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Identifying Reliable Labeling Comprehension Questions for E-Vapor and Heated Tobacco Products: A Meta-Analytic Approach Cover

Identifying Reliable Labeling Comprehension Questions for E-Vapor and Heated Tobacco Products: A Meta-Analytic Approach

Open Access
|Sep 2026

Figures & Tables

Table 1.

Labeling comprehension questions and respective user guide information by question domain.

StudyQuestionAnswer in user guide
Know to charge device only with proprietary accessories
HTP #1 Formative studyJonah lost the AC adapter and USB cable charger for his device, but he has another charger that he uses for his phone. According to the materials, what should Jonah do or not do?Charge only with the dedicated and recommended USB cable and AC adapter.
Charge only with the provided adapter and USB Cable
HTP #2 Formative studyJonah lost the charger for his device, but he has another USB cable that he uses for his phone.Be sure to use the supplied USB type-C cable.
According to the materials, what should Jonah do or not do?CHARGE WITH INCLUDED CABLE
HTP #1 Summative studyJonah lost the AC adapter and USB cable charger for his device, but he has another charger that he uses for his phone. According to the materials, what should Jonah do or not do?Charge only with the dedicated and recommended USB cable and AC adapter.
Charge only with the provided adapter and USB Cable
ENDS #1 Summative studyDave's ENDS #1 battery needs charging, but he cannot find his ENDS #1 USB charger. According to the Guide, should Dave try to charge his ENDS #1 e-vapor device with any other charging device?Do not attempt to charge the ENDS #1 battery with any other charging device.
Know to not use device if it is operating in a strange manner
HTP #1 Formative studyJulio noticed that his device does not appear to be vibrating or pulsating correctly. According to the materials, what should Julio do or not do?Do not use or charge your device or its accessories if any of them:
  • - Appears BROKEN or DAMAGED

  • - Operates in an erratic manner

HTP #2 Formative studyJulio noticed that the display was glitchy and there were flashing and changing icons. According to the materials, what should Julio do or not do?To reduce the risk of injury, do not use your device or items if they:
  • - Appear damaged or broken

  • - Are operating in an erratic manner.

HTP #1 Summative studyJulio noticed that his device does not appear to be vibrating or pulsating correctly. According to the materials, what should Julio do or not do?Do not use or charge your device or its accessories if any of them:
  • - Appears BROKEN or DAMAGED

  • - Operates in an erratic manner

ENDS #1 Summative studyRose noticed that her ENDS #1 e-vapor device was operating erratically. According to the Guide, what should Rose do when she noticed that her ENDS #1 e-vapor device was operating erratically?To reduce the risk of injury, do not use your ENDS #1 e-vapor device or items if they:
  • - Appear broken or damaged

  • - Are operating in an erratic manner

Know to not expose device to high temperatures
HTP #1 Formative studyOmar left his device sitting in his car, with outside temperatures reaching over 100 degrees. According to the materials, what should Omar do or not do?Do not use or charge your device or its accessories if any of them:
  • - Has been exposed to EXCESSIVE HEAT

DO NOT leave or charge the device near heat sources, such as:
  • - Radiators or stoves

  • - Direct sunlight

  • - Inside a vehicle on a hot day

HTP #2 Formative studyOmar left his device sitting on top of a hot radiator while charging it.Do not use, store or charge any items in or near heat sources such as radiators, stoves, hot appliances, or fires. High or low temperatures may cause battery fluid leakage, thermal burns, battery explosion or fire.
What could potentially happen?
HTP #1 Summative studyOmar has left his device sitting in his car, with outside temperatures reaching over 100 degrees. According to the materials, what should Omar do or not do?Do not use or charge your device or its accessories if any of them:
  • - Has been exposed to EXCESSIVE HEAT

DO NOT leave or charge the device near heat sources, such as:
  • - Radiators or stoves

  • - Direct sunlight

  • - Inside a vehicle on a hot day.

ENDS #1 Summative studyTim realized that he had left his ENDS #1 e-vapor device on top of a hot radiator, and it felt unusually hot to the touch when he picked it up. According to the Guide, what should Tim do if device felt unusually hot to the touch?To reduce the risk of injury, do not use your ENDS #1 e-vapor device or items if they:
  • - Have been exposed to excessive heat

  • - Are unusually hot to the touch.

Know to not use device if it becomes wet or immersed in a liquid.
HTP #1 Formative studyAmaya dropped her device in a sink full of water. According to the materials, what should Amaya do or not do?Do not use or charge your device or its accessories if any of them:
  • - Becomes wet or has been immersed in any liquid.

HTP #2 Formative studyAmaya dropped her device in a sink full of water. According to the materials, what should Amaya do or not do?To reduce the risk of injury do not use your device or items if they:
  • - Become wet or immersed in any liquid.

HTP #1 Summative studyAmaya dropped her device in a sink full of water. According to the materials, what should Amaya do or not do?Do not use or charge your device or its accessories if any of them:
  • - Becomes wet or has been immersed in any liquid.

ENDS #1 Summative studyLiz's ENDS #1 e-vapor device was immersed in water when she dropped it in the sink while washing dishes. According to the Guide, what should Liz do if ENDS #1 e-vapor device was immersed in water?To reduce the risk of injury, do not use your ENDS #1 e-vapor device or items if they:
  • - Become wet or are immersed in any liquid

Know to not use device if it appears damaged or broken
HTP #1 Formative studyLee noticed that the sliding door at the top of his device is broken. According to the materials, what should Lee do or not do?Do not use or charge your device or its accessories if any of them:
  • - Appears BROKEN or DAMAGED

  • - Operates in an erratic manner

HTP #2 Formative studyLee dropped his device, and it's no longer working properly. According to the materials, what should Lee do or not do?To reduce the risk of injury, do not use your device or items if they:
  • - Appear damaged or broken

HTP #1 Summative studyLee noticed that the sliding door at the top of his device is broken. According to the materials, what should Lee do or not do?Do not use or charge your device or its accessories if any of them:
  • - Appears BROKEN or DAMAGED

  • - Operates in an erratic manner

ENDS #1 Summative studyJohn dropped his ENDS #1 e-vapor device and it broke. According to the Guide, what should John do to reduce the risk of injury after it broke?To reduce the risk of injury, do not use your ENDS #1 e-vapor device or items if they:
  • - Appear damaged or broken.

Know to keep device away from children
HTP #1 Formative studyAccording to the materials, who should this product be kept away from?KEEP THE DEVICE, ITS ACCESSORIES AND THE TOBACCO STICKS OUT OF REACH OF CHILDREN AND PETS
KEEP OUT OF REACH (device, accessories, and tobacco sticks) OF CHILDREN AND PETS
HTP #2 Formative studyAccording to the materials, who should this product be kept away from?To reduce the risk of choking or poisoning:
  • - Keep the device and items out of the reach of children.

HTP #1 Summative studyAccording to the materials, who should this product be kept away from?KEEP THE DEVICE, ITS ACCESSORIES AND THE TOBACCO STICKS OUT OF REACH OF CHILDREN AND PETS
KEEP OUT OF REACH (device, accessories, and tobacco sticks) OF CHILDREN AND PETS
ENDS #1 Summative studyAccording to the Guide, should Sam leave his spare cartridges on his short table when his young children are in the room?To reduce the risk of choking or poisoning:
  • - Keep the ENDS #1 e-vapor device and items out of the reach of children.

Do not leave ENDS #1 items unattended where children or pets could gain access to them.
Know that the device contains nicotine
HTP #1 Formative studyAccording to the materials, what addictive chemical does this product contain?The compatible tobacco sticks contain tobacco and nicotine.
Nicotine is an addictive substance.
HTP #2 Formative studyAccording to the materials, what addictive chemical does this product contain?To reduce the risk of choking or poisoning:
  • - Each capsule contains nicotine.

HTP #1 Summative studyAccording to the materials, what addictive chemical does this product contain?The compatible tobacco sticks contain tobacco and nicotine.
Nicotine is an addictive substance.
Know not to use the device with other manufacturer's items
HTP #1 Formative studyAnnette ran out of tobacco sticks, but she has sticks for a different brand's device. According to the materials, what should Annette do or not do?Use only genuine tobacco sticks and accessories intended for use with this device.
HTP #2 Formative studyAnnette ran out of HTP #2 capsules, but she has a capsule for a different brand's device. According to the materials, what should Annette do or not do?Do not use any items with any other manufacturer's heated tobacco device items.
HTP #1 Summative studyAnnette ran out of tobacco sticks, but she has sticks for a different brand's device. According to the materials, what should Annette do or not do?Use only genuine tobacco sticks and accessories intended for use with this device.
Know that the product contains tobacco
HTP #1 Formative studyAccording to the materials, what is inside the stick?The compatible tobacco sticks contain tobacco and nicotine.
HTP #2 Formative studyAccording to the materials, what is the capsule filled with?Insert a real tobacco filled capsule into the palm-sized device to get started.
HTP #1 Summative studyAccording to the materials, what is inside the stick?The compatible tobacco sticks contain tobacco and nicotine.
Know that the device heats the tobacco
HTP #1 Formative studyAccording to the materials, what does the device do to the tobacco?The device heats the tobacco to a high temperature.
HTP #2 Formative studyAccording to the materials, what does the device do to the tobacco?Your HTP #2 system provides a new experience by heating real tobacco without burning it.
HTP #1 Summative studyAccording to the materials, what does the device do to the tobacco?The device heats the tobacco to a high temperature.
Know how many times you can use the tobacco consumable
HTP #1 Formative studyAccording to the materials, how many times can you use a stick?ONLY USE THE TOBACCO STICK ONCE
HTP #2 Formative studyAccording to the materials, how many times can you use a capsule?Each HTP #2 capsule is single use and should not be re-heated, even if a session is stopped early. HTP #2 capsules may not be heated more than once.
HTP #1 Summative studyAccording to the materials, how many times can you use a tobacco stick?ONLY USE THE TOBACCO STICK ONCE
Know how long the tobacco consumable will last
HTP #1 Formative studyAccording to the materials, after preheating, approximately how long will the experience last?A session will last about 5 minutes.
HTP #2 Formative studyAccording to the materials, after preheating, approximately how long will the experience last?Capsules last about 7 minutes or 20 puffs.
HTP #1 Summative studyAccording to the materials, after preheating, approximately how long will the experience last?A session will last about 5 minutes.
Know not to use the device if the battery behaves unexpectedly
HTP #1 Formative studyThe battery in Annie's device appears to be leaking, what should Annie do?DO NOT use or charge the device if the battery appears to be leaking.
  • - DO NOT touch with bare hands.

