Dear Dr. Rahman,

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We look forward to receiving your revised manuscript.

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Jiawen Deng

Academic Editor

PLOS ONE

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Natural Earth (public domain): We%20note%20that%20Figure%201%20in%20your%20submission%20contain%20%5bmap/satellite%5d%20images%20which%20may%20be%20copyrighted.%20All%20PLOS%20content%20is%20published%20under%20the%20Creative%20Commons%20Attribution%20License%20(CC%20BY%204.0),%20which%20means%20that%20the%20manuscript,%20images,%20and%20Supporting%20Information%20files%20will%20be%20freely%20available%20online,%20and%20any%20third%20party%20is%20permitted%20to%20access,%20download,%20copy,%20distribute,%20and%20use%20these%20materials%20in%20any%20way,%20even%20commercially,%20with%20proper%20attribution.%20For%20these%20reasons,%20we%20cannot%20publish%20previously%20copyrighted%20maps%20or%20satellite%20images%20created%20using%20proprietary%20data,%20such%20as%20Google%20software%20(Google%20Maps,%20Street%20View,%20and%20Earth).%20For%20more%20information,%20see%20our%20copyright%20guidelines:%20 http:/journals.plos.org/plosone/s/licenses-and-copyright.%0b%0bWe%20require%20you%20to%20either%20(1)%20present%20written%20permission%20from%20the%20copyright%20holder%20to%20publish%20these%20figures%20specifically%20under%20the%20CC%20BY%204.0%20license,%20or%20(2)%20remove%20the%20figures%20from%20your%20submission:%0b%0ba.%20You%20may%20seek%20permission%20from%20the%20original%20copyright%20holder%20of%20Figure%201%20to%20publish%20the%20content%20specifically%20under%20the%20CC%20BY%204.0%20license.%20%0b%0bWe%20recommend%20that%20you%20contact%20the%20original%20copyright%20holder%20with%20the%20Content%20Permission%20Form%20(http:/journals.plos.org/plosone/s/file?id=7c09/content-permission-form.pdf)%20and%20the%20following%20text:%0b“I%20request%20permission%20for%20the%20open-access%20journal%20PLOS%20ONE%20to%20publish%20XXX%20under%20the%20Creative%20Commons%20Attribution%20License%20(CCAL)%20CC%20BY%204.0%20(http://creativecommons.org/licenses/by/4.0/).%20Please%20be%20aware%20that%20this%20license%20allows%20unrestricted%20use%20and%20distribution,%20even%20commercially,%20by%20third%20parties.%20Please%20reply%20and%20provide%20explicit%20written%20permission%20to%20publish%20XXX%20under%20a%20CC%20BY%20license%20and%20complete%20the%20attached%20form.”%0b%0bPlease%20upload%20the%20completed%20Content%20Permission%20Form%20or%20other%20proof%20of%20granted%20permissions%20as%20an%20%22Other%22%20file%20with%20your%20submission.%0b%0bIn%20the%20figure%20caption%20of%20the%20copyrighted%20figure,%20please%20include%20the%20following%20text:%20“Reprinted%20from%20%5bref%5d%20under%20a%20CC%20BY%20license,%20with%20permission%20from%20%5bname%20of%20publisher%5d,%20original%20copyright%20%5boriginal%20copyright%20year%5d.”%0b%0bb.%20If%20you%20are%20unable%20to%20obtain%20permiss http://creativecommons.org/licenses/by/4.0/).%20Please%20be%20aware%20that%20this%20license%20allows%20unrestricted%20use%20and%20distribution,%20even%20commercially,%20by%20third%20parties.%20Please%20reply%20and%20provide%20explicit%20written%20permission%20to%20publish%20XXX%20under%20a%20CC%20BY%20license%20and%20complete%20the%20attached%20form.”%0b%0bPlease%20upload%20the%20completed%20Content%20Permission%20Form%20or%20other%20proof%20of%20granted%20permissions%20as%20an%20%22Other%22%20file%20with%20your%20submission.%0b%0bIn%20the%20figure%20caption%20of%20the%20copyrighted%20figure,%20please%20include%20the%20following%20text:%20“Reprinted%20from%20%5bref%5d%20under%20a%20CC%20BY%20license,%20with%20permission%20from%20%5bname%20of%20publisher%5d,%20original%20copyright%20%5boriginal%20copyright%20year%5d.”%0b%0bb.%20If%20you%20are%20unable%20to%20obtain%20permiss" http://www.naturalearthdata.com/

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Additional Editor Comments :

1. Authors' claims to be the first comprehensive synthesis are inaccurate. In fact, the authors cited several studies themselves that already pooled prevalences and risk factors across South Asian nations. Please justify the novelty and necessity of the proposed review.

