PONE-D-23-30534The role of sociodemographic factors on the acceptability of digital mental health care:

A scoping review protocolPLOS ONE

Dear Dr. Lal,

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 21 2023 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,

Maher Abdelraheim Titi

Academic Editor

PLOS ONE

Journal Requirements:

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

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 

https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and 

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

2. Thank you for stating the following in the Competing Interests section: 

SL is an Associate Professor at the University of Montreal and leads a research program in the field of digital mental health. In the past 5 years SL has received research funding from the Canadian Institutes of Health Research, Canada Research Chairs program, Hoffman-La Roche, Foundation of Stars to advance this work. All of these are unrelated to this specific study. 

NA is a graduate student at the University of Montreal and is conducting this work towards partial fulfillment of requirements for a Masters of Science degree under the supervision of SL.

Please confirm that this does not alter your adherence to all PLOS ONE policies on sharing data and materials, by including the following statement: "This does not alter our adherence to  PLOS ONE policies on sharing data and materials.” (as detailed online in our guide for authors http://journals.plos.org/plosone/s/competing-interests).  If there are restrictions on sharing of data and/or materials, please state these. Please note that we cannot proceed with consideration of your article until this information has been declared. 

Please include your updated Competing Interests statement in your cover letter; we will change the online submission form on your behalf.

[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?

The research question outlined is expected to address a valid academic problem or topic and contribute to the base of knowledge in the field.

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?

The manuscript should describe the methods in sufficient detail to prevent undisclosed flexibility in the experimental procedure or analysis pipeline, including sufficient outcome-neutral conditions (e.g. necessary controls, absence of floor or ceiling effects) to test the proposed hypotheses and a statistical power analysis where applicable. As there may be aspects of the methodology and analysis which can only be refined once the work is undertaken, authors should outline potential assumptions and explicitly describe what aspects of the proposed analyses, if any, are exploratory.

Reviewer #1: Yes

Reviewer #2: Partly

Reviewer #3: Yes

**********

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

Descriptions of methods and materials in the protocol should be reported in sufficient detail for another researcher to reproduce all experiments and analyses. The protocol should describe the appropriate controls, sample size calculations, and replication needed to ensure that the data are robust and reproducible.

Reviewer #1: Yes

Reviewer #2: No

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 requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception, at the time of publication. 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

Reviewer #3: 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

Reviewer #3: Yes

**********

6. Review Comments to the Author

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.

(Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: **Summary**

This paper proposes a protocol for a scoping review that synthesizes findings across the literature related to socio-demographic variables that impact acceptability of digital mental health innovations (DMHIs).

The manuscript proposes a worthwhile review and is overall straightforward to read. I also appreciate the transparent and extensive description of the proposed search strategy! I have a number of comments regarding details that could benefit from clarification, which I have listed below.

**Comments**

1. Digital mental health innovations is abbreviated to DMHIs in the abstract but nowhere else in the paper.

2. The terms digital mental health innovations, digital mental health care and digital mental health interventions are used interchangeably. Do these refer to the same or different things?

3. Based on the introduction of the paper, it seems that the main research question is to identify what sociodemographic factors affect perceived acceptability. However, I don’t see this listed as a research question.

4. A broad definition of acceptability is included in the Introduction. Will any study considering acceptability be included, no matter how they measured/defined acceptability? For example, there are validated survey scales assessing acceptability, but acceptability can also be studied in a more qualitative way through interviews.

5. Are there any restrictions on study method or will any study considering acceptability (e.g. both quantitative and qualitative studies) be considered?

6. L50: can the authors give any examples of existing barriers to access mental health services?

7. L59-78 is a bit repetitive describing one review at a time. It may improve flow to succinctly summarize what other reviews have done, what they have not done, and how this review will bridge that gap.

8. L113: can you be more specific than ‘which digital mental health innovations’? How are you going to describe and/or categorize them? By type of platform (e.g. website, app), type of mental health symptoms it intends to address (e.g. anxiety, depression), type of population it focuses on, type of care it offers, etc.

9. Can the authors clarify the inclusion criterion that 90% or more of the study sample needs to represent a specific sociodemographic group? If 60% of study participants identify as men, but the study showed that male participants rated digital mental health interventions significantly higher on acceptability than other gender identities, would this study not be relevant to the review?

10. It would help with readability to include an overview of all inclusion and exclusion criteria in a bullet-point list or table.

11. L215-216: how will the grey literature be used? Will theses and dissertations be included in the review as articles, or will the reference lists of theses be used to identify other peer-reviewed studies?

12. L329: how are absolute findings evaluated? E.g. for the example that is given, ‘men demonstrated a high level of perceived acceptability’ => this may vary across the articles you are including in your review, but how is ‘high’ determined? Are there validated cut-off scores that determine whether something has a high score of acceptability? This goes back to my earlier comment whether only a quantitative measure of acceptability will be considered or if other assessments of acceptability will be included in the review as well.

13. L343: it is mentioned that the review will not evaluate the methodological rigor of the included studies. However, will some kind of other, less rigorous, quality assessment be carried out to screen articles?

Reviewer #2: General comments

=============

I read with interest your scoping review protocol on the role of sociodemographic factors on the acceptability of digital mental health care. This review will add an important contribution to the eMental health field. Below are some suggestions to improve the clarity, and add to the quality, of this proposal. I wish you all the best with your work!

Major inquiries

=============

1. It is unclear to me how research question 1 (page 5, line 113) directly addresses your objective on what is the role of sociodemographics in the degree of perceived acceptability of DMHI (lines 107-108). Can you please clarify?

Of note, while you should describe the sample of studies of DMHI included in the review, that does not mean this summary should form a research question. (Also, if you answer question 3, you will be indicating which interventions have been evaluated through a sociodemographic lens.)

2. Research question 3 (page 6, lines 117-118) does not include the neutral category that you outline in the Data Synthesis section (page 15, line 326). If your objective is focused on the degree of perceived acceptability, it seems that ‘neutral’ would be important to acknowledge as part of the spectrum?

3. Determining study inclusion necessitates a detailed evaluation—1) determining the report of relative or absolute acceptability, and if absolute acceptability is reported, the need to determine if at least 90% of the sample represents a specific sociodemographic group; and 2) determining if acceptability is assessed independently in the case of blended interventions. Given these requirements for inclusion, it is important to include details on the screening strategy (tasks/steps; page 12) and any instructions/parameters for determining these criteria (e.g., Which values are used for calculating the proportion of the study sample? How to determine an independent acceptability assessment – Can multivariable modelling results be used? Does the acceptability finding need to be reported on its own?). The inclusion of these details will further operationalize the review and promote transparency and replicability.

4. Page 15, line 332: It is stated that additional findings may be reported based on the identification of patterns. What analytic approach will be used to identify patterns?

5. Page 15, line 334: You note that it may be necessary to use visual representation if the findings are complex. Can you describe more details regarding ‘complexity’ to promote transparency and replicability? In particular, how are you defining complexity, and what is the process that will be used to determine complexity?

6. I am curious to know more about your approach to defining high acceptability (report in a study of a positive association) (page 15, line 326). Typically, general interpretation of measures of association follows this guide: weak (0.01-0.09), moderate (0.10-0.29), strong (0.30-0.59), very strong (0.60-0.99). Based on your definition, in your review, it reads that you will report a weak, positive association as reflecting high acceptability. Can you share your thoughts on whether or not you think your interpretation of any positive association as ‘high acceptability’ could be misleading, and why/why not?

7. In its present state, the conclusion serves as a detailed account of the strengths and limitations of the review. These should be stated in its own section. The conclusion should serve as a brief summary. Revisions are necessary.

Minor inquiries and comments

=============

1. I understand that you are interested in synthesizing studies of associations between sociodemographics and perceived acceptability. As this is a scoping review, would you consider adding another objective to slightly broaden the focus? In addition to reviewing studies that examined associations, would you also consider reviewing all studies that included examining perceived acceptability of a DMHI. I believe these studies would be included in the search strategy. For this group of studies, you could review the participant characteristics across studies to explore the diversity from which acceptability findings are based on. While this addition broadens the review, it would add value as you could comment on the diversity of study samples and what is needed moving forward in terms of EDI in the DMHI research field.

2. In the introduction, the second paragraph is repetitive in structure: sentence introducing a prior review followed by a sentence starting with ‘however’. This paragraph requires revision to improve reader engagement.

3. On page 5 in the statement of the primary objective, you can remove the examples in brackets “(e.g., age, ethnicity, gender)”. Objectives do not need parenthesized examples as operational details should be described in the methods. This is what you have done on the following page under Population.

4. Page 10, line 213: “Only materials published between January 2013 and June 2023 will be considered.” This is already stated on the previous page (page 9; line 199). Similarly, the content on page 10, line 214 is also duplicative “Moreover, the reference list of secondary sources, identified as relevant to the topic of inquiry, will be examined.” See page 9, lines 202 and 203.

5. Page 14, line 303 should be “As data are extracted” (plural); line 315 should be “The extracted data will be” as extraction is a descriptive word in this sentence.

