PONE-D-20-19678

Short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in Ethiopia. A systematic review and meta-analysis:

PLOS ONE

Dear Dr. Damtie,

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 Nov 16 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:

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We look forward to receiving your revised manuscript.

Kind regards,

Mohammad Rifat Haider, MBBS, MHE, MPS, PhD

Academic Editor

PLOS ONE

Additional Editor Comments:

Take care of the reviewers' comments. Put special emphasis on the English language and grammar.

Journal Requirements:

When submitting your revision, we need you to address these additional requirements.

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

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https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf

2. Thank you for including the statement that "The database search was conducted on 'The searching of research articles was carried out from April 1 up to May 30, 2020, and articles published until May 30, 2020, were included in the review.' Please revise this statement to clarify whether all databases were searched from inception, or if there were any limits placed on the publication dates in your search.

3. At this time, we ask that you please provide the full search strategy and search terms for at least one database used as Supplementary Information.

4. Please provide the results of the assessment of publication bias conducted in the meta-analyses. Please provide the funnel plots of the Egger's regression test as a separate Figure in your manuscript.

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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: 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: 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: No

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: I thank the editors for the opportunity to review this manuscript. Short birth spacing is a major cause of morbidity among children and women from low- and middle-income countries, and it has a large impact in Sub-Saharan countries. Although the topic is highly relevant, major changes to the manuscript are required.

A significant limitation of the manuscript in its current form is the English. There are many mistakes and inconsistencies that require an urgent revision by a professional copyeditor. The mistakes make the manuscript challenging to read and understand.

Abstract

- in methods: “and determinants of birth spacing in Ethiopia...” is not true. The researchers prespecified the factors they explored. Please clarify.

- results: please describe the number of articles included in the review and in the meta-analyses.

- conclusion: "The practice of short birth spacing in Ethiopia was higher." Please elaborate on this phrase.

Introduction

- Given the considerable number of factors associated with short birth spacing, it is not clear why the authors chose to explore only maternal education, contraceptive use, and duration of breastfeeding. Please clarify what criteria were used to choose the aforementioned factors.

Methods

- Line 95: “Grey literature was identified through the input of content experts.” It is not clear who these experts were and how they were selected and/or approached. Moreover, it is not clear how many studies the experts included and what criteria was used to select the studies.

- Lines 99 to 105: the authors should include the exact search they used in the different databases. A list of terms is not enough. Moreover, please consider uploading the search as an additional file as this will save space.

- Line 105: “This systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) checklist.” The PRISMA checklist is preferred for systematic reviews and meta-analysis of experimental studies. The MOOSE guideline is preferred for Meta-Analysis of Observational Studies in Epidemiology (doi:10.1001/jama.283.15.2008). Please refer to the MOOSE reporting guidelines and use them to report the findings of your article.

- Inclusion criteria: the review is supposed to be focused only on studies exploring maternal education, contraceptive use, and duration of breastfeeding. However, this is not reflected in the inclusion criteria. Please clarify.

- Study setting: I suggest the authors to move this information to the introduction.

- Outcome measurement: There will be many different definitions or cut-off points among the three factors that the authors wanted to explore in their systematic review. For example, the authors will find studies exploring duration of breastfeeding with cut-off points of 6, 8, 12, 18, and 24 months. It is not clear why the authors pre-specified their cut-off point to be 24 months. Moreover, it is not clear why the authors pre-specified their education contrast to be formal education vs no formal education, or contraceptive use yes vs no. Pre-specifying these contrasts would exclude many articles. This should be explained in the limitations section. Additionally, this information is not explained in the inclusion criteria. Please clarify.

Results

- The authors reported high heterogeneity among the included studies. Why did the authors decide to conduct meta-analysis instead of providing a narrative synthesis of the results? Please clarify this sensitive issue.

- From the first paragraph of Results, it seems that the authors conducted a two-step screening phase. First, they screened the titles, and second, they screened the abstracts of the publications. In systematic reviews, however, titles and abstracts are evaluated together. I believe that screening the references in the way the authors did could introduce major biases in the review results. Please explain the rationale behind the two-step screening process.

- First paragraph of Results: the authors overexplain the flow diagram of the articles screened/included. This information could be easily summarized in Figure 1.

- In lines 181 to 184, the authors say that they included 7 studies in the meta-analysis. It is not clear why the authors included only these 7 studies from the original 9 included studies. More concerning, in lines 189 and 190 the authors mention that they included 6 articles, not 7. This issue needs clarification.

- The authors included only three studies in the meta-analysis related to breastfeeding. In the limitations, please explain the limitations of conducting meta-analysis with low numbers of studies.

Discussion

- Lines 228 & 229, and 247 & 248: there is no need to repeat the objective of the study.

- Line 241: “a subgroup analysis was done by residence (both urban and rural versus rural)” It is not clear to me why the authors decided to explore this contrast. Why not to simply explore urban vs rural? Please clarify.

- Lines 249 to 251 and 265 to 258: there is no need to repeat the results of the study.

Conclusion

- “Based on the finding, the Ethiopian government should improve the existing family planning program for all women of childbearing age.” Given the considerable limitations of this meta-analysis, I believe the authors are overstating their conclusion. Please adjust in light of the limitations of the study.

Reviewer #2: General comments: This is an important review aimed at estimating the pooled prevalence of short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in. However, a number of issues need attention before acceptable for publication.

ABSTRACT:

Objectives: This is Ok.

Methodology: The authors should include the key words used in the search.

The authors should state the selection criteria.

The authors should state the outcome measures assessed.

The authors should state the subjects of the studies they included in the meta-analysis.

The authors should state which outcomes were analysed.

Main results: The authors should state the number of studies assessed, identified and how many were included in the meta-analysis. What were the results of heterogeneity across studies?

CONCLUSION

Why did the authors state that: “The practice of short birth spacing in Ethiopia was higher.?’

The authors should rephrase their conclusion because the practice of short birth spacing in Ethiopia cannot he said to be higher.

The authors should avoid 'slangs' in their writing like ‘didn’t’.

INTRODUCTION:

Although, this is well written; however, the introduction needs brushing up of language and beefing up the justification for the study.

MATERIALS AND METHODS

Why did the authors exclude relevant articles with full texts of which unavailable after two email contacts of the corresponding authors?

RESULTS

In table 1, why was the prevalence of the last three publications not included?

DISCUSSION

The authors must correct the typo errors and other errors in the manuscript. The authors need English language editor.

The authors should discuss the clinical implications of their study findings.

The authors should also discuss the strengths of their study.

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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: Yes: George Eleje

[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-20-19678R1

Short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in Ethiopia. A systematic review and meta-analysis:

PLOS ONE

Dear Dr. Damtie,

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 take care of the reviewer's comment.

Please submit your revised manuscript by Dec 22, 2020. 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,

Mohammad Rifat Haider, MBBS, MHE, MPS, PhD

Academic Editor

PLOS ONE

Additional Editor Comments (if provided):

Please take care of the reviewer's comment.

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

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: All comments have been addressed

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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: 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. 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 authors have addressed all my comments. There are still a few English mistakes. For example, "Short birth spacing had been linked" (line 63) -> has been linked. "Data source and searching strategies" (line 107) -> search strategy. I suggest the authors use a professional editing service to fine tune the manuscript.

Reviewer #2: The authors have addressed the issues adequately. This is a systematic review aimed at estimating the pooled prevalence of short birth spacing and its association with contraceptive use, educational status, and duration of breastfeeding among

reproductive-age women in Ethiopia.

Title: This is OK.

Regarding the English language, the authors have endeavored to work on it.

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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: Yes: Juan Pimentel

Reviewer #2: Yes: George Eleje

[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.

Short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in Ethiopia. A systematic review and meta-analysis:

PONE-D-20-19678R2

Dear Dr. Damtie,

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 for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, 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,

Mohammad Rifat Haider, MBBS, MHE, MPS, PhD

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

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 #2: All comments have been addressed

**********

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 #2: Yes

**********

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

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 #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 #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 #2: The revised version has been well received. The corrections are clearly marked in track changes format. The authors have addressed the comments satisfactorily.

**********

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 #2: Yes: George Eleje