PONE-D-21-10805

Prediction of odds for emergency cesarean section: a secondary analysis of the CHILD term birth cohort study

PLOS ONE

Dear Dr. Mandhane,

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.

Please submit your revised manuscript by Aug 15 2021 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.

Kind regards,

Eduardo Ortiz-Panozo, MD; MSc

Academic Editor

PLOS ONE

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2. Thank you for including your ethics statement: "Ethics approval was obtained from local authorized review board of each CHILD study center and McMaster University. A separate ethics approval was obtained for this secondary data analysis (Pro00092920)." 

a) Please amend your current ethics statement to include the full name of the ethics committee/institutional review board(s) that approved your specific study. 

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Additional Editor Comments:

Since the study aims at developing a prediction model, I suggest to include a table showing the final model's regression coefficients plus the intercept. Not as a supplementary table (i.e, Supplementary table 3) but as part of the main analysis.

Please clarify how many and what variables were tested as potential predictors. What were the p-values for excluded variables?

Authors mention Table 3a and a scoring system in the text, but I could not find those results in tables.

I would suggest to include more statistical measures of the predictive capacity of the model. Is it possible to calculate diagnostic accuracy, sensitivity, specificity, PPV, NPV and/or diagnostic likelihood ratios?

It would be important that authors discuss about the differences between the models for nulliparous and multiparous and their implications. From their estimated coefficients, it seems like they only differ in the role of hypertensive disorders of pregnancy and (obviously) previous vaginal delivery.

The model is of limited utility for settings where there is no information on CES-D. Since most likely this would be the case for most situations, I suggest to run separate models without this variable.

How these results compare to other prediction model? I would suggest to comment about the WHO predictions models, such as C-Model by Souza et al.

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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?

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: Partly

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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: Yes

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4. 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

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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: The manuscript is relevant and reaches conclusions according to the objectives, but there is a lack of attemption to the analgesic modalities during labour and about the epidural rates. I think it is a very important issue when you are affording CS rates. Statistical analysis has been correctly performed and statistical material has been provided properly. The manuscript is written in correct english, as far as I know (I'm not native english speaker).

The authors should include details about analgesia during labour, epidural rate, and motor block, or at least to detail the epidural analgesic protocol that has been used in this cohort of women.

Reviewer #2: This is an interesting study.

However,

1. Some grammatical etc. errors should be corrected. Examples:

Line 110/Please change “earlypregnancy” to “early pregnancy”

Line 119/Please change “cephalopevlic” to cephalopelvic” (using the advantage of automatic corrections).

2. In the “conclusion”, a real conclusion is expected (and not a detailed iteration of the title).

3. To take advantage of the practical benefits of similar studies, it should be clarified:

a) the indications of emergency CS (ECS)

b) the necessary steps to avoid situations leading to ECS

4. A working calculator could convince that the whole effort is a useful tool to justify or avoid ECS.

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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

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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.

PONE-D-21-10805R1

Prediction of odds for emergency cesarean section: a secondary analysis of the CHILD term birth cohort study

PLOS ONE

Dear Dr. Mandhane,

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.

Please submit your revised manuscript by Mar 25 2022 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: 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,

Eduardo Ortiz-Panozo, MD; MSc

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

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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 #3: (No Response)

Reviewer #4: (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 #3: Partly

Reviewer #4: Yes

********** 

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

Reviewer #3: Yes

Reviewer #4: 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 #3: No

Reviewer #4: 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 #3: Yes

Reviewer #4: 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 #3: Overall, this study was interesting as they had a large number of samples and a combination of obstetrics and non-obstetrics factors counted for emergency cs prediction tools. However, there are a few things that could be added to improve the quality of the study.

In general, it was suggested to use appropriate written English language. Many paragraphs were considered not effective as repetitive words and redundant sentences were found.

- Abstract:

Keywords: antenatal depression?

Higher AUC in validation set?

Conclusion: Maybe you could paraphrase?

- Introduction

No reference 1? The reference started with number 2

Line 64-66, 66-68: please paraphrase

- Methods & Results

When dividing the data? After recruitment or after applying exclusion criteria? Please specify with number too

The division of training and validation set (80% and 20%) was based on what?

The use of CESD in methods, please put a reference

Diagnosis criteria for hypertensive disorder and diabetes mellitus complicating pregnancy? please put reference too

The Adjusted OR, please specify, adjusted with what?

- Analysis:

This study focuses in comparing vaginal birth and emergency cs. Since you put scheduled cs in the table 1, why don’t you also compare the scheduled cs and the emergency cs? The findings might be interesting and can be added in the discussion too.

- Discussion:

Please add discussion to compare other studies for emergency cs scoring systems. Not only study for cs prediction in general. Such as a current previous study which develop a scoring system for emergency cs by maternal-fetal perinatal characteristics. Although that one was different from yours, maybe you can add this in the discussion.

Typo: Line 144, 155, 249

- Reference:

A number of references were considered too old, there are many newer references that could be used related to the issue

- Supplementary materials:

Table 1: acupressure? Reference?

Table 2 in supplementary files similar to Table 1 in the manuscript? No need to mention it in supplementary files.

Reviewer #4: I have participated in the review process only in this final round. My feeling is that authors have addressed the comments of the reviewers, although I would defer to them in the decision on to what extent it has been achieved. My only suggestion would be the following: the authors have done a good job attending the reviews, especially the one related to the comparison with other tools predicting the risk of C-Section. However, I think it is still possible in the discussion to stress what are the advantages of this tool. The authors must make a strong case for why this new tool is necessary, and the advantages of using this one instead of other existing tools up front.

********** 

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 #3: Yes: Rima Irwinda

Reviewer #4: Yes: BERNARDO HERNANDEZ PRADO

[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-21-10805R2Prediction of odds for emergency cesarean section: a secondary analysis of the CHILD term birth cohort studyPLOS ONE

Dear Dr. Mandhane,

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.

 I apologize for the length of time that it is taking to process your manuscript. The COVID-19 pandemic has slowed our process considerably by affecting availability and response of reviewers. See Additional Editor Comments below.

Please submit your revised manuscript by May 15 2022 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: 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,

Eduardo Ortiz-Panozo, MD; MSc

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

Additional Editor Comments (if provided):

In my view, authors have addressed all reviewers' comments. Lastly, I would request authors to comment on the implications of their tool's low sensitivity in the discussion. Does that mean the tool works better as a "rule-in" rather than a "rule-out" test? And if so, do the relatively high AUC and accuracy result not from identifying (predicting) those who need an emergency CS but those who would not need one?

Please also confirm that PPV in the validation sample is 63% (Table 2).

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Reviewers' comments:

[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.

Prediction of odds for emergency cesarean section: a secondary analysis of the CHILD term birth cohort study

PONE-D-21-10805R3

Dear Dr. Mandhane,

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.

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Kind regards,

Eduardo Ortiz-Panozo, MD; MSc

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments: