PONE-D-21-07087

ICMR Task Force Project- Survey of the incidence, mortality, morbidity and socio-economic burden of snakebite in India: A study protocol

PLOS ONE

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Academic Editor

PLOS ONE

Additional Editor Comments:

1. The manuscript is not written as a study protocol but reads like an internal/study document. Other reviewers have also referred to this issue with the writing style. Please update.

2. Introduction, second last paragraph - The premise of undertaking the study is mentioned as the need to “understand the socioeconomic impact and to regulate control of anti-venoms and their distribution policies.” The evidence so far from India suggests that anti-venom is not used in many cases, its availability is a concern in rural areas, and not all victims are taken to a medical doctor. More in-depth exploration is needed for understanding the issues with anti-venom use, but that is not covered or addressed in this protocol.

It appears that the investigators have assumed that most victims are taken to hospital, as reflected in Annexure 2 (proforma) – question 17. If the victim was not taken to a hospital, then it appears no further information on injury/treatment is collected.

3. Introduction, last paragraph – There are reasonable data available to suggest that snakebite mortality is a public health concern, and undertaking a study for incidence and mortality seems not fully justified. Much less data are available on the pattern of injuries and cost of illness among snakebite victims, however, the study proforma does not show that it will be captured well for meaningful interpretation. Annexure 3 does not capture much on injury pattern and assumes that injury will be seen in all victims, and that the respondents will be able to inform injury details. Furthermore, the economic detail section also assumes that all victims will be income-earners and does not differentiate between a fatal and non-fatal case. The investigators could refer to injury-related economic loss/details guidelines to capture relevant information.

4. Secondary outcomes (page 12) - Annexure 3 does not capture much information on management pattern for venomous snakebites that can help strengthen the national protocol. It also does not capture information on medical attention seeking behaviour pattern among the snakebite victims beyond hospitals.

5. Methodology, data collection (pages 14-16)

a. How will snakebite cases be identified by the field workers? Will this be based on hear-say from the local people or victim’s family? There is enough evidence to suggest that a snake is not seen in all cases of snakebites. How will then confirmation be made of a case being that of a snakebite for inclusion in the study? This is of utmost importance in case of death.

b. It is stated that the field worker will collect the data from “the victim within 2 weeks of discharge from hospital or from close relatives in case of death”. Again, the investigators seem to assume that all victims also access hospital, which is not the case.

c. Why will ASHA be given incentive for reporting incidence or death due to snakebites in that area, when she is being informed of this by field workers?

d. Who are these field workers? Will they be recruited specifically for this study? What training will they be provided with for completing the tool?

e. Will the Annexures be translated into local languages? Please provide the details of the process.

6. Methodology, data entry (pages 16) - It is stated that the “data gathered at the Panchayat (village) level would be collated on the Questionnaire sheet in the regional language by the field officers, gathered data is then entered on the Tab PC by the District coordinator in English”.

Are these village level data in addition to Annexure 2? Please clarify. Also, please indicate what will be captured in regional language as Annexure 2 seems to be yes/no type of tool.

7. Study challenges (page 18) – Please provide evidence to justify that there will be recall bias in case of snakebite.

8. Annexure 1, the Participant information sheet and Informed Consent

a. The form does not state which organisation is undertaking the research study/data collection. Only names of PI are written with no institutional affiliation.

b. This statement in background is incorrect - “There is no real epidemiological data on the prevalence, incidence and morbidity resulting from snakebite in India”. Please update to reflect the current scenario or simply mention that more specific data are needed.

c. The form will be used for family of the deceased and also for victim who survived. It does not seem to indicate empathy/sympathy for the loss of a family member.

d. The form does not mention the study area, and how the ASHA was able to get the information on snakebite to contact the household for interview.

e. The form does not specify what type of data will be collected from the participants for them to make an informed choice to participate.

f. Informed consent shows space for signature of the Principal Investigator. It is unlikely for him/her to be available at the time of interview.

g. Such forms typically have footer or header to indicate the number of pages for the participant to be aware that nothing is missed/not shown before he/she decides to sign. This is not seen in the annexure provided.

9. Annexure showing the budget is not needed. Please remove.

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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?

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: No

Reviewer #2: Yes

Reviewer #3: Yes

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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: No

Reviewer #2: No

Reviewer #3: Partly

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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: No

Reviewer #2: No

Reviewer #3: No

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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: No

Reviewer #2: No

Reviewer #3: No

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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

Reviewer #3: Yes

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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: Unfortunately, I have to recommend to reject the manuscript. The current document is a study protocol to be used to inform study personnel and to plan the study. It provides general information, which are unspecific and in part redundant (some sentences are even included twice ...). It is not clear who is the target audience of this document, since it does not provide new information relevant to anyone outside the study team.

However, I would like to motivate you to complete the study and to publish the findings as they will be very relevant for the management of snakebites in India. The submitted document can be used to draft parts of the method section.

Reviewer #2: ICMR Task Force Project- Survey of the incidence, mortality, morbidity and socioeconomic

burden of snakebite in India: A study protocol

Major comments

• Sri Lankan study is a community-based study where the study was planned to physically visit and obtained snakebite data from 1% of households in Sri Lanka

• Authors claim this study will cover 6.12% and compared with the above Sri Lankan study. However, this cannot be compared as the proposed study is not a community-based survey with physically visiting houses.

• This study will not be able to accurately estimate the estimate the incidence, mortality, morbidity and socioeconomic burden of snakebite as the snakebite reporting mechanism can easily under report snakebites as the study entirely depend on the reporting of field officer (i.e. not all snakebites will be captures as this is not a community based survey).

• Not clear how the management data (eg. Number of ASV vials) can be obtained without reviewing hospital records as the questionnaire will be filled at households.

• Further, Districts, Taluks, ect are not randomly selected, hence results cannot be generalized to the country.

Minor comments

• Typos and formatting errors in the proposal.

• Some abbreviations are expanded – Eg. ASHA, AIMS

Reviewer #3: This proposal presents a protocol followed in a comprehensive community-based epidemiological assessment of snakebite in 31 districts in India. To achieve the challenge of detailing epidemiological aspects in one of the most densely populated areas affected by snakebite, the authors require a protocol that allows collecting information on a large scale and a good data curation (and conformation) system. Thus, presenting a well-detailed protocol for a community-based study of this nature constitutes an exciting contribution that can help reproduce similar efforts in other settings. As such, it seems to me that the authors should be motivated to disclose it. However, before this is published in PLOs One, I think the authors should address some of the observations below.

Introduction. This section is somewhat long and could be shortened a bit, especially if we consider that the situation of snakebite in India has been previously reported. The authors should recognize that other efforts at the regional and local levels have been carried out in the subcontinent. Thanks to these studies, we have a basis for the complicated situation in India. The justification for this new examination should concentrate on the thoroughness of the population/region covered.

The introduction needs to address a core aspect of the protocol: the organization of health services in the study region. In particular, the definition and role of ASHAs (Accredited Social Health Activists) in health care. These community activists are a peculiarity of the Indian system and vital to collecting epidemiological information in this protocol. Therefore, the mechanisms they use to detect health issues in their communities should be better explained.

Goals. The objectives are reasonable. Those related to the estimation of incidence and mortality and the type of medical care (traditional or modern) followed by those affected can be directly derived from the interviews. Other objectives, such as documenting clinical information (predominant symptoms, duration of hospital stay, vials of ASV, complications etc) will require verification since the patient or her family members are not always aware of the procedures or pathologies suffered. The proposed methodology does not clarify whether this information will come directly from the medical centers or if it will only depend on the people interviewed in the community. If the latter, what would be the mechanisms for confirming the accuracy of that information?

In the Study design section, mention is made of the four most important species from the medical point of view of India (the big four) and other species that, due to the location of the study, could cause some of the recorded accidents. However, the text is long and does not provide more information on the study's design, so I suggest that it be omitted.

