Peer Review History

Original SubmissionJanuary 10, 2024
Decision Letter - Davor Plavec, Editor

PONE-D-23-39727Comparative analysis of pulmonary ventilation distribution between low-cost and branded incentive spirometers using electrical impedance tomography in healthy adults: Study protocol.PLOS ONE

Dear Dr. Benavides-Cordoba,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

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We look forward to receiving your revised manuscript.

Kind regards,

Davor Plavec, MD, MSc, PhD, Prof.

Academic Editor

PLOS ONE

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Additional Editor Comments:

Dear Authors,

please make a revision of your manuscript as suggested by the reviewers or write a detailed rebuttal on a point-by-point basis.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Does the manuscript provide a valid rationale for the proposed study, with clearly identified and justified research questions?

The research question outlined is expected to address a valid academic problem or topic and contribute to the base of knowledge in the field.

Reviewer #1: Yes

Reviewer #2: Partly

Reviewer #3: No

**********

2. Is the protocol technically sound and planned in a manner that will lead to a meaningful outcome and allow testing the stated hypotheses?

The manuscript should describe the methods in sufficient detail to prevent undisclosed flexibility in the experimental procedure or analysis pipeline, including sufficient outcome-neutral conditions (e.g. necessary controls, absence of floor or ceiling effects) to test the proposed hypotheses and a statistical power analysis where applicable. As there may be aspects of the methodology and analysis which can only be refined once the work is undertaken, authors should outline potential assumptions and explicitly describe what aspects of the proposed analyses, if any, are exploratory.

Reviewer #1: Yes

Reviewer #2: No

Reviewer #3: No

**********

3. Is the methodology feasible and described in sufficient detail to allow the work to be replicable?

Descriptions of methods and materials in the protocol should be reported in sufficient detail for another researcher to reproduce all experiments and analyses. The protocol should describe the appropriate controls, sample size calculations, and replication needed to ensure that the data are robust and reproducible.

Reviewer #1: Yes

Reviewer #2: No

Reviewer #3: No

**********

4. Have the authors described where all data underlying the findings will be made available when the study is complete?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception, at the time of publication. 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: Yes

Reviewer #3: Yes

**********

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: No

Reviewer #2: No

Reviewer #3: No

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above and, if applicable, provide comments about issues authors must address before this protocol can be accepted for publication. You may also include additional comments for the author, including concerns about research or publication ethics.

You may also provide optional suggestions and comments to authors that they might find helpful in planning their study.

(Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: English language must be improved. Some parts of the sentences are repeating. There are so many grammatical mistakes. Some sentences aren’t understandable. Manuscript needs detailed English polishing and, in this format, it can’t be published.

Tidal Variation – short is TV not VT as it is written in study protocol. Please change accordingly.

Minute tidal variation – short is MTV no MVT as it is written in study protocol. Please change accordingly.

When you read manuscript draft it’s not clear will you use the same branded IS or different ones - please specify in text of PONE-D-23-39727_reviewer. In Spirit 2013 Checklist type of IS is specified.

Reviewer #2: This is a study protocol corresponding to a cross-over trial to compare the measurement of the distribution of pulmonary ventilation of commercial flow IS versus the low-cost MPIS. The trial is registered within clinicaltrials.gov with a specific NCT number, and has been approved by the concerned IRB/Ethics Committee. The study objectives are on target, and the study design looks adequate. However, I mostly have some concerns/comments in the statistical design and analytical framework, and CONSORT guidelines, which may require attention:

1. Methods:

Methods reporting need some work. An orderly manner is suggested, following CONSORT guidelines, without repeating information, such as Trial Design, Participant Eligibility Criteria and settings, Interventions, Outcomes, sample size/power considerations, Interim analysis and stopping rules, Randomization (details on random number generation, allocation concealment, implementation), Blinding issues, etc, should be mentioned. The authors are advised to create separate subsections for each of the possible topics (whichever necessary), and that way produce a very clear writeup. I see there is already a sincere effort. They are advised to write it carefully, following nice examples in the manuscript below:

https://www.sciencedirect.com/science/article/pii/S0889540619300010

Specific comments:

(a) For instance, the randomization and allocation concealment should be made very clear (they are NOT the same thing); the trial staff recruiting patients should NOT have the randomization list. Randomization should be prepared by the trial statistician, and he/she would not participate in the recruiting.

(b) Details on the randomization, with reference to the crossover design, is needed; just stating that randomization.com will be used to generate is not enough.

(c) I was surprized to find no justification of sample size/power in the draft; just stating that 30 subjects (15 and 15) will be recruited is a missed opportunity. There exists suggestions for constructing such numbers for pilot randomized cross-over trials: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4876429/

Sample sizes need to be presented using the primary endpoint, with mention of the desired effect sizes, and appropriate statistical tests.

2. Writing style: The writing style needs a serious facelift. Certain areas have misconstructed sentences.

3. Discussion Section: Given the study was designed based on a pilot study, the Discussion section should clearly state that the findings of this study would be only limited to the enrolled sample, and should allude to future trials with larger sample sizes (under medium to large effect sizes), and covering other populations.

Reviewer #3: Dear Sir,

First, the article needs some serious grammar, spelling, and incomplete sentences revision. But what is more important, as I understand, you will be testing the healthy volunteers. If I am not wrong, in those persons the results of EIT should be normal independently of the device used so no difference will be default result and the study can not fulfill its primary purpose of comparing the efficiency of two different devices. I would suggest comparing the effects of two different devices in the population with the respiratory problems consistent with the intended use (e.g. after thoracic surgery) in the same crossover manner but with the shorter period between the tests.

Regards

**********

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.

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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

Reviewer #3: No

**********

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Revision 1

March, 2024

Respected

EDITORIAL BOARD AND REVIEWERS

PLOS ONE

Kind regards.

Through this letter, the authors would like to confirm the receipt of the observations made by the reviewers of the article titled "Comparative analysis of pulmonary ventilation distribution between low-cost and branded incentive spirometers using electrical impedance tomography in healthy adults: Study protocol," which has been submitted for consideration in PLOS One.

We want to express our sincere gratitude for the valuable observations provided by each of the three reviewers. We believe that these observations are highly relevant and will significantly contribute to improving the quality of the manuscript, ensuring that it fulfills its objective of reporting the protocol of this clinical trial.

We are attaching three main files: the current one, which is the response to the reviewers, the revised manuscript in its clean version, and the revised manuscript with track changes.

Below, we will proceed to respond in detail to each of the observations received.

REVIEWER #1:

• English language must be improved. Some parts of the sentences are repeating. There are so many grammatical mistakes. Some sentences aren’t understandable. Manuscript needs detailed English polishing and, in this format, it can’t be published.

The authors are grateful for your feedback. We have enhanced the English language writing throughout the entire text. Furthermore, a Native North American language teacher has reviewed and edited the language for accuracy and clarity.

• Tidal Variation – short is TV not VT as it is written in study protocol. Please change accordingly.

Thank you for your observation; the corresponding adjustment has been made.

• Minute tidal variation – short is MTV no MVT as it is written in study protocol. Please change accordingly.

Thank you for your observation; the corresponding adjustment has been made.

• When you read manuscript draft it’s not clear will you use the same branded IS or different ones - please specify in text of PONE-D-23-39727_reviewer. In Spirit 2013 Checklist type of IS is specified.

Thank you very much for your observation. In section 2.6.1, the description of interventions includes the Triflo II and MPIS devices.

REVIEWER #2

This is a study protocol corresponding to a cross-over trial to compare the measurement of the distribution of pulmonary ventilation of commercial flow IS versus the low-cost MPIS. The trial is registered within clinicaltrials.gov with a specific NCT number, and has been approved by the concerned IRB/Ethics Committee. The study objectives are on target, and the study design looks adequate. However, I mostly have some concerns/comments in the statistical design and analytical framework, and CONSORT guidelines, which may require attention:

Methods:

• Methods reporting need some work. An orderly manner is suggested, following CONSORT guidelines, without repeating information, such as Trial Design, Participant Eligibility Criteria and settings, Interventions, Outcomes, sample size/power considerations, Interim analysis and stopping rules, Randomization (details on random number generation, allocation concealment, implementation), Blinding issues, etc, should be mentioned. The authors are advised to create separate subsections for each of the possible topics (whichever necessary), and that way produce a very clear writeup. I see there is already a sincere effort. They are advised to write it carefully, following nice examples in the manuscript below: https://www.sciencedirect.com/science/article/pii/S0889540619300010

The authors appreciate the observations made. We have completely restructured the methodology in terms of the distribution of each of its subchapters. This reorganization was based on the recommendations of the evaluator, the suggested article, and other protocols published in PLOS One.

Specific comments:

• For instance, the randomization and allocation concealment should be made very clear (they are NOT the same thing); the trial staff recruiting patients should NOT have the randomization list. Randomization should be prepared by the trial statistician, and he/she would not participate in the recruiting.

The researchers acknowledge and comply with the recommendations made by the evaluator. It should be noted that the randomization process will be conducted by a statistician who is not part of the research team. We have provided a more detailed description of the allocation protocol.

• (b) Details on the randomization, with reference to the crossover design, is needed; just stating that randomization.com will be used to generate is not enough.

We appreciate your observations. The process has been described in more detail.

• (c) I was surprized to find no justification of sample size/power in the draft; just stating that 30 subjects (15 and 15) will be recruited is a missed opportunity. There exists suggestions for constructing such numbers for pilot randomized cross-over trials: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4876429/. Sample sizes need to be presented using the primary endpoint, with mention of the desired effect sizes, and appropriate statistical tests.

The authors appreciate and agree with your observation. Although the sample calculation remained unchanged, we have provided a thorough explanation to justify this calculation, focusing on the type of design we are implementing.

