Testing Warning Labels for Retail Cannabis Products Using a Discrete Choice Experiment

July 24, 2026 updated by: University of Oklahoma

Developing and Testing Warning Labels for Retail Cannabis Products

This discrete choice experiment (DCE) study aims to address gaps in cannabis packaging regulatory research by testing how variations in cannabis packaging and health warning design impact reactions to packaging and intentions about cannabis use. The goal of this work is to identify the most effective combination of health warning features to improve consumer awareness of cannabis health risks. Establishing criteria for cannabis products in the US is critical because inconsistent state guidelines have resulted in contradictory policies in legal retail states, arguably leading to increased hazardous use and failure to meet public health standards. The contributions of this study's outcomes are expected to be significant because they will benefit public health as cannabis becomes available in legal retail markets and regulatory and governmental agencies seek effective ways to communicate cannabis risks to the public.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

The DCE will be conducted via a self-administered online questionnaire, with inclusion criteria assessed before assignment to choice set conditions. Participants will be residents of legal-retail cannabis use states, able to legally purchase cannabis (21 or older), who have used cannabis in the past 30 days (i.e., current use). Frequency of cannabis use (i.e., monthly, weekly, daily), mode (e.g., flower, vape, etc.), and dose (i.e., THC level) will be measured through self-report. Inclusion criteria are reported using cannabis (any mode) in the past 30 days. Consented participants will be presented with descriptions of cannabis packaging attributes and an example choice set to become familiar with DCE tasks. Participants will be asked to imagine the cannabis products in the DCE as the only choices they have available to them "in the near future" and to evaluate images within this scenario. Participants will be randomly assigned to view 16 choice sets. To optimize the evaluation of preferences and reduce respondent burden, we will assign contrasting labels to "choice sets," each of which will include 4 images of products in such a way that each attribute level appears an equal number of times in combination with all other attribute levels. Presentation order of the 16 choice sets will be randomized within and across choice sets to minimize ordering effects. Participants will view each choice set for as long as they wish. After evaluating choice sets, participants will complete a recall task to assess retention of health warning information and will be provided a debrief page with information about substance use and resources for seeking help with substance use.

Study Type

Interventional

Enrollment (Estimated)

450

Phase

  • 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 Contact

Study Locations

  • United States
    • Oklahoma
      • Oklahoma City, Oklahoma, United States, 73104
        • Recruiting
        • University of Oklahoma
        • Contact:

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

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Study Population

The study population consists of adults aged 21 years and older residing in U.S. states with legal retail cannabis markets (i.e., adult use non-medical or "recreational") who report cannabis use within the past 30 days. Participants will be recruited from an online consumer research panel and will represent active adult cannabis consumers in these jurisdictions.

Description

Eligibility for participation includes: 1) being 21 years of age or older, 2) being able to speak and understand English, 3) self-reported having consumed cannabis in the last 30 days (any mode, e.g., flower, vape, edible, etc.), and 4) residing in a U.S. state or jurisdiction where retail (i.e., non-medical) cannabis use is legal.

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: Prevention
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Discrete choice experiment (DCE) cohort
Adult participants (21+) enrolled in this single-arm cohort will complete a computer-based discrete choice experiment during a single study visit (conducted online). They will review a series of hypothetical cannabis products and select their preferred options.
Behavioral: Discrete choice experiment (DCE) survey-experiment
A discrete choice experiment (DCE) consisting of 16 distinct choice sets. Each choice set presents combinations of the following attributes: 1) Cannabis package style: 1) "Standardized" plain package, 2) plain package with brand logo and fonts, 3) brand color background with brand logo and fonts, and 4) fully branded with brand imagery, brand logo, and brand descriptors and fonts. Branding type: 1) Adventure brand vs. 2) Earthy brand. Health warning size: 1) Small (20% of packaging surface) - health warnings use currently mandated warning language from multiple jurisdictions vs. 2) Large (40% of packaging surface) - health warnings use currently mandated warning language from multiple jurisdictions. Product THC content: 1) Low THC vs. 2) High THC. Product type: 1) Joints, 2) Vape, 3) Edibles, and 4) Drinks. Participants will rate all combinations of product attributes.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Risk perceptions about cannabis products
Time Frame: At the time of survey completion (approximately 15 minutes)
Binary measure using best-worst scaling. For each question, participants will also have the option of indicating none of the above/opt-out as a response. For each choice set, the statement selected as the best option will be coded using a value of 1, and the worst will be coded as -1. The remaining statements in that set will be coded as 0. If the participant selects none of the above, all statements in that choice set will be assigned a value of 0.
At the time of survey completion (approximately 15 minutes)
Cannabis product use intentions
Time Frame: At the time of survey completion (approximately 15 minutes)
Binary measure using best-worst scaling. For each question, participants will also have the option of indicating none of the above/opt-out as a response. For each choice set, the statement selected as the best option will be coded using a value of 1, and the worst will be coded as -1. The remaining statements in that set will be coded as 0. If the participant selects none of the above, all statements in that choice set will be assigned a value of 0.
At the time of survey completion (approximately 15 minutes)

Collaborators and Investigators

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

Sponsor

University of Oklahoma

Collaborators

National Institute on Drug Abuse (NIDA)

Investigators

  • Principal Investigator: Zachary Massey, PhD, University of Oklahoma

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)

May 19, 2026

Primary Completion (Estimated)

December 31, 2026

Study Completion (Estimated)

December 31, 2026

Study Registration Dates

First Submitted

July 7, 2026

First Submitted That Met QC Criteria

July 7, 2026

First Posted (Actual)

July 14, 2026

Study Record Updates

Last Update Posted (Actual)

July 27, 2026

Last Update Submitted That Met QC Criteria

July 24, 2026

Last Verified

July 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 17276
  • 1K01DA057395-01A1 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

IPD Plan Description

The data that support the findings of this study are available from the corresponding author upon reasonable request.

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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