Waterpipe SizeNCT05705375
Effect of Waterpipe Size on Smoking Behavior and Exposures
A study testing Waterpipe size in people with Waterpipe Size, run by The University of Texas at Arlington at 1 site in United States.
Trial summary
The goal of this clinical trial is to learn how waterpipe (WP) size affects smoking behavior, toxicant exposure, and subjective experiences in young adult WP smokers (ages 21-39). Read more about this study
- Who is it for?
- Ages 21 to 39 yearsHealthy volunteers can take part
- Conditions the study is for
- Waterpipe Size
- What is being tested?
- Waterpipe size
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 40 participants
- Where
- 1 siteUnited States
- Study dates
- 22 Apr 2022to 30 Mar 2024
- Phase
- Interventional
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 21 to 39 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- regular waterpipe smokers (smoking at least once a week for the past 6 months)
- generally healthy and
- able to provide written informed consent; and willing to attend the 3 lab sessions
Who cannot join
- history of chronic diseases such as diabetes, high blood cholesterol, hepatic disease
- respiratory chronic diseases
- cardiovascular diseases including low or high blood pressure (BP)
Trial locations and contacts
1 site in 1 country.
United States1 site
University of Texas at Arlington
Arlington, Texas, 76019
About this study
Official title: Understanding the Effect of Waterpipe Size on Smoking Behavior, Toxicant Exposures and Subjective Experiences
The goal of this clinical trial is to learn how waterpipe (WP) size affects smoking behavior, toxicant exposure, and subjective experiences in young adult WP smokers (ages 21-39). The main questions it aims to answer are:
- Does WP size change puffing behavior?
- Does WP size change exposure to nicotine and carbon monoxide?
- Does WP size change perceptions of harm, satisfaction, craving, or withdrawal?
Participants will smoke small, medium, and large WPs in separate sessions. Researchers will measure puffing behavior, saliva nicotine, exhaled carbon monoxide, and survey responses before and after each session.
Read the detailed description
This study will examine the effect of waterpipe (WP) size manipulation on smoking behavior, toxicant exposure, and subjective experiences among young adult WP smokers. A total of 40 participants ages 21-39 will complete a 2x3 crossover design, where the within-subject factors are time (pre vs. post WP smoking) and study condition (small vs. medium vs. large). Each participant will attend three 45-minute laboratory sessions, each using a different WP size.
Aim 1: To examine the effect of WP size on puffing behavior and toxicant exposure. Puff topography parameters (puff number, duration, average puff volume, total inhaled volume, and inter-puff interval) will be measured during smoking. Exhaled CO and saliva nicotine concentrations will be measured pre- and post-session.
Aim 2: To examine the effect of WP size on harm perception and subjective experiences. Outcomes include harm perception, WP Evaluation Scale, Duke Sensory Questionnaire, Questionnaire of Smoking Urges (brief), and Minnesota Nicotine Withdrawal Scale.
This project will generate novel evidence on how WP size influences smoking behavior, exposure to nicotine and CO, and user perceptions. Findings will inform the FDA on the potential impact of WP size regulation and help guide the development of size-specific standards to protect public health.
- Conditions
- Waterpipe Size
- Being tested
- Waterpipe size
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Waterpipe sizeOther
Participants will have 3 lab visits where they are allocated (random order) to smoke a small waterpipe in one visit, smoke a medium waterpipe in a second visit and smoke a large waterpipe in a third visit.
| Study group | Role | What they receive |
|---|---|---|
| waterpipe regular smokers | Experimental | waterpipe regular smokers will be invited for 3 lab visits where they are allocated (random order) to smoke 3 waterpipe different sizes. Receives: Other: Waterpipe size |
What is being measured
The primary outcome is the main question the study is designed to answer.
Waterpipe Evaluation Scale
An 11-item questionnaire assessing participants' subjective experience of smoking waterpipe (WP) tobacco. Each item is scored on a 7-point Likert scale (1 = "not at all" to 7 = "extremely"). For analysis, item scores were averaged across the 11 items to produce a mean WES score for each WP size, with higher scores indicating a more satisfactory smoking experience. The scale captures aspects such as satisfaction, taste, cravings, and sensory enjoyment in the throat and chest.
Measured: Immediately after the exposure (smoking)
Duke Sensory Questionnaire
A 9-item questionnaire assessing participants' sensory experience of smoking waterpipe (WP) tobacco. Each item is scored on a 7-point Likert scale (1 = "not at all" to 7 = "extremely"). Item scores were averaged across the 9 items to produce a mean DSQ score for each WP size, with higher scores indicating a more positive sensory experience (e.g., satisfaction, perceived nicotine strength, and puff intensity).