• 2. Writing style: The writing style needs a serious facelift. Certain areas have misconstructed sentences.

The authors are grateful for your feedback. We have enhanced the English language writing throughout the entire text. Furthermore, a Native North American language teacher has reviewed and edited the language for accuracy and clarity.

• 3. Discussion Section: Given the study was designed based on a pilot study, the Discussion section should clearly state that the findings of this study would be only limited to the enrolled sample, and should allude to future trials with larger sample sizes (under medium to large effect sizes), and covering other populations.

The authors acknowledge your recommendation and have made adjustments to the discussion based on the reviewer's suggestions.

REVIEWER #3:

• Dear Sir. First, the article needs some serious grammar, spelling, and incomplete sentences revision. But what is more important, as I understand, you will be testing the healthy volunteers. If I am not wrong, in those persons the results of EIT should be normal independently of the device used so no difference will be default result and the study can not fulfill its primary purpose of comparing the efficiency of two different devices. I would suggest comparing the effects of two different devices in the population with the respiratory problems consistent with the intended use (e.g. after thoracic surgery) in the same crossover manner but with the shorter period between the tests.

The authors appreciate the recommendations and have made significant efforts to improve the entire document in terms of writing and composition. The paper was reviewed by a native North American language professor, who also edited the document to enhance its clarity and comprehension.

Regarding the target population of the protocol, the authors consider it an important recommendation, which we will apply for the design of a study involving a population with restrictive lung impairment, aiming to assess effectiveness. However, for this protocol, we continue to propose a healthy population as we intend to evaluate the device's action in a proof-of-concept phase. Hence, the selected population and sample size remain unchanged.

With these adjustments, the authors hope to meet the requirements that will allow our article to be accepted in such a prestigious journal. We will remain attentive to any requirements that may arise.

Attachments
Attachment
Submitted filename: Response to the reviewers.pdf
Decision Letter - Davor Plavec, Editor

Comparative analysis of pulmonary ventilation distribution between low-cost and branded incentive spirometers using electrical impedance tomography in healthy adults: Study protocol.

PONE-D-23-39727R1

Dear Dr. Benavides-Cordoba,

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.

An invoice will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Davor Plavec, MD, MSc, PhD, Prof.

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Dear Authors,

your manuscript is now acceptable for publication.

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Does the manuscript provide a valid rationale for the proposed study, with clearly identified and justified research questions?

The research question outlined is expected to address a valid academic problem or topic and contribute to the base of knowledge in the field.

Reviewer #1: Yes

Reviewer #2: Partly

**********

2. Is the protocol technically sound and planned in a manner that will lead to a meaningful outcome and allow testing the stated hypotheses?

The manuscript should describe the methods in sufficient detail to prevent undisclosed flexibility in the experimental procedure or analysis pipeline, including sufficient outcome-neutral conditions (e.g. necessary controls, absence of floor or ceiling effects) to test the proposed hypotheses and a statistical power analysis where applicable. As there may be aspects of the methodology and analysis which can only be refined once the work is undertaken, authors should outline potential assumptions and explicitly describe what aspects of the proposed analyses, if any, are exploratory.

Reviewer #1: Yes

Reviewer #2: Partly

**********

3. Is the methodology feasible and described in sufficient detail to allow the work to be replicable?

Descriptions of methods and materials in the protocol should be reported in sufficient detail for another researcher to reproduce all experiments and analyses. The protocol should describe the appropriate controls, sample size calculations, and replication needed to ensure that the data are robust and reproducible.

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors described where all data underlying the findings will be made available when the study is complete?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception, at the time of publication. 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: Yes

**********

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: No

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above and, if applicable, provide comments about issues authors must address before this protocol can be accepted for publication. You may also include additional comments for the author, including concerns about research or publication ethics.

You may also provide optional suggestions and comments to authors that they might find helpful in planning their study.

(Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: In abstract in front of EIT full name should be written (Electrical Impedance Tomography ).

Authors have implemented all suggested changes.

English language has been improved.

Reviewer #2: The authors addressed my previous round of comments with significant satisfaction. I have no further comments.

**********

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

**********

Formally Accepted
Acceptance Letter - Davor Plavec, Editor

PONE-D-23-39727R1

PLOS ONE

Dear Dr. Benavides-Cordoba,

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now being handed over to our production team.

At this stage, our production department will prepare your paper for publication. This includes ensuring the following:

* All references, tables, and figures are properly cited

* All relevant supporting information is included in the manuscript submission,

* There are no issues that prevent the paper from being properly typeset

If revisions are needed, the production department will contact you directly to resolve them. If no revisions are needed, you will receive an email when the publication date has been set. At this time, we do not offer pre-publication proofs to authors during production of the accepted work. Please keep in mind that we are working through a large volume of accepted articles, so please give us a few weeks to review your paper and let you know the next and final steps.

Lastly, if your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

If we can help with anything else, please email us at customercare@plos.org.

Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Dr. Davor Plavec

Academic Editor

PLOS ONE

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