Influencer Marketing and Adolescent E-cigarette Use

February 11, 2026 updated by: Jennifer Unger, University of Southern California

The Effect of Social Media Influencer Marketing on E-cigarette Perceptions and Use by Adolescents.

Adolescents (N = 700) participated in the online survey-based randomized experiment focused on understanding youth perceptions of e-cigarette influencer marketing on social media. Specifically, the study assessed how age appearance of social media influencers, fitness-related contextual framing of e-cigarette content, and perceived influencer credibility jointly shape adolescent harm perceptions, appeal, and susceptibility to e-cigarette use. Participants were randomly shown 6 videos, featuring younger- or older-looking influencers promoting e-cigarettes in the following experimental conditions: 1) younger-looking influencers promoting e-cigarettes alongside fitness-oriented activities (condition 1); 2) older-looking influencers promoting e-cigarettes alongside fitness-oriented activities (condition 2); 3) younger-looking influencers promoting e-cigarettes without any fitness-oriented content; and 4) older-looking influencers promoting e-cigarettes without any fitness-oriented content (control). After watching each video, participants rated perceptions of influencer credibility (i.e., honesty, trustworthiness, knowledge) on the scale of 0 (e.g., dishonest) to 100 (honest). Among all participants, harm perceptions and appeal of e-cigarettes was also assessed. Susceptibility to use e-cigarettes was assessed among never users of e-cigarettes.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Adolescents (14-17 years of age) living in California were recruited by Qualtrics marketing research panel to participate in a survey on tobacco-related attitudes and behaviors. Qualtrics, a research panel agency, has been used in prior research to survey adolescents about their tobacco-related attitudes and behaviors. Participants were provided with a survey URL link. After completing informed consent, participants completed the survey online. The study was approved by the University of Southern California Institutional Review Board (UP-CG-24-00013). Respondents were randomly assigned to watch six 10-second long Instagram and/or TikTok videos in four experimental conditions: 1) younger-looking influencers promoting e-cigarettes alongside fitness-oriented activities (condition 1); 2) older-looking influencers promoting e-cigarettes alongside fitness-oriented activities (condition 2); 3) younger-looking influencers promoting e-cigarettes without any fitness-oriented content; and 4) older-looking influencers promoting e-cigarettes without any fitness-oriented content (control).

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
700

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Washington
      • Seattle, Washington, United States, 98101
        • Qualtrics, survey was administered online

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Child

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • 14-17 years of age,
  • English fluency,
  • Current California resident.

Exclusion Criteria:

Not meeting the following criteria:

  • 14-17 years of age,
  • English fluency,
  • Current California resident.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Other
  • Allocation: Randomized
  • Interventional Model: Factorial Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Videos featuring young influencers promoting e-cigarettes alongside fitness-related activities
a 10 second video clip
Other: Youth Perceptions of Influencer Age and Fitness Contexts in E-Cigarette Marketing
Participants watched online survey-imbedded promotional videos featuring influencers. Influencer age appearance was manipulated using AI-based age filter.
Experimental: Videos featuring older influencers promoting e-cigarettes alongside fitness-related activities
a 10 second video clip
Other: Youth Perceptions of Influencer Age and Fitness Contexts in E-Cigarette Marketing
Participants watched online survey-imbedded promotional videos featuring influencers. Influencer age appearance was manipulated using AI-based age filter.
Experimental: Videos featuring young influencers promoting e-cigarettes without fitness-related activities
a 10 second video clip
Other: Youth Perceptions of Influencer Age and Fitness Contexts in E-Cigarette Marketing
Participants watched online survey-imbedded promotional videos featuring influencers. Influencer age appearance was manipulated using AI-based age filter.
Active Comparator: Videos featuring older influencers promoting e-cigarettes without fitness-related activities
a 10 second video clip
Other: Youth Perceptions of Influencer Age and Fitness Contexts in E-Cigarette Marketing
Participants watched online survey-imbedded promotional videos featuring influencers. Influencer age appearance was manipulated using AI-based age filter.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Harm Perceptions of e-cigarettes
Time Frame: assessed six times immediately after each of the six videos during the 15-minute-long survey-based experiment
Responses to one question adapted from PATH, "Based on the videos you just watched, do you think using e-cigarettes for vaping nicotine is harmful to your health?" The outcome was assessed on the 5-point ordinal scale with the following response choices: Not at all harmful, slightly harmful, somewhat harmful, very harmful, extremely harmful.
assessed six times immediately after each of the six videos during the 15-minute-long survey-based experiment
Perceived appeal of e-cigarettes
Time Frame: Assessed six times immediately after each of the six videos during the 15-minute-long survey-based experiment
Description: Responses to the following questions: using e-cigarette is: not cool/cool, unattractive/attractive were assessed on the 7-point semantic differential scale with the word pairs anchored at each end. The scale was adapted from prior research. The items were combined (by summing all the non-missing values of the items) into one variable (α=0.94).
Assessed six times immediately after each of the six videos during the 15-minute-long survey-based experiment
Susceptibility to e-cigarette use
Time Frame: Assessed six times immediately after each of the six videos during the 15-minute-long survey-based experiment
Susceptibility to e-cigarette use was measured (among never-users of e-cigarettes), using the validated three-item scale (indicating peer influence, intention, and curiosity about e-cigarette use) adapted from PATH, and combined into one variable (α=0.93). Consistent with prior research, the measure was dichotomized with responses "definitely not" to all items being coded as "not susceptible" and responses "probably not," "probably yes", or "definitely yes" being coded as "susceptible."
Assessed six times immediately after each of the six videos during the 15-minute-long survey-based experiment
Perceived influencer credibility
Time Frame: Assessed six times immediately after each of the six videos during the 15-minute-long survey-based experiment
Perceived influencer credibility (i.e., honesty, trustworthiness, knowledge) were assessed using a 0 (e.g., dishonest) -100 (e.g., honest) scale that has been validated in prior research.
Assessed six times immediately after each of the six videos during the 15-minute-long survey-based experiment

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Southern California

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Tobacco Related Disease Research Program

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Jennifer B Unger, PhD, University of Southern California

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
July 16, 2025

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
August 1, 2025

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
August 1, 2025

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
February 1, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
February 11, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
February 19, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
February 19, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
February 11, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
February 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • UP-CG-24-00013

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

survey is anonymous. Data will be publicly available on GitHub repository if a manuscript related to this study is accepted for publication

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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