Measured: Immediately after the exposure (smoking)
Harm Perception Questionnaire
This is a 3-item scale assessing participants' perception of the harmfulness of waterpipe (WP) tobacco smoking. Each item is scored on a 7-point Likert scale ranging from 1 = "a lot less harmful" to 7 = "a lot more harmful." Item scores were averaged across the 3 items to produce a mean harm perception score for each WP size, with higher scores indicating greater perceived harm.
Measured: Immediately after the exposure (smoking)
Saliva Nicotine
How participants' nicotine concentrations change based on the different smoked waterpipe sizes
Measured: Immediately after the exposure (smoking)
Puff Topography: Smoking Time
The total time spent smoking during a single WP session, measured in minutes. Longer times indicate greater duration of smoking across WP sizes.
Measured: During the exposure (smoking), up to 45 mins
Puff Topography: Cumulative Puff Time
The total time spent actively inhaling smoke across all puffs in a WP session, measured in minutes using a puff topography device. Higher values indicate more total inhalation time.
Measured: During the exposure (smoking), up to 45 mins
Puff Topography: Puff Duration
The average length of each puff in seconds, measured using a puff topography device in the WP hose. Longer puff duration indicates deeper inhalation per puff.
Measured: During the exposure (smoking), up to 45 mins
Puff Topography: Average Flow Rate
The average rate of smoke inhaled per second during puffing, measured in liters per minute with a puff topography device. Higher flow rates indicate faster inhalation.
Measured: During the exposure (smoking), up to 45 mins
Puff Topography: Number of Puffs
The total number of puffs taken during a WP session, measured using a puff topography device. Higher counts indicate more frequent puffing.
Measured: During the exposure (smoking), up to 45 mins
Puff Topography: Total Smoke Volume Inhaled
Total smoke inhaled during a single WP session, measured in liters using a puff topography device in the WP hose. Higher values indicate greater smoke intake across WP sizes.
Measured: During the exposure (smoking), up to 45 mins
Puff Topography: Puff Volume Average
Mean volume of each puff during a WP session, measured in liters using a puff topography device in the WP hose. Higher values indicate larger puff sizes across WP sizes.
Measured: During the exposure (smoking), up to 45 mins
Puff Topography: Maximum Puff Volume
The largest single puff volume inhaled during a WP session, measured in liters using a puff topography device. Higher values indicate the strongest inhalation effort across puffs.
Measured: During the exposure (smoking), up to 45 mins
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Jan 2023
- Study start22 Apr 2022
- Primary completion28 Feb 2024
- Study completion30 Mar 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for Waterpipe SizeStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 40 participants (actual)
Sponsor and investigators
- Lead sponsor
- The University of Texas at Arlington
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05705375
- Sponsor's protocol ID
- 2021-0458
- Status last verified
- Sep 2025
- First submitted
- 22 Dec 2022
- Last updated
- 5 Nov 2025
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 5 Nov 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Understanding the Effect of Waterpipe Size on Smoking Behavior, Toxicant Exposures and Subjective Experiences
- ClinicalTrials.gov ID
- NCT05705375
- Acronym / sponsor ID
- 2021-0458
- Conditions
- Waterpipe Size
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 40 participants (actual)
- Lead sponsor
- The University of Texas at ArlingtonUniversity, hospital or other
- Study start
- 22 Apr 2022 (actual)
- Primary completion
- 28 Feb 2024 (actual)
- Study completion
- 30 Mar 2024 (actual)
- First posted
- 30 Jan 2023 (actual)
- Results
- Posted 5 Nov 2025
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this clinical trial is to learn how waterpipe (WP) size affects smoking behavior, toxicant exposure, and subjective experiences in young adult WP smokers (ages 21-39). The main questions it aims to answer are:
- Does WP size change puffing behavior?
- Does WP size change exposure to nicotine and carbon monoxide?
- Does WP size change perceptions of harm, satisfaction, craving, or withdrawal?
Participants will smoke small, medium, and large WPs in separate sessions. Researchers will measure puffing behavior, saliva nicotine, exhaled carbon monoxide, and survey responses before and after each session.
Detailed description
This study will examine the effect of waterpipe (WP) size manipulation on smoking behavior, toxicant exposure, and subjective experiences among young adult WP smokers. A total of 40 participants ages 21-39 will complete a 2x3 crossover design, where the within-subject factors are time (pre vs. post WP smoking) and study condition (small vs. medium vs. large). Each participant will attend three 45-minute laboratory sessions, each using a different WP size.
Aim 1: To examine the effect of WP size on puffing behavior and toxicant exposure. Puff topography parameters (puff number, duration, average puff volume, total inhaled volume, and inter-puff interval) will be measured during smoking. Exhaled CO and saliva nicotine concentrations will be measured pre- and post-session.
Aim 2: To examine the effect of WP size on harm perception and subjective experiences. Outcomes include harm perception, WP Evaluation Scale, Duke Sensory Questionnaire, Questionnaire of Smoking Urges (brief), and Minnesota Nicotine Withdrawal Scale.