2. The term "associated factors" is ill-defined. Please discuss how these factors will be categorized or specifically which factors will be assessed. Systematic reviews need to have a concrete research question; "associated factors" is too vague.

3. How exactly will the NOS be modified? Why are only medium and good quality studies included? RoB ratings can be subjective and there is a risk of leaving out relevant studies. Usually low risk studies are examined via sensitivity/subgroup analyses by RoB and rarely are they explicitly excluded.

4. How will the effects of "associated factors" be assessed? Will there be any pooling or quantitative synthesis? If so, will these be assessed as odds ratios, meta-regressions, or something else?

5. Please name specific grey literature sources that will be searched.

6. In general, there is language issues. There are long rambling sentences which are hard to read.

7. Please review your introduction and discussions, and make sure that your statements regarding mental health stigma and systemic challenges are backed by academic citations.

8. Certain parts of the manuscript seems to have been copy pasted, ?from somewhere else. The part on heterogeneity is mentioned twice in the manuscript, for instance.

9. Will any transformation be applied to the prevalence values prior to pooling? Please clarify statistical plan.

10. There is no GRADE framework available for prevalence meta-analyses. Please remove this.

11. Please remove all figures. You do not need placeholder figures nor do you need a figure for your introduction. The last figure (network plot) seems to be for illustrative purposes only and serve no real purpose.

12. You mention time cutoff for included articles being March 2025 in one section of the manuscript but May 2025 in other sections. Please explain this discrepancy.

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

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

Reviewer #1: Yes

Reviewer #2: Partly

Reviewer #3: Yes

**********

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

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

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

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

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

The PLOS Data policy

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

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

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

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

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

Reviewer #1: Understanding the prevalence of depression and associated risk factors is essential to guide targeted interventions and evidence-based policy reforms that support the mental well-being of future healthcare professionals. By systematically synthesizing data from observational studies, this review will provide a comprehensive synthesis of depression prevalence and its correlates among medical students in the South Asian region, laying the groundwork for preventive strategies and improved mental health

care practices.

Reviewer #2: I would like to express my sincere appreciation for the opportunity to review this valuable and comprehensive work. The manuscript presents an insightful and systematic meta-analysis study protocol for depression among medical students in South Asia, with a strong methodological framework and a high quality of included studies.

I have some minor questions and requests:

1. The objective is clearly defined, and the author used PICO (Population, Intervention, Comparator, Outcome).

2. As a depression case, what are the standard criteria used among different studies to give a standard diagnosis of depression among medical students in the South Asian region? Should be stated.

3. The author didn’t define depression cases in different studies.

4. Regarding I² categorized as low (≤25%), moderate (50%), or high (≥75%), what about the range from 25% to 50%?

5. For depression measuring tools, what is the difference between self-reported and patient-reported?

6. Although the topic is clinically or scientifically significant, any justification for conducting this study since many other similar meta-analyses were conducted globally?

7. The study's rationale didn’t justify the need for a new review…

8. Inclusion and exclusion criteria are clearly specified.

9. The author should elaborate more in the discussion.

Reviewer #3: This protocol presents a timely and well-structured plan for a systematic review and meta-analysis addressing the prevalence and associated factors of depression among medical students in South Asia. The rationale is strong and grounded in regional disparities in mental health research, with a clear and relevant research question formulated using the PICO framework.

The proposed methodology is rigorous, employing best practices such as PRISMA, MOOSE, and NOS guidelines, and registration in PROSPERO. The inclusion of subgroup analysis and sensitivity testing further adds to the protocol’s analytical strength.