Outcomes. A series of possible primary products of this intervention are indicated: on the one hand, epidemiological information on the incidence of snakebite at the geographical level and the estimation of mortality and economic burden. As secondary outcomes, aspects of the poisoning and its treatment are indicated. As mentioned above, it is impossible to determine the origin of the information on clinical characteristics of the treatment in this protocol, which leaves us without knowing how some of these intended outcomes can be achieved. This section is also repetitive.

The proposed methodology states that the survey will be carried out in a region comprising 31 districts, with close to 84 million inhabitants (about 17 million households). Indeed conducting a study of such magnitude at the community level will require an army of participants, including interviewers and organizers. Field workers will conduct interviews, an unspoken number of them every 10-15 blocks. If 336 blocks are expected to be evaluated, then the minimum number of interviewers would be 22, but the actual number is unknown.

The Data Collection, quality checks, and monitoring section represent the core aspects of the protocol. However, some details should be clarified as well. It is indicated that these workers would attend the calls of the ASHAs, who would report the cases directly from the community. As mentioned before, further clarification is required about this alert system and the role that ASHAs play in public health, and the mechanisms of their participation. One aspect mentioned is that ASHAs will receive incentives to report information on snakebite incidence or death. This could incentivize false reports. What control do you have for it?

The field-worker will collect the data on the bite and the treatment. In our own experience, relying on medical information supplied by patients can lead to inaccurate records that lead to erroneous conclusions. How will the authors ensure the quality of the information provided? Although the questionnaires are reviewed to ensure they are complete, there is no indication on how to endorse the quality of the information provided. This aspect is key to distinguish perception studies from those that try to reflect the reality of a situation.

Finally, several of the acronyms used in this section are not explained, which makes revision difficult.

Analytical aspects. Although some of the variables to be evaluated are mentioned, only general references are made to the analytical procedures ("Data collected in the questionnaire will be analyzed using appropriate statistical techniques."), So this component cannot be properly evaluated.

The economic and social burdens will be evaluated from the information provided by the patients, but again there is no indication of verification of the information provided.

In summary, epidemiological studies based on community-level assessments are an essential alternative to collect valuable information on snakebite in situations where an adequate hospital registration system is not available or where the population does not always use the health system to be cared for. The proposal of the study proposed by Menon et al can constitute a very important contribution in this field. However, the submitted manuscript must be trimmed in some repetitive aspects and better detailed in core aspects of data collection and curation. One suggestion to attach the questionnaire presented to participants.

I want to end with a note instead addressed to the editor. As there are no numbered lines in the text, it isn't easy to refer to observations and support suggestions. The magazine's editorial board should consider the numbering of lines as a requirement when submitting the article.

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Reviewer #1: No

Reviewer #2: No

Reviewer #3: No

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PONE-D-21-07087R1ICMR Task Force Project- Survey of the incidence, mortality, morbidity and socio-economic burden of snakebite in India: A study protocolPLOS ONE

Dear Dr. MENON,

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 May 09 2022 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Benito Soto-Blanco, DVM, MSc, PhD

Academic Editor

PLOS ONE

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

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. 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 #3: Yes

Reviewer #4: Yes

Reviewer #5: Yes

Reviewer #6: Yes

Reviewer #7: Yes

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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 #3: Yes

Reviewer #4: Partly

Reviewer #5: Yes

Reviewer #6: Partly

Reviewer #7: Partly

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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 #3: Yes

Reviewer #4: No

Reviewer #5: Yes

Reviewer #6: No

Reviewer #7: Yes

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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 #3: Yes

Reviewer #4: Yes

Reviewer #5: Yes

Reviewer #6: No

Reviewer #7: Yes

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

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #3: Yes

Reviewer #4: Yes

Reviewer #5: Yes

Reviewer #6: Yes

Reviewer #7: Yes

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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 #3: This new version of the protocol is more precise and concise, showing the procedure for a massive effort to gather information on the snakebite in India from the perception of those affected. I believe that the modifications made by the authors in this new version are adequate, and the protocol can be published.

Reviewer #4: Thank you very much for inviting me to review this important study protocol to study the incidence, mortality, morbidity and socio-economic burden of snakebite in India. Overall I would like to congratulate the authors on developing a comprehensive protocol. However, there are few major concerns, especially with regard to the sampling strategy and data collection, which need to be addressed by the authors for the data collected to be accurate and reflective of the actual burden of snakebites in the population studied.

