Ethnic disparities in COVID-19 mortality in Mexico: A cross-sectional study based on national data

Ismael Ibarra-Nava; Kathia G. Flores-Rodriguez; Violeta Ruiz-Herrera; Hilda C. Ochoa-Bayona; Alfonso Salinas-Zertuche; Magaly Padilla-Orozco; Raul G. Salazar-Montalvo

doi:10.1371/journal.pone.0239168

Peer Review History

Original SubmissionSeptember 18, 2020
11 Nov 2020 Decision Letter - Mary Hamer Hodges, Editor PONE-D-20-29414 Ethnic disparities in COVID-19 mortality in Mexico: a cross-sectional study based on national data PLOS ONE Dear Dr. Raul Salazar-Montalvo, 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 address each comment made by the reviewer. Please submit your revised manuscript by 10th December 2020. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. Please include the following items when submitting your revised manuscript: A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols We look forward to receiving your revised manuscript. Kind regards, Mary Hamer Hodges, MBBS MRCP DSc Academic Editor PLOS ONE Additional Editor Comments: This is a much needed paper on COVID in Mexico. However the analysis does not add a great deal to the debate but could take the analysis and discussion to a more complex level. Journal Requirements: When submitting your revision, we need you to address these additional requirements. 1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at 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. In ethics statement in the manuscript and in the online submission form, please provide additional information about the patient records used in your retrospective study. Specifically, please ensure that you have discussed whether all data were fully anonymized before you accessed them and/or whether the IRB or ethics committee waived the requirement for informed consent. If patients provided informed written consent to have data from their medical records used in research, please include this information. [Note: HTML markup is below. Please do not edit.] 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 ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: I Don't Know ****** 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 ****** 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: Yes ****** 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: This is an important and much needed paper and it really is excellent to see ethnic and gender stratification of data on COVID in Mexico. As the authors point out, COVID in Mexico is tracking the same lines as elsewhere with ethnic minority groups experiencing worse outcomes and more men dying than women. I think however that the analysis does not add a great deal to the debate and our understandings of COVID as it stands, it could however take the discussion and analysis to a more complex level. 1) Greater clarity is needed about the use of terms race, ethnicity and indigenous. Indigenous is a category defined culturally and not biologically. It is not a category of race, but of social defined characteristics such as history and language. As the authors state, in the case of these data indigeneity is defined as a speaker of indigenous language. In this case it would be good to a) state up front what the national defininition is -are the national statistics on indigeneity also based solely on lanaguage? If not, can you state what the defintion is (as opposed to the 'language' indicator in the COVID) data. 2) In relation to the above, can you clarify the relationship between ethnicity and COVID mortality. For example, is language a barrier to care, are indigenous people less likely to seek care, are there different transmission patterns in indigenous localities and what are these. 3) What about Afro-Mexican populations. Are there any data on the incidence and morbidity of COVID among other non-indigenous ethnicities? 4) Consider if you actually need to use the term 'race' and whether this just muddies the water. There are no solid data (that I am aware of) that suggest a biological risk factor for speficic racial characteristics, so race is really a proxy for social inequality. If this is the case, it should be stated and explained clearly. 5) What data are there on testing? So, for example, are indigenous people overrepresented in the mortality and hospitalisations data because they are testing less? Some context on this would help. So for example with such a high rate of uninsured indigenous people and the excessive cost of testing in the private sector, the higher death rate could be due to the lower testing rate of indigenous people. Some mention of consideration of this is important to avoid this potential confounder. 6) In relation to 5), what is known about reporting of death rates and COVID in indigenous communities? Can you say anything about the localities where indigenous patients have died? Is there likely to be underrreporting? 6) Could you include some three way tables, for example, to look at the proportion of women, men and indigenous people who receive private care? ****** 6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #1: Yes:** Jennie Gamlin [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/. 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Revision 1
11 Jan 2021 Author Response Reviewer 1 – Jennie Gamlin 1. Greater clarity is needed about the use of terms race, ethnicity and indigenous. Indigenous is a category defined culturally and not biologically. It is not a category of race, but of social defined characteristics such as history and language. As the authors state, in the case of these data, indigeneity is defined as a speaker of indigenous language. In this case it would be good to a) state up front what the national definition is -are the national statistics on indigeneity also based solely on language? If not, can you state what the definition is (as opposed to the 'language' indicator in the COVID data)? Response: Dear Ms. Gamlin. First of all, thank you for your comments and questions. They have been of great help to us. Regarding this first comment, we agree that being Indigenous is defined culturally and not biologically. For this reason, we decided to add the three definitions in our manuscript (please see page 6-7, lines 127-133). We also added a new reference to support this (see reference Our analyses only included those who spoke an Indigenous language because that was the only variable available in the data set. Fortunately, this is the definition most commonly used in Mexico. We agree that being Indigenous is not a category of race, although Indigenous people suffer from a lot of racism in Mexico. We were more careful throughout the article with the use of these two words. 2. In relation to the above, can you clarify the relationship between ethnicity and COVID mortality. For example, is language a barrier to care, are indigenous people less likely to seek care, are there different transmission patterns in indigenous localities and what are these. Response: Unfortunately, we were unable to determine if there are different transmission patterns in Indigenous localities because we had no access to this type of data. Furthermore, as far as we know, there are not available sources that report statistics specific to Indigenous communities and localities. Regarding access to care, one article did mention language barriers as a potential barrier. We added this to our discussion as we believe it is important to mention (see page 14, lines 240-243). We also discuss that only 1% of the total sample spoke an Indigenous language (compared to 6.5% of the population who report speaking an Indigenous language). This suggests an inequitable distribution of resources, testing and access to care (see page 14, lines 254-257). Thank you. 3. What about Afro-Mexican populations. Are there any data on the incidence and morbidity of COVID among other non-indigenous ethnicities? Response: Thank you for this question. We believe it is an extremely important one. Unfortunately, we do not “measure” race the same way other countries do. We discuss why in page 15, lines 260-269. To this date, no studies have been done that attempt to compare skin color and COVID-19 outcomes. 