  • - DO NOT touch eyes.

  • - If the liquid is swallowed, immediately call a doctor.

  • - In case of contact with skin, wash hands with plenty of soap and water.

HTP #1 Summative studyThe battery in Annie's device appears to be leaking. According to the materials, what should Annie do or not do?DO NOT use or charge the device if the battery appears to be leaking.
  • - DO NOT touch with bare hands.

  • - DO NOT touch eyes.

  • - If the liquid is swallowed, immediately call a doctor.

  • - In case of contact with skin, wash hands with plenty of soap and water.

ENDS #1 Summative studyAl's ENDS #1 battery no longer holds a charge. According to the Guide, should he try to service or repair it himself?To reduce the risk of injury:
  • - Your e-vapor device and items contain no user-serviceable parts. Do not attempt to open, service, or repair; doing so may cause electric shock, thermal burns or fire.

[i] Note: Information descriptions in the “Answer in User Guide” column are formatted as they appeared in the product materials from this research.

Table 2.

Results of the proportional meta-analyses by question domain.

Question domainPooled proportion and 95% CIPrediction interval PIQP-value for QI2Tau2
Know to charge device only with proprietary accessories0.99 [0.95, 1.00][0.85, 1.00]5.340.1543.8%0.004
Know to not use device if it is operating in a strange manner0.86 [0.68, 0.98][0.19, 1.00]23.68<.0001*87.3%0.036
Know to not expose device to high temperatures0.96 [0.93, 0.98][0.90, 0.99]2.120.550.0%0.000
Know to not use device if it becomes wet or immersed in a liquid0.98 [0.94, 1.00][0.88, 1.00]3.890.2723.0%0.002
Know to not use device if it appears damaged or broken0.97 [0.93, 1.00][0.87, 1.00]3.920.2723.0%0.002
Know to keep device away from children0.86 [0.46, 1.00][0.00, 1.00]23.070.0001*91.3%0.123
Know that the device contains nicotine0.95 [0.73, 1.00][0.00, 1.00]10.970.004*81.8%0.051
Know not to use the device with other manufacturer's items0.99 [0.95, 1.00][0.88, 1.00]1.940.380.0%0.000
Know that the product contains tobacco0.91 [0.77, 1.00][0.28, 1.00]4.600.1056.5%0.015
Know that the device heats the tobacco1.00 [0.97, 1.00][0.90, 1.00]0.030.990.00%0.000
Know how many times you can use the tobacco consumable0.93 [0.56, 1.00][0.00, 1.00]23.850.0001*91.6%0.124
Know how long the tobacco consumable will last0.89 [0.64, 1.00][0.00, 1.00]10.990.004*81.8%0.051
Know not to use the device if the battery behaves unexpectedly0.97 [0.86, 1.00][0.33, 1.00]12.290.002*83.7%0.021

[i] Note: Asterisks (*) indicate a statistically significant Q value (i.e., statistically significant heterogeneity). I2 and Tau2 describe the observed heterogeneity. P-values are formatted into two decimal places, except for lower values that necessitate additional figures for reporting accuracy.

DOI: https://doi.org/10.2478/cttr-2026-0011 | Journal eISSN: 2719-9509 (formerly 1612-9237)
Language: English, French, German
Page range: 157 - 166
Submitted on: Jan 22, 2026
Accepted on: May 28, 2026
Published on: Sep 18, 2026
Published by: Beiträge zur Tabakforschung GmbH
In partnership with: Paradigm Publishing Services

© 2026 Jonathan M. Gallegos, Jennifer N. Lewis, Elizabeth Becker, published by Beiträge zur Tabakforschung GmbH
This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License.