Study aims

Should be corrected as ‘Our study aims to estimate the epidemiological and socio-economic effects due to snakebite in India’

Study design

The authors need to give more details of the sampling strategy including how the individual blocks are selected within each districts, how many wards are roughly included in a block etc. It would be clearer if the authors could use a flow diagram to show the sampling strategy.

Data collection

There major concerns with regard to the adequacy and accuracy of the data collection.

1. The authors state that the ASHAs will cover each ward that will include 1000 population. Is there a possibility that ASHAs may miss some of the snakebites that occur? If so what are the measures the investigators have taken to minimize missed reporting? Have they thought of carrying out public awareness campaigns about informing about the snakebites to their ASHAs before the study is started?

2. The authors need to provide more information on the gathering of information and filling the questionnaires by the field workers. It appears that most of the information will be obtained through hospital discharge notes. What happens if there are no or incomplete discharge summaries? How are the investigators going to obtain information about individuals who have sought native/ local treatment where there will be no treatment records?

3. One of the main concerns of the study protocol is the accurate identification of the snake species. They need to provide more details on how this will be done. Are they going to rely on hospital records for this? Are they going to limit species identification to cases where the dead or the live snake was brought to the hospital? Will they include species identified based on the description of the snake?

Reviewer #5: Good study proposal on an epidemiological topic that appears to have a dearth of current literature. Challenges that likely will arise include lack of confirmation of snake, recall bias, dry bites, etc. Would recommend keeping working data evaluating whether the snake was visualized, how the confirmation took place (photo, visual, combined with consistent clinical findings) to get a better sense of distribution. This could also help inform the geographic distribution patterns of specific species in different areas. This project will be a big undertaking, however is worthwhile and ambitious. Determining socioeconomic burden may prove challenging also as metrics will need to be normalized across various income levels, etc. May be worthwhile tabulating total costs of treatment as an objective figure to get a sense of the baseline findings. Are the median income levels and socioeconomic determinants of each geographical area/district being considered? Overall, this is an interesting study and I look forward to the findings.

Reviewer #6: 

- important study but I had a few comments/concerns:

- the study design - is it prospective, a survey, or retrospective? It is said to be prospective, but recall bias is mentioned which would be an issue for a retrospective design?

- there is use of “his” in referring to investigators but “her” when referring to the site workers (ASHWs) - this needs to be changed to gender neutral language (eg their)

- acronyms need to be spelt out in full at first time of use - eg ASHW, NCD

- in abstract the word “ward” is used, but this is an ambiguous term - in some countries a “ward” in an inpatient unit, and so I originally interpreted this as inpatient recruitment only, and hence big flaws in capturing true incidence. Later on in paper it is defined as a small community village unit. Suggest abstract word is changed to a non-ambiguous term

- towards the end section there is use of the term “down trodden” poor people - I think socioeconomically disadvantaged probably a better/preferred term.

Thanks for invitation.

Reviewer #7: The authors present interesting data on a largely neglected area of research, i.e. envenoming epidemiology. The scarcity of data in this field necessitates that any data that can be published, should be published and, thus, I believe this study merits publication. However, there remain some major revisions to ensure the coherency and soundness of the presented data.

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Reviewer #3: Yes: Mahmood Sasa Marin

Reviewer #4: Yes: Eranga Sanjeewa Wijewickrama

Reviewer #5: No

Reviewer #6: No

Reviewer #7: No

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ICMR Task Force Project- Survey of the incidence, mortality, morbidity and socio-economic burden of snakebite in India: A study protocol

PONE-D-21-07087R2

Dear Dr. MENON,

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,

Benito Soto-Blanco, DVM, MSc, PhD

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

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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

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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

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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

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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

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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: Thank you very much for letting me review the revised version of this study protocol. The authors have adequately addressed the concerns raised during the review. I recommend publication of this study protocol in PLOS One.

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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 #4: Yes: Eranga Sanjeewa Wijewickrama

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