Dear Dr. Khan,

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Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

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

Reviewer #1: Yes

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

Reviewer #1: Yes

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

The PLOS Data policy

Reviewer #1: Yes

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

Reviewer #1: Yes

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Reviewer #1: The authors studied trends, district-level variations, and socioeconomic disparities in cesarean section delivery and its association with neonatal mortality in Bangladesh. Some suggestions were listed as follows:

1. In the Statistical Analysis Section, “We employed multilevel mixed-effect binary logistic regressions to investigate factors associated institutional delivery, CS delivery at the population level, and CS delivery at the institutional level.” Can you provide the statistical equation? How can you explain CS delivery at the population level, since we know that the mixed-effect model is the individual level model?

2. In Table 3, some of the cell frequency is zero; this zero is observed rather than structural; this is observed zero. Could you offer us the confidence interval so we can use small sample inference to estimate the confidence interval?

3. What is the interpretation of R^2=0.2286 in Figure 1?

4. In Table 4 and Table 5, the authors presented the results of mixed effect models. Can you clearly specify what the random effect terms are? Have you only used random intercepts? Could you please provide the value and interpretation of the standard error of random effect terms?

5. How did the mixed effect approaches address changes in CS delivery rate during survey years?

6. How did the mixed effect approaches address changes in neonatal mortality rate during survey years?

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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

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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.

Dear Dr. Khan,

In BDHS surveys, the sample size was calculated to get reliable estimates at the division level but not at the district level. I wonder how the authors can make sure that the district level estimates are reliable. 

Secondly, how did the authors implement the complex survey design in the multilevel modelling exercise? Please detail out this in the statistical analysis section. 

Please submit your revised manuscript by Feb 28 2025 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.

• 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: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols . Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols .

We look forward to receiving your revised manuscript.

Kind regards,

Mohammed Moinuddin, PhD

Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

Reviewer #3: (No Response)

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

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: No

**********

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

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: No

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

The PLOS Data policy

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

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

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: No

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Reviewer #1: (No Response)

Reviewer #2: Table 2: Quintile analysis would be understandable if calculated with in 100% for all per category.

As this manuscript has data for each district on cs% so low CS rate districts are need to take into consideration for policy making, This should come into conclusion

Just a statement: There are a number of papers published on trends, deteminants, and risk factors using BDHS data. These are already known. Now paper need how to optimize the CS rate in Bangladesh

Reviewer #3: 1) The manuscript partially address the review comments and still require significant improvement in terms of scope of the study, methods, and results interpretation.

2) They estimated proportion of CS for different strata for survey years, for example–Private healthcare facilities, and interpreted as "Private healthcare facilities contributed 84% of the total CS deliveries in 2022, a marked increase from 45.5% in 1999/2000", which is completely wrong interpretation. You cannot estimate contribution of a factor just by estimating prevalence. Be careful about it.

3) The data highlight an overrepresentation of CS delivery in private facilities, but the study does not deeply explore the drivers behind this trend.

4) Although sampling weights were applied, the clustering of data within districts or divisions may introduce sampling bias, especially in areas with smaller sample sizes.

5) The time intervals between BDHS surveys (three to five years) may obscure shorter-term trends or fluctuations in CS delivery rates.

6) The study does not differentiate between medically necessary and unnecessary CS deliveries, which limits the interpretation of whether the observed trends align with maternal and neonatal health needs.

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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: Yes:  Md. Kamruzzaman, PhD

Reviewer #2: Yes:  Aminur Rahman Shaheen

Reviewer #3: No

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[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.

Trends, District-Level Variations, and Socioeconomic Disparities in Cesarean Section Delivery in Bangladesh

PONE-D-24-11488R2

Dear Dr. Khan,

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,

Rajib Chowdhury, M.Sc.; MPH

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

Reviewer #1: All comments have been addressed

Reviewer #4: (No Response)

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

Reviewer #1: Yes

Reviewer #4: Yes

**********

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

Reviewer #1: Yes

Reviewer #4: Yes

**********

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

The PLOS Data policy

Reviewer #1: Yes

Reviewer #4: Yes

**********

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

Reviewer #1: Yes

Reviewer #4: Yes

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Reviewer #1: All comments have been addressed, and I do not have any further suggestions. Therefore, I believe the manuscript is now ready for acceptance and publication.

Reviewer #4: Dear Authors,

Thank you for carefully addressing the points raised in the previous review. The revised manuscript is now technically sound, clearly written, and entirely consistent with PLOS ONE’s publication criteria. The use of multiple rounds of nationally representative BDHS data, district-level mapping, and multilevel regression provides a comprehensive and credible picture of cesarean section trends, regional heterogeneity, and socioeconomic disparities in Bangladesh.

The revisions have enhanced the clarity of the Methods, the contextualization of the WHO benchmark, and the interpretation of trends between private and government facilities. The supplementary materials are also well organized and support the main findings.

At this stage, I have no further substantive comments to make. Only minor editorial refinements (shortening a few long sentences for flow) might be considered during final preparation, but these are not essential.

Overall, this is an important, rigorous, and policy-relevant contribution to the maternal health literature. I recommend acceptance of this manuscript.

Kind regards,

Sadık Kükrer, M.D., MSc.

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what does this mean? ). If published, this will include your full peer review and any attached files.

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Reviewer #1: Yes:  Md. Kamruzzaman, PhD

Reviewer #4: Yes:  Sadık Kükrer, M.D., MSc.

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