6. Page 14, line 315. I suggest integrating this sentence where it is relevant as it is not a stand-alone paragraph. (I suspect you can move it to the paragraph starting on line 324, re: summary of the key findings on the role of sociodemographics?)

Reviewer #3: An appropriate and timely protocol proposing to synthesise data on the experience, specifically the acceptability, of taking part in digital health interventions, amongst persons who have taken part in such interventions focused on mental health outcomes. Acceptability as a concept is clearly operationalised. The literature search and analysis approach seem appropriate and the inclusion and focus on demographic sub-group analysis is very important and will ensure the results are meaningful and again there are clear criteria for inclusion or exclusion of studies based on the way the demographic data are presented. Overall, this is a well-written and competently described review protocol. One minor comment - the focus in the opening line on Canada is not necessary or appropriate for an international journal.

**********

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: Judith Borghouts

Reviewer #2: No

Reviewer #3: Yes: Prof. Brian McGuire

**********

[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-23-30534R1The role of sociodemographic factors on the acceptability of digital mental health care:

A scoping review protocolPLOS ONE

Dear Dr. Lal,

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 Apr 01 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,

Maher Abdelraheim Titi

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.]

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?

The research question outlined is expected to address a valid academic problem or topic and contribute to the base of knowledge in the field.

Reviewer #1: Yes

Reviewer #4: 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?

The manuscript should describe the methods in sufficient detail to prevent undisclosed flexibility in the experimental procedure or analysis pipeline, including sufficient outcome-neutral conditions (e.g. necessary controls, absence of floor or ceiling effects) to test the proposed hypotheses and a statistical power analysis where applicable. As there may be aspects of the methodology and analysis which can only be refined once the work is undertaken, authors should outline potential assumptions and explicitly describe what aspects of the proposed analyses, if any, are exploratory.

Reviewer #1: Yes

Reviewer #4: Yes

**********

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

Descriptions of methods and materials in the protocol should be reported in sufficient detail for another researcher to reproduce all experiments and analyses. The protocol should describe the appropriate controls, sample size calculations, and replication needed to ensure that the data are robust and reproducible.

Reviewer #1: Yes

Reviewer #4: 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 requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception, at the time of publication. 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 #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 #1: Yes

Reviewer #4: Yes

**********

6. Review Comments to the Author

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.

(Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: I thank the authors for their responses to our comments and revision of the paper.

I believe the authors’ efforts to address our comments greatly improve the protocol, and I am happy with the changes made.

Reviewer #4: Thank you for the opportunity to review this paper as a third reviewer. I have seen the previous versions and comments from reviewers 1 and 2 and am glad the issues have been addressed.

I have one suggestion related to the concept of 'acceptability', which is well defined in the paper, but less so in the search strategy which was included as an appendix. The terms 'patient preference', 'consumer satisfaction' and 'patient satisfaction' have not been included, and it seems these very similar - yet admittedly different - concepts may also yield important results. I'm wondering if including these terms in the first lines of the search along with the acceptability terms (lines 1-4) would be useful. If in testing these terms, they are not of use, perhaps a short explanation could be added? I am not confident that other authors will have as well defined a concept of acceptability and will be using other definitions.

**********

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: Judith Borghouts

Reviewer #4: Yes: Amanda Ross-White

**********

[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.

The role of sociodemographic factors on the acceptability of digital mental health care:

A scoping review protocol

PONE-D-23-30534R2

Dear Dr. Lal,

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 will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, 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,

Maher Abdelraheim Titi

Academic Editor

PLOS ONE

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?

The research question outlined is expected to address a valid academic problem or topic and contribute to the base of knowledge in the field.

Reviewer #4: 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?

The manuscript should describe the methods in sufficient detail to prevent undisclosed flexibility in the experimental procedure or analysis pipeline, including sufficient outcome-neutral conditions (e.g. necessary controls, absence of floor or ceiling effects) to test the proposed hypotheses and a statistical power analysis where applicable. As there may be aspects of the methodology and analysis which can only be refined once the work is undertaken, authors should outline potential assumptions and explicitly describe what aspects of the proposed analyses, if any, are exploratory.

Reviewer #4: Yes

**********

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

Descriptions of methods and materials in the protocol should be reported in sufficient detail for another researcher to reproduce all experiments and analyses. The protocol should describe the appropriate controls, sample size calculations, and replication needed to ensure that the data are robust and reproducible.

Reviewer #4: 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 requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception, at the time of publication. 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 #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 #4: Yes

**********

6. Review Comments to the Author

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.

(Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #4: You have adequately explained the search rationale and addressed the limitations. Thank you for this revision.

**********

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 #4: Yes: Amanda Ross-White

**********