Strengths:

Comprehensive search strategy, including grey literature and citation chaining.

Transparent risk of bias assessment and use of validated scales (e.g., PHQ-9, BDI).

Use of standard software (R, meta package) and appropriate statistical models.

Clear data availability and ethics statements.

Areas for Minor Revision:

1. Timeline Clarification: The projected timeline (completion in mid-2026) seems extended relative to typical protocol expectations. Consider justifying or adjusting this to reflect a more standard 12–18 month execution window.

2. Subgroup Exclusions: Excluding medical students with comorbid physical health conditions may omit relevant populations. Please clarify the rationale or consider including such data with subgroup analysis.

3. Typographical Edits: Minor inconsistencies in English usage (e.g., “analysed” vs. “analyzed”) and repeated use of placeholders like “XXXX” in figures. A proofreading pass is recommended to ensure consistency and polish.

Overall, the protocol is well-prepared and likely to yield meaningful and actionable insights for medical educators, policymakers, and researchers across South Asia. I recommend acceptance following minor revisions.

**********

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:  Assoc. Prof. Dr. Hassanain Al-Talib

Reviewer #3: 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. Rahman,

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.

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,

Jiawen Deng

Academic Editor

PLOS ONE

Journal Requirements:

If the reviewer comments include a recommendation to cite specific previously published works, please review and evaluate these publications to determine whether they are relevant and should be cited. There is no requirement to cite these works unless the editor has indicated otherwise. 

Additional Editor Comments:

1. It is probably inappropriate to say that the review itself will follow PRISMA-P. The review itself should follow PRISMA, but the protocol should be reported following PRISMA-P.

2. At this stage I would like for the authors to lock in their information sources. Instead of saying "from a wide range of reputable sources, INCLUDING..." Simply list all databases that will be used.

3. The condition section is still not clear. Again, please list all standardized and validated tools that you are seeking in the included studies. Please also include threshold values as these tools are validated at a certain threshold level.

For associated factors, please provide the full list instead of giving examples of each category. The review methodology must be concrete in this regard.

4. Please explain the difference between MBBS and undergraduate medical students.

5. Please avoid the term "depression" in your protocol, as validated scales (such as PHQ-9) only screens for depressive SYMPTOMS, and they do not provide a formal diagnosis of depression.

6. Please provide the full list of demographic information being extracted.

7. Authors mentioned "The main focus will be on extracting...any reported levels of depression severity (e.g., mild, moderate, severe) based on DSM-IV criteria." Please confirm that you are aiming to extract severity based on DSM instead of different threshold levels in the validated tools. It is unclear how severity can be extracted based on DSM.

8. What kind of modification is being done to NOS? Also note that different versions of the NOS exists for different study types; please specify which one will be used.

9. There is still a redundant section on "Strategy for data synthesis", which curiously contains a copy-pasted version of the database search methodology.

Please very carefully review your manuscript to ensure that these types of errors are not included.

10. Please remove the section on status and timeline of the study. This is not typically included in systematic review protocols.

11. The incorrect checklist is attached. You should attach the PRISMA-P checklist, not the PRISMA checklist (this one is reserved for your final review).

12. Please review whether your figures are necessary. Figures 1 and 2 are not needed as they contain no data. Likewise, Figure 3 does not contain any information and it is unclear what the graph represents or what readers are supposed to draw from it. Figure 4 contains a summary of data from other studies and this is not typically seen in protocol publications.

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

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

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

Reviewer #1: Yes

**********

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

Reviewer #1: Yes

**********

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

Reviewer #1: Yes

**********

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

The PLOS Data policy

Reviewer #1: Yes

**********

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

Reviewer #1: Yes

**********

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

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

Reviewer #1: I am satisfied by the revisions made to the paper.

I am satisfied by the revisions made to the paper.

**********

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.

A Systematic Review and Meta-analysis Protocol on Depressive Symptoms Among Medical Students in South Asia Using Patient-reported Validated Assessment Tools: Prevalence and Associated Factors

PONE-D-25-27075R2

Dear Dr. Rahman,

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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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,

Jiawen Deng

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments: