoxide levels will be measured 2 times in each ENDS use session: before and after an approximately 60-min ad lib use period
Harm perception
This scale will assess waterpipe harm perception and measure perceptions of waterpipe relative risk compared to cigarettes. The scale will be scored on a 7-point scale ranging from 1 (not at all harmful), to 7 (extremely harmful).
Time frame: During participants' two study visits. Questionnaire will be administered after each of the 2 ENDS use sessions. Each session is approximately 60-min ad lib use period.
Duke Sensory Questionnaire
This scale will assess participants sensory experience of the inhaled product. The scale has nine items. All items will be scored on a 7-point Likert scale anchored at the extremes (1= not at all; 7=extremely).
Time frame: During participants' two study visits. Questionnaire will be administered after each of the 2 ENDS use sessions. Each session is approximately 60-min ad lib use period.
The Cigarette/ENDS Evaluation Scale (WES)
This scale assesses participants' perception of ENDS use. The scale has 11 items. All items will be scored on a 7-point Likert scale anchored at the extremes (1= not at all; 7=extremely).
Time frame: During participants' two study visits. Questionnaire will be administered after each of the 2 ENDS use sessions. Each session is approximately 60-min ad lib use period.
Forced expiratory volume (FEV1)
Forced expiratory volume (FEV) measures how much air a person can exhale during a forced breath.FEV is used to measure lung function.
Time frame: During participants' 2 study visits. FEV tests will be measured 2 times in each e-cigarette use session: before and after an approximately 60 minutes ad lib use period
Forced vital capacity (FVC)
Forced vital capacity (FVC) is the maximum amount of air that can be exhaled when blowing out as fast as possible FVC is used to measure lung function.
Time frame: During participants' 2 study visits. FVC tests will be measured 2 times in each e-cigarette use session: before and after an approximately 60 minutes ad lib use period
Peak expiratory flow (PEF)
Peak expiratory flow (PEF) is the maximal flow that can be exhaled when blowing out at a steady rate. PEF is used to measure lung function.
Time frame: During participants' 2 study visits. PEF tests will be measured 2 times in each e-cigarette use session: before and after an approximately 60 minutes ad lib use period
Forced expiratory flow
Forced expiratory flow, also known as mid-expiratory flow; the rates at 25%, 50% and 75% FVC are given. Forced expiratory flowis used to measure lung function.
Time frame: During participants' 2 study visits. Forced expiratory flow tests will be measured 2 times in each e-cigarette use session: before and after an approximately 60 minutes ad lib use period
Heart rate
Change in heart rate, measured in beats per minute
Time frame: During participants' two study visits. Heat rate will be measured from baseline continuously throughout each approximately 60-min session.
Blood pressure
Change in blood pressure, measured in mm/hg
Time frame: During participants' two study visits. Blood pressure will be measured from baseline continuously throughout each approximately 60-min session
Plan to share: No
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Started Dec 2023 (actual). Primary completion is estimated for Dec 2026, 36 months after the start.
Of 184 non-industry interventional studies with no phase under Vaping, half reached primary completion within 20 months of starting (the median), counting those still running; a quarter within 9 and three quarters within 35. This study's planned 36 months is above that.
Counting every sponsor, half of 208 studies reached it within 18 months; a quarter within 6 and three quarters within 31.
How these figures are worked out, and which studies are left out of them.
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