PONE-D-24-13717Folic acid supplementation during preconception period in sub-Saharan African countries: A systematic review and meta-analysisPLOS ONE

Dear Dr. Aweke,

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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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.

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Jai K Das

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?

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: Partly

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

Reviewer #1: Yes

Reviewer #2: Yes

**********

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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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: 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 under review addresses a critical question of folic acid supplementation in sub-sharan Africa. The methodolgy, analysis and results are relevant, however, the paper requires careful reconsideration and possibly re-writing the introduction and the discussion sections to strengthen the manuscript. Some specific points to consider are highlighted below:

Abstract:

1. Add the number of studies and participants included in the review in the results section of the abstract.

Introduction:

1. NTDs has been spelled out more than once. Spell out once when used for the first time and then use the acronym for the rest of the manuscript.

2. Some of the references in the introduction are very old. I suggest replacing these with the more recent references.

3. I found the introduction very weak. There are quite a few recent relevant references assessing the existing evidence, guidelines, and policies around folic acid supplementation. I suggest that the authors look at these papers and add some of the relevant references in their introduction to make a stronger case for the review:

- Quinn M, Halsey J, Sherliker P, Pan H, Chen Z, Bennett DA, Clarke R. Global heterogeneity in folic acid fortification policies and implications for prevention of neural tube defects and stroke: a systematic review. EClinicalMedicine. 2024 Jan 1;67.

- Viswanathan M, Urrutia RP, Hudson KN, Middleton JC, Kahwati LC. Folic acid supplementation to prevent neural tube defects: a limited systematic review update for the US preventive services task force.

- Barry MJ, Nicholson WK, Silverstein M, Chelmow D, Coker TR, Davis EM, Donahue KE, Jaén CR, Li L, Ogedegbe G, Rao G. Folic acid supplementation to prevent neural tube defects: US Preventive Services Task Force reaffirmation recommendation statement. Jama. 2023 Aug 1;330(5):454-9.

- De‐Regil LM, Peña‐Rosas JP, Fernández‐Gaxiola AC, Rayco‐Solon P. Effects and safety of periconceptional oral folate supplementation for preventing birth defects. Cochrane database of systematic reviews. 2015(12).

4. Add some references (if available) on country specific prevalance rates of NTDs in Africa.

5. The acronym for sub-sahraan Africa (SSA), folic acid (FA) and low- middle- income countries (LMICs) have been used inconsistently throughout the manuscripot. I would suggest that the authors spell it out when used for first time in the darft and then consistently use the acronym throughout.

Methods:

1. Not sure what this sentence under 'study selection' means: "articles examining the prevalence and determinants of folic acid supplementation during preconception period was gathered from various". From the objectives and results, it seems that only prevalance was assessed. I am not sure whether the authors ahve also looked at the determinants? and if they have, this has not be reported anywhere in the draft.

2. Not sure what this sentence means: "A quantitative cross-sectional study design was employed to enhance clarity and significance." Do you mean that the eligibility for study selection was cross-sectional study design? If yes, then state this clearly.

3. Suggest authors add a table or a figure depicting the regions and the respective countries included in sub-saharan Africa. It would add clarity for the readers as teh regions and respective countries have been disucssed and analysed in the resultss and discussion sections.

4. Studydesign is stated twice under data extraction.

Results:

1. I cant see the full characterictis of the inlcuded studies table (probably because it was in a landscape mode) so I am not sure if my comments are relevant. But I would suggest that the authors delete the columns on study period, center, sampling method, and response rate. I would also suggest that the authors add the columns on sample size and study results (reported prevalance) in the study characteristics table.

2. I would suggets that the authors remove the study quality column from the study characteristics table and add a separate section on study quality.

Discussion:

I would suggest that the authors re-organise the discussion section starting with summarising the reveiw findings, quality of the included studies, comparing the review findings with other studies/reviews, strengths and limitations of the review and research and practice implications.

I would suggest that the authors compare the study findings with studies conducted in similar context. For eaxmple, reference 59 is a study from Italy and hence widely differs in context. However, authors can broadly discuss the differences in the folic acid supplementation prevalance between high income and low- middle- income countries.

Reviewer #2: Thank you for giving me the opportunity to review your paper. I think you paper requires thorough read. Methodology is not clear, few sentances are repetitive, there are grammatical errors and information looks scattered.

Abstract:

Introduction:

Seems very long for an abstract.

Just a suggestion: instead of reporting global estimates of NTDs I would suggest writing the estimates from Sub Saharan Africa.

I dont think daily dosage is required here.

Methods:

Please add on what type of studies did you include? Last date of search? if GRADE was conducted and how was quality of included studies conducted (if you did any of these)

Results:

Line 44: not sure what do you mean by 'individual studies' here.

Line 46: subgroup analysis based on?

Line 49: remove double brackets from the end

Quality of included studies in missing

Introduction

If you have introduced the abbreviation once, then you dont have to introduce it again and again. e.g., NTDs.

Methods:

I would suggest to rearrange some headings. After registration, you should talk about the eligibility criteria and then search strategy and study selection and so on.

Line 117: you have stated that you search institutional repositories. Please state which were those?

Line 120: Please check punctuation: "supplementation, and folic acid administration. folic acid adherence, folinic acid, and vitamin B9."

Line 127-129: This sentence is very vague "A quantitative cross-sectional study design was employed to enhance clarity and significance'

Line 127: 'omitted' is not an appropraite word to use here

I think you need to revisit this paragraph. It requires language editing

Linme 127-129: " A quantitative cross-sectional study design was employed to enhance clarity and significance. In contrast, studies utilizing qualitative methodologies were omitted due to the specific nature of the review and the analytical approach selected for this review" I think this should be discussed under section 2.4.

Line 131: I understand you used RAYYAN then why did you exported data on Endnote?

Section 2.3 says study selection but it doesnt talks clearly about it. You have not written about title/abstract and full text screening. How conflicts were managed? Lacks lot of important information.

Section 2.4: A lot of important information is missing. I am confused. Did you include cross sectional studies and grey literature or only cross sectional studies.

Line 136: better to use the word 'included' rather than incorporated.

Suggest adding a Table on PECO criteria

Line 146: suggest using the word 'resolved' instead of 'fixed'

Line 153 and 155: please avoild using such vague words/phrases: 'the required information' 'important parameters'

Line 157: study setting in repeated twice

Line 156: If you are only including cross-sectional studies then why are you collecting data on study designs.

Line 162: Add reference of Stata

Line 166-168: The sentances are repetitive.

A lot of missing information in methods sections: did you conduct cross-referencing. did you felt need of contacting authors for missing data. You stated that you searched institutional website there is no mention of inclusion of reports in the eligibility criteria.

Why did you not assess the quality of evidence using GRADE?

On what basis did you conduct the sensitivity analysis? high heterogeneity or low quality of studies? How did you "assess the influence of individual studies on pooled estimates"?

Results:

Please Format your headings: "3.1 selection and Identification of studies"

Why did you exclud study based on poor quality? You could have done a sensitivity analysis for it

Line 198: spell out 2. Suggest spelling out numbers <10

Please dont use the word 'individual studies'.. you can say 'included studies'

Table 1 doesn't fit the page and is not clear. what does NS mean? what is R. rate? response rate?

Not sure why did you do subgroup analysis based on study period? What would you get from it?

Quality of included studies MISSING! in text.

Discussion:

I would suggest that you should summarise your study findings in the first para and then discuss about other studies

Lines 270-274: Can be moved later in the discussion under strengths.

Lines 289-291: not sure why are you comparing prevalence of Italy with your results? There is no link. These are two different regions/countries. You can compare with LMICs buy why with Italy?

You have not discussed on how quality of studies can affect the findings of your study?

Conclusion would come after limitations and strengths

Figure 1:

Why were studies excluded based on title and abstract twice?

General Comments:

Did you find studies on peri-conception? if yes, then I would suggest doing a subgroup analysis based on preconception and periconception supplementation.

Why did you included studies on pregnant women when you intention was preconception? Did they collect reterospective data?

What were the ages of the included participants? suggest doing a subgroup analysis bases of age and see the prevalence in young people

Did you do sensitivity analysis based on low quality of studies? if not then suggest doing that too.

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Reviewer #1: No

Reviewer #2: No

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PONE-D-24-13717R1Folic acid supplementation during preconception period in sub-Saharan African countries: A systematic review and meta-analysisPLOS ONE

Dear Dr. Aweke,

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 Oct 21 2024 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,

Jai K Das

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: (No Response)

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: Partly

Reviewer #2: Partly

**********

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: No

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 review title and objectives suggest that the authors aimed to review the prevalance of folic acid supplementation during preconception period which is defined as the period of time before pregnancy occurs. However, the authors have used terms for 'periconception' as well in their search strategy. Moreover, the included studies had a variety of target population "eight studies (28.57%) were women of childbearing age, 16 studies 257 (57.1%) centered on pregnant mothers, and four studies (14.3%) included postnatal mothers." Majority of these studies (16 studies) included pregnant women and does not follow the eligibiltiy crirteria for inclusion which is preconception supplementation. The only studies eligible for inlcusion as per the authors eligibility criteria are studies that targeted either women of reproductive age or postnatal women. I would suggets that the authors clarify the definition of "preconception" used for this review to reflect the correct eligibility and inclusion.

Reviewer #2: Manuscript require thorugh read anf formatting edits. There are places were there is no space between text, references, and brackets e.g., Line 108: individuals(7).The ; Line 82: In sub-Saharan Africa(SSA).

Punctuation is not used appropriately e.g. like 127: .(28). - Remove extra full stops where evere required.

Please read your manuscript thoroughly and make the required edits where necessary.

Abstract:

Introduction is still very long. Please reduce some text

- Line 31: Remove extra brackets and full stop

- Line 40: Add space between of and FA

Line 152: This line is very confusing where you say that you are including ALL journal articles. However you are excluding qualitative studies. I get what you are trying to say here but its still very confusing. "We included all types of studies published as journal articles, theses, and dissertations without imposing restrictions based on publication date or age criteria."

Section 2.2 (Line 150): First write what was included and then write what was excluded. This brings more clarity.

line 149: Which quantitative studies did you include? please state. List all the study designs which you intended to included and in results you can state that you only found cross-sectional studies

Section 2.3:

- Line 164: "were taken" is not an appropriate work to use here

- In this section first talk about making the search strategy by using Mesh terms and key words. Then talk about databases searched

Section 2.4:

Line 176: Unclear

Line 177: "The search was not constrained by the publication year; hence, articles published until January 2024, were considered for review eligibility." You have already mentioned the last publication date in section 2.3. The remaining details on restrictions should be moved to section 2.3.

Line 180: The information is not making any sense to me. As 'systematic review" everything should be done systematically. Even contacting authors comes after data extraction. Not before screening. Please read some good published systematic reviews and suggest rewritting your methodology.

Line 186: This should come before title abstract screening.

Section 2.6 will come before 2.5

Section 2.6:

Did you summarise data in Excel or you conducted data extraction in excel? Please clarify

Did you cross-reference studies for missing studies?

Through NewCastle you assess the quality of included studies. Through GRADE you assess quality of evidence. both are two different things. However, I would suggest to use GRADE. Let us know if you dont have the capacity to do GRADE.

Results:

Line 231: "We reviewed the full texts of the remaining 195 articles for eligibility, 163 studies were not eligible, and 32 studies were identified." what do you mean by 32 were identified?

- Rephrase line 238

- Line 259: I think it should be table 2?

Please place all the tables appropriately.

Table 2: Suggest showing this in a graph and move table 2 to supplementary file.

Table 3: You said that you included pregnant women because they reterospectively collected data then how are those cross-secrional studies. wont those be reterospective cohort studies? Or these were cross-sectional who collected data based on recall. I just want to have an understanding on what type of studies were these.

- You are talking about sensitivity analysis in Section 3.5 and then the actual analysis comes in Section 3.7. I would suggest moving Section 3.7 to Section 3.5

- Line 357-360: There is no connection of discussing quality of studies of your review after discussing the intervention from existing evidence. Suggest moving it afetr line 341 and try to be more cohesive.

- Line 361: I think you discussion need more working. First, Talk about the evidence coming from you study, including the subgroup, sentivity and quality of studies. then compare with other studies conducted in Africa followed by studies conducted in LMIC and HIC countries. Then talk about stengths and limitations.

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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.

PONE-D-24-13717R2Folic acid supplementation during preconception period in sub-Saharan African countries: A systematic review and meta-analysisPLOS ONE

Dear Dr. Aweke,

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 Dec 26 2024 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,

Jai K Das

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:

I would like to thank the authors for conducting this systematic review and thoroughly revising the manuscript based on the feedback from the reviewers. I have some additional concerns which are stated below:

Please specify that in the methods and results that studies done on pregnant women were only included if they had taken folate during preconception and also clarify that the studies only included these women or was there a mix.

I would suggest not to use the word ‘prevalence’ and rather use ‘proportion’ as there were studies included which were conducted in facilities and did not have a sampling frame to assess prevalence and even a few community studies would have done so. The authors need to define whether the studies covered few geographic locations or were nation level.

The introduction is lengthy and should be shortened

In the results and the PRISMA diagram – specify that how many studies were included from grey literature

Specify how many authors were contacted for missing information

Why two studies reporting zero prevalence were excluded from the analysis as they have reported the proportion, and this can add to the meta-analysis. If there is any specific reason, then the authors should state that.

In the table of included studies – please also specify the scale of the included studies – whether from one village, district, province or national and if from facilities – then how many facilities were covered.

Can the authors add a sub-group by urban/rural

Please thoroughly check the manuscript for language and grammar

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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: (No Response)

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: Yes

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6. Review Comments to the Author

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Reviewer #1: The authors have responded to the concerns raised over the last two rounds of review. I am happy with the editors recommendations if authors can make the edits to the eligibility criteria specifying that only data from studies where outcomes were specific to preconception supplementation were included. As the readers might get a bit confused looking at the 'participants' column in the characteristics studies.

Reviewer #2: Minor:

Table 1: add brackets around C after Comparison

Line 188: remove extra full stops.

Line 187: 'data' should be in lowercase

Check spacing: sampling method(random/non-random)

Table 5: I did inquire initially about using Gradepro for GRADE. I would suggest giving low/moderate/serious etc ranking for each domain and providing the explanation of each ranking as footnotes.

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Reviewer #1: No

Reviewer #2: No

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PONE-D-24-13717R3Folic acid supplementation during preconception period in sub-Saharan African countries: A systematic review and meta-analysisPLOS ONE

Dear Dr. Aweke,

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 Feb 05 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.

Please include the following items when submitting your revised manuscript:

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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,

Jai K Das

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:

i would like to thank the authors for the revisions. I have one remaining comment about the three studies reporting zero prevalence being excluded from the analysis.

The authors should either exclude these studies altogether from the review or give the reason in the manuscript for not including them in the meta-analysis and if folic acid (FA) intake wasn’t the main focus of these studies, then why were they included. Also I am not clear how the authors assessed if the sample size and the methods used in these studies were not accurate (as the Newcastle-Ottawa Scale ratings do not suggest so) and how was this ascertained for all the studies that were included. i did have a look at it and did not see any compelling issues as preconception care was assessed in these studies and IFA was one component assessed. Please elaborate on this.

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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-24-13717R4Folic acid supplementation during preconception period in sub-Saharan African countries: A systematic review and meta-analysisPLOS ONE

Dear Dr. Aweke,

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 would like to thank the authors for all the hard work and making the revisions and addressing most comments but I taking am still not clear on why the three studies with zero-prevalence are being excluded as the reasons that 'primary focus was not on folic acid (FA)' and a 'minor component' are not strong enough reasons as previously they were included in the review though not in meta-analysis. Also the exclusion criteria of your review does not specify exclusion on these reasons. The quality assessment done by the authors for the three studies is also not very different from the other studies and especially the domain of 'Assessment of outcome'. So I would suggest to include these three or provide a strong reason (within the pre-set exclusion criteria) and how it varies from all the other included studies.     

Please submit your revised manuscript by Feb 13 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.

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,

Jai K Das

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.

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

[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.

Folic acid supplementation during preconception period in sub-Saharan African countries: A systematic review and meta-analysis

PONE-D-24-13717R5

Dear Dr. Aweke,

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,

Jai K Das

Academic Editor

PLOS ONE

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