4. Consider if you actually need to use the term 'race' and whether this just muddies the water. There are no solid data (that I am aware of) that suggest a biological risk factor for specific racial characteristics, so race is really a proxy for social inequality. If this is the case, it should be stated and explained clearly. Response: Thank you for this suggestion. We chose to include the term race in our discussion because the literature uses both “race” and “ethnicity” as potential determinants of health in the COVID-19 pandemic. We understand that it is not being used in the literature to imply biological differences, but rather as a way to highlight social inequities, as you mention. In our article, we were careful with the use of the term “race”. In fact, we only mention it as a “self-identity” in the Mexican context in the discussion (see page 15, lines 262-266). 5. What data are there on testing? So, for example, are indigenous people overrepresented in the mortality and hospitalisations data because they are testing less? Some context on this would help. So, for example with such a high rate of uninsured indigenous people and the excessive cost of testing in the private sector, the higher death rate could be due to the lower testing rate of indigenous people. Some mention of consideration of this is important to avoid this potential confounder. Response: Thank you for this question. The data set we used included all the people who had been tested up until August 3rd, 2020. As mentioned in lines 254-257, Only 4178 of our sample (COVID-19 positive) spoke an Indigenous language. We checked the total sample to include those who tested negative and only 9037 spoke an Indigenous language (around 1% of all those who were tested). This is considerably lower than the 6.5% of the Mexican population who speak an Indigenous language. We mention this is a limitation in page 15, lines 254-256 as well. 6. In relation to 5), what is known about reporting of death rates and COVID in indigenous communities? Can you say anything about the localities where indigenous patients have died? Is there likely to be underrreporting? Response: Thank you. This is a great question. Unfortunately, no data on this is available in the literature or in official government sources. The data set we used includes “municipality of residence” as a variable. However, this does not mean that the person actually received attention there. The Mexican health system is using a sentinel surveillance system to diagnose COVID-19 cases, which means not every facility is actually testing suspicious patients. As mentioned above, we do believe there is underreporting because of the small proportion of Indigenous peoples being tested and diagnosed with COVID-19 (both around 1%). Attachments Attachment Submitted filename: Response to Reviewers.docx https://doi.org/10.1371/journal.pone.0239168.r002
27 Jan 2021 Decision Letter - Mary Hamer Hodges, Editor PONE-D-20-29414R1 Ethnic disparities in COVID-19 mortality in Mexico: a cross-sectional study based on national data PLOS ONE Dear Dr. %Raul G. Salazar-Montalvo%, 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 address the study limitations identifed by the reviewer ============================== Please submit your revised manuscript by %26 February%. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. Please include the following items when submitting your revised manuscript: A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols We look forward to receiving your revised manuscript. Kind regards, Mary Hamer Hodges, MBBS MRCP DSc Academic Editor PLOS ONE Additional Editor Comments (if provided): Please add in a 'limitation' section which picks up on the unanswerable questions (see original review comments as well) and considers the data in this light and comment on whether any new data has emerged since this paper was written which have any impact on the findings, since the situation is rapidly changing. [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation. Reviewer #1: (No Response) ******** 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 ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: 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 ****** 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 ****** 6. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: The authors have adequately responded to the concerns of the first review although, as they note in their response, some of the concerns cannot be addressed due to lack of data. For example the extent of underreporting is not know, the low level of testing may skew results, it is not clear where in the country data correspond to. There is further concerns that the indigenous respondents only make up 1% of the dataset, which means that they are very considerably underrrepresented in data. This being the case it would be helpful if the authors could add in a 'limitation' section which picks up on these unanswerable questions (see original review comments as well) and considers the data in this light. I also wonder if there are any new data which have emerged since this paper was written which have any impact on the findings, since the situation is rapidly changing it would be worth thinking about this. ****** 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 [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. https://doi.org/10.1371/journal.pone.0239168.r003
Revision 2
6 Feb 2021 Author Response Thank you both for your feedback and suggestions. We have made further changes to our limitations section in the Discussion. (See page 14, lines 248-252 and page 15, lines 263 and 267). Just an update regarding our testing strategy: it has not changed, unfortunately. The sentinel surveillance system is still in place, and the government has not announced any new plan regarding testing or focus on Indigenous communities. Furthermore, we thought it would be important to mention the lack of trust Indigenous communities have on the government, as this week an entire community of 40,000 Indigenous peoples are refusing to vaccinate because they do not trust the government. Attachments Attachment Submitted filename: Response to Reviewers.docx https://doi.org/10.1371/journal.pone.0239168.r004
15 Feb 2021 Decision Letter - Mary Hamer Hodges, Editor Ethnic disparities in COVID-19 mortality in Mexico: a cross-sectional study based on national data PONE-D-20-29414R2 Dear Dr. % Raul Salazar-Montalvo%, We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements. Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication. An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org. If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Mary Hamer Hodges, MBBS MRCP DSc Academic Editor PLOS ONE Additional Editor Comments (optional): Thank you for these revisions. Reviewers' comments: https://doi.org/10.1371/journal.pone.0239168.r005
Formally Accepted
23 Feb 2021 Acceptance Letter - Mary Hamer Hodges, Editor PONE-D-20-29414R2 Ethnic disparities in COVID-19 mortality in Mexico: a cross-sectional study based on national data Dear Dr. Salazar-Montalvo: I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department. If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. 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. If we can help with anything else, please email us at plosone@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr. Mary Hamer Hodges Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0239168.r006

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