PONE-D-20-26733

AGE OF INITIATION OF CIGARILLOS, FILTERED CIGARS AND/OR TRADITIONAL CIGARS AMONG YOUTH: FINDINGS FROM THE POPULATION ASSESSMENT OF TOBACCO AND HEALTH STUDY, 2013-2017

PLOS ONE

Dear Dr. Perez,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel the subject of your paper has merit but that the paper and analyses presented does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to consider a revised version of the manuscript that addresses the many excellent comments raised by our external reviewers. 

Please submit your revised manuscript by Oct 26 2020 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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We look forward to receiving your revised manuscript.

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Michael Cummings, PhD

Academic Editor

PLOS ONE

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Reviewers' comments:

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Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly

Reviewer #2: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: No

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Reviewer #1: Yes

Reviewer #2: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: AGE OF INITIATION OF CIGARILLOS, FILTERED CIGARS AND/OR TRADITIONAL CIGARS AMONG YOUTH: FINDINGS FROM THE POPULATION ASSESSMENT OF TOBACCO AND HEALTH STUDY, 2013-2017

This study used data from PATH to investigate the age of initiation of cigars among youth. The study found that cigar use starts early in the teenage years similar to cigarette use.

Page 7, line 118. Because of demographic differences in use of cigars as blunts (Cullen, J., Mowery, P., Delnevo, C., Allen, J. A., Sokol, N., Byron, M. J. and Thornton-Bullock, A. Seven-year patterns in US cigar use epidemiology among young adults aged 18-25 years: a focus on race/ethnicity and brand. Am J Public Health. 2011 Oct;101(10):1955-62. doi: 10.2105/AJPH.2011.300209. Epub 2011 Aug 18.), it is important to be clear how these subjects were treated. How specifically did the authors exclude blunt use? The PATH question is “Have you ever smoked part or all of a cigar, cigarillo or filtered cigar with marijuana in it?” Did the authors exclude all blunt users even if they had also been cigar users or did they approach this in another way? Please clarify this question for susceptibility, ever use, past 30-day use, and fairly regular use.

Page 7, line 120. The authors state that other studies combined cigarillo and filtered cigar use. But, why, for this specific study, was it necessary and advantageous to combine cigarillo and filtered cigar use? The demographics of use of these two classes of cigars are quite different. Cigarillos are widely used as blunts and filtered cigars are used as substitutes for cigarettes. It is also possible that age of initiation may be different. Were there data that suggested that these data from cigarillo and filtered cigars were equivalent and could be readily combined in the context of this study’s objectives?

Page 8, line 140 and following. The discussion of methods for ever use, past 30-day use, and fairly regular use are very repetitious. These can be combined by listing the three PATH questions and then explaining how the participants were categorized based on their responses without repeating these steps three times.

Page 9, line 173. How did the authors address dual use? Were dual users included or excluded? Were these exclusive cigar users or were cigar/cigarette dual users also included in the test population? If so, how many of each category were excluded due to dual users?

Page 12, line 230. Table 2 and Figures 1-3 are sowing the same data. Either the Tables or the Figures should be in Supplemental instead.

Page 20, line 333. But there may have been differences by race/ethnicity if the authors had analyzed cigarillo and filtered cigars separately.

Page 25, line 448. Since age of initiation of traditional cigar use is much higher than for cigarillo and filtered cigars (manuscript lines 389-390), what does that suggest for FDA regulation of these products? Should they be regulated differently? If FDA were to use a youth-protection rationale for regulating cigars, should they include traditional cigars in the regulation?

Page 26, line 460. Here the authors describe the reason they should be clear about their rationale and methods for excluding blunt users in this study.

Page 27, line 473. The authors need to discuss possible differences in the meaning of “fairly regular” between filtered cigar and traditional cigar use. Because traditional cigars are often used rarely (once per week or once per month), the understanding of “fairly regular” may be different from “fairly regular” use of filtered cigars or cigarillos.

Minor correction:

Page 6, line 111 – Correct to keep commas consistent.

Reviewer #2: Understanding patterns of cigar use initiation by age, race, gender, and product type is critical to develop appropriate prevention efforts and tobacco control policies. While this is an important study that contributes valuable knowledge to the field, there are several areas that can be improved. Namely, the importance of differentiating cigar product type can be better described in the Introduction and Discussion – the results indicated that different epidemiological patterns emerged when making this distinction, so this argument should be highlighted more prominently. Additionally, some methodological approaches can be more clearly described. Below are specific recommendations to improve the manuscript.

INTRODUCTION

- The authors acknowledged an important limitation of prior studies on cigar use, which often collapse different types of cigar products into one broad category. However, the importance of studying cigar use by type was not well-established in the Introduction. Why is it so critical to investigate these differences (e.g., are there differences in health risks, addiction potential, appeal, price, etc.)? This would make a more compelling case for the study.

- Similarly, it would be helpful to briefly describe how these 3 products differ in addition to size. For example, large cigars are generally used less frequently and are not commonly inhaled, some cigarillos are primarily used as blunts to smoke marijuana, filtered cigars are often used as cheaper cigarette substitutes. This is mentioned in the Discussion, but this context seems important to describe upfront.

METHODS

- The authors created a combined category for cigarillo and filtered cigar use, noting that this is “consistent with other published studies.” The collapsing of these categories is at odds with the authors’ criticism of prior studies detailed in the introduction. Moreover, the ways in which these products are regulated and used differ: little filtered cigars, which are sometimes indistinguishable from cigarettes, are usually sold in packs of 20 and are taxed at the same rate as cigarettes at the federal level. Cigarillos, however, vary more widely in their flavor offerings, pack sizes, cost, and consumer profiles. If the data are available, it seems like a missed opportunity to not distinguish between these products.

- The last sentence in the “Ever use” section repeats what was said in the second sentence and can be removed. This is true for the “Past 30 day use” and “Fairly regular use” sections, as well.

- The description about how age of initiation was determined (i.e., adding the number of weeks between waves to the participant’s age) was unclear. Without knowing their birthdate, how is this used to determine age? For example, two participants who are 16-years old at wave 1 could be almost a year apart in age. A combination of birthdate plus dates of survey waves would be more precise. Is this information available? More clarification is needed in this section.

- Another limitation is that it is not possible to determine the age when participants actually initiated each category of use (at least in my understanding of how these measures were described). For example, if in the second wave a participant states that they are an ever user, past 30 day user, or used fairly regularly, they may have “initiated” those behaviors immediately after wave 1, at the mid-point between waves, or just before wave 2. Since they are only asked about these behaviors during their interviews – but are not asked when these behaviors actually first occurred - how can the authors determine the age when these behaviors first took place?

RESULTS

- Because of the sample size issues for the “fairly regular” use variable (i.e., unstable estimates for traditional cigar use across all ages and across most ages for the other cigar variables), it might be worth considering dropping this variable from the analyses. This might also help pare down the paper, which has a fairly wide scope.

TABLES

- The title for Table 1 seems disjointed and is a bit confusing to interpret.

- In Table 1, it might be more interpretable to present the percentage of participants who use another tobacco product, instead of the average number of products used (which are all 1).

- In Table 5, some of the numbers for “fairly regular use” seem too high. For example, the cumulative incidence by 18 years old is over 50% for most groups, which is substantially higher than ever or past 30 day use.

- Moreover, in Table 5, why are only certain categories presented? (e.g., susceptibility only for traditional cigars, fairly regular use only for filtered cigars/cigarillos)

DISCUSSION

- There is a typo on page 25, line 444. It should read “2013-2014.”

- The authors should clarify their recommendation to differentiate cigar interventions by behavior (e.g., ever use, past 30 day, “fairly regular”). Traditionally, interventions target primary prevention or cessation. What is meant by this?

- The authors focus mainly on the filtered cigar/cigarillo findings, and briefly describe findings for traditional cigars, but the observed differences between these two products – especially by race – seem noteworthy and should be discussed in greater detail. White youth are more likely to initiate traditional cigars, whereas Black youth have considerably higher rates of initiation (and at earlier ages) for filtered cigars/cigarillos. The typical use behaviors (e.g., frequency, purpose) and product characteristics (e.g., price, flavorings, packaging size, accessibility, etc.) between these two categories differ, and may influence racial/ethnic disparities in youth tobacco use. Discussing this issue might be one way to justify the importance of analyzing cigar use epidemiology by product type, which the authors set out to do in the Introduction.

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6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

PONE-D-20-26733R1

AGE OF INITIATION OF CIGARILLOS, FILTERED CIGARS AND/OR TRADITIONAL CIGARS AMONG YOUTH: FINDINGS FROM THE POPULATION ASSESSMENT OF TOBACCO AND HEALTH STUDY, 2013-2017

PLOS ONE

Dear Dr. Perez,

Thank you for submitting your revised manuscript to PLOS ONE. After careful consideration, we feel that it has merit, however reviewer #2  had a few additional, relatively minor issues for you to address before we can accept this for publication.  Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Dec 25 2020 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

We look forward to receiving your revised manuscript.

Kind regards,

Michael Cummings, PhD

Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: (No Response)

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: No

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: I have no further comments to make to the authors. You have doe a great job in addressing my previous comments.

Reviewer #2: The authors did a commendable job revising this manuscript, which is considerably clearer and stronger. While the Introduction and Discussion sections are substantially improved, I still think a sentence or two could be added about why it is so important to differentiate cigars by subtype from a health perspective. The authors did a great job describing how the products look different and are used differently, but why is this important for individual/population health? One thought is that smaller cigars are generally used more frequently and are often inhaled, while traditional cigars are usually not inhaled and are used more infrequently. This could potentially influence their addictive potential or even their health risks. Two minor comments are listed below:

Pg. 4, lines 67-71: The second part of this sentence (i.e., “socializing when smoking traditional cigars was reported in 2013-2014 with the highest proportion for traditional cigar use exhibited among adults”) was unclear. The sentence would benefit from restructuring.

Pg. 7, lines 140-141: The sentence “PATH excluded ‘blunt-only’ users” makes it sound like these individuals were excluded from the PATH study. Please clarify that PATH created derived variables for cigar product use, and that blunt-only users were excluded from these variables.

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

AGE OF INITIATION OF CIGARILLOS, FILTERED CIGARS AND/OR TRADITIONAL CIGARS AMONG YOUTH: FINDINGS FROM THE POPULATION ASSESSMENT OF TOBACCO AND HEALTH STUDY, 2013-2017

PONE-D-20-26733R2

Dear Dr. Perez,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Michael Cummings, PhD

Academic Editor

PLOS ONE

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