This project will generate novel evidence on how WP size influences smoking behavior, exposure to nicotine and CO, and user perceptions. Findings will inform the FDA on the potential impact of WP size regulation and help guide the development of size-specific standards to protect public health.
Study design
- Primary purpose
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| waterpipe regular smokers | Experimental | Other: Waterpipe sizewaterpipe regular smokers will be invited for 3 lab visits where they are allocated (random order) to smoke 3 waterpipe different sizes. |
Who may qualify
- Ages
- 21 to 39 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- regular waterpipe smokers (smoking at least once a week for the past 6 months)
- generally healthy and
- able to provide written informed consent; and willing to attend the 3 lab sessions
Key exclusion criteria (3 listed)
- history of chronic diseases such as diabetes, high blood cholesterol, hepatic disease
- respiratory chronic diseases
- cardiovascular diseases including low or high blood pressure (BP)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Waterpipe sizeParticipants will have 3 lab visits where they are allocated (random order) to smoke a small waterpipe in one visit, smoke a medium waterpipe in a second visit and smoke a large waterpipe in a third visit. | Other | waterpipe regular smokers |
Primary outcome
Waterpipe Evaluation Scale
Time frame: Immediately after the exposure (smoking)
An 11-item questionnaire assessing participants' subjective experience of smoking waterpipe (WP) tobacco. Each item is scored on a 7-point Likert scale (1 = "not at all" to 7 = "extremely"). For analysis, item scores were averaged across the 11 items to produce a mean WES score for each WP size, with higher scores indicating a more satisfactory smoking experience. The scale captures aspects such as satisfaction, taste, cravings, and sensory enjoyment in the throat and chest.
Duke Sensory Questionnaire
Time frame: Immediately after the exposure (smoking)
A 9-item questionnaire assessing participants' sensory experience of smoking waterpipe (WP) tobacco. Each item is scored on a 7-point Likert scale (1 = "not at all" to 7 = "extremely"). Item scores were averaged across the 9 items to produce a mean DSQ score for each WP size, with higher scores indicating a more positive sensory experience (e.g., satisfaction, perceived nicotine strength, and puff intensity).
Harm Perception Questionnaire
Time frame: Immediately after the exposure (smoking)
This is a 3-item scale assessing participants' perception of the harmfulness of waterpipe (WP) tobacco smoking. Each item is scored on a 7-point Likert scale ranging from 1 = "a lot less harmful" to 7 = "a lot more harmful." Item scores were averaged across the 3 items to produce a mean harm perception score for each WP size, with higher scores indicating greater perceived harm.
Saliva Nicotine
Time frame: Immediately after the exposure (smoking)
How participants' nicotine concentrations change based on the different smoked waterpipe sizes
Puff Topography: Smoking Time
Time frame: During the exposure (smoking), up to 45 mins
The total time spent smoking during a single WP session, measured in minutes. Longer times indicate greater duration of smoking across WP sizes.
Puff Topography: Cumulative Puff Time
Time frame: During the exposure (smoking), up to 45 mins
The total time spent actively inhaling smoke across all puffs in a WP session, measured in minutes using a puff topography device. Higher values indicate more total inhalation time.
Puff Topography: Puff Duration
Time frame: During the exposure (smoking), up to 45 mins
The average length of each puff in seconds, measured using a puff topography device in the WP hose. Longer puff duration indicates deeper inhalation per puff.
Puff Topography: Average Flow Rate
Time frame: During the exposure (smoking), up to 45 mins
The average rate of smoke inhaled per second during puffing, measured in liters per minute with a puff topography device. Higher flow rates indicate faster inhalation.
Puff Topography: Number of Puffs
Time frame: During the exposure (smoking), up to 45 mins
The total number of puffs taken during a WP session, measured using a puff topography device. Higher counts indicate more frequent puffing.
Puff Topography: Total Smoke Volume Inhaled
Time frame: During the exposure (smoking), up to 45 mins
Total smoke inhaled during a single WP session, measured in liters using a puff topography device in the WP hose. Higher values indicate greater smoke intake across WP sizes.
Puff Topography: Puff Volume Average
Time frame: During the exposure (smoking), up to 45 mins
Mean volume of each puff during a WP session, measured in liters using a puff topography device in the WP hose. Higher values indicate larger puff sizes across WP sizes.
Puff Topography: Maximum Puff Volume
Time frame: During the exposure (smoking), up to 45 mins
The largest single puff volume inhaled during a WP session, measured in liters using a puff topography device. Higher values indicate the strongest inhalation effort across puffs.
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 Nov 2025.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Individual participant dataSharing planned: No
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Waterpipe size in people with Waterpipe Size, run by The University of Texas at Arlington at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 5 Nov 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Yes. Results are posted in the registry (first posted 5 Nov 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Waterpipe Evaluation Scale (time frame: Immediately after the exposure (smoking)). The study lists 12 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Nov 2025.