Unexplained mechanism of subdural hematoma with convulsion suggests nonaccidental head trauma: A multicenter, retrospective study by the Japanese Head injury of Infants and Toddlers study (J-HITs) group

Ayumi Narisawa; Masahiro Nonaka; Nobuyuki Akutsu; Mihoko Kato; Atsuko Harada; Young-Soo Park

doi:10.1371/journal.pone.0277103

Peer Review History

Original SubmissionMay 17, 2022
9 Aug 2022 Decision Letter - Kenta Matsumura, Editor PONE-D-22-14343Unexplained mechanism of subdural hematoma with convulsion suggests nonaccidental head trauma: A multicenter, retrospective study by the Japanese Head injury of Infants and Toddlers study (J-HITs) groupPLOS ONE Dear Dr. Nonaka, 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. ACADEMIC EDITOR: I really appreciated the importance of your work. Please address all comments pointed out by the reviewers. Here are some comments from myself. In the abstract and main text, please report odds ratios with 95% CIs. In contrast, p values can be removed. Significant figures should be standardized throughout the manuscript (including tables), e.g., to the second or third decimal place. In general, English-language papers do not use vertical lines in tables. Since there seems to be no compelling reason to do so, please reorganize the tables. Give Figure 1 a title (e.g., Participants flow chart). "multivariate" --> "multivariable" Please refer to Hidalgo and Goodman, 2013, Am J Public Health, 103(1), 39-40. DOI: 10.2105/AJPH.2012.300897 The use of abbreviations is not good, such as once-defined abbreviations being spelled out again, etc. Please review the manuscript in general. Please submit your revised manuscript by Sep 23 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. 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We will update your Data Availability statement to reflect the information you provide in your cover letter. 3. We note that you have stated that you will provide repository information for your data at acceptance. Should your manuscript be accepted for publication, we will hold it until you provide the relevant accession numbers or DOIs necessary to access your data. If you wish to make changes to your Data Availability statement, please describe these changes in your cover letter and we will update your Data Availability statement to reflect the information you provide. [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: Partly ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes ****** 3. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: No ****** 4. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: No ****** 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 a case series from a convenience sample of head injury cases from a larger case registry over 6+ years in Japan. The purpose is to review the presence or absence of a history of how the head trauma occurred and find associations with the mechanism, presentation and determination of accidental versus non-accidental trauma. The finding of the correlation of seizures and a lack of history of the trauma with non-accidental trauma (NAT) is novel and important. However, there are additional statements made regarding the need for a differential diagnosis related to NAT which are not the subject of the research and not included in their methods or results. The references are appropriate given the location of the cases, but there is an additional international reference which would be helpful. In addition, there appear to be issues with the use of English language to be addressed. I have specific comments as follows. The abstract begins with "true mechanism" where what the authors are trying to say is that the medical history of injury given by parents of head trauma infants may not be accurate or completely true. We do understand the mechanism. No need to mention the prior study in the abstract. Were there any hypotheses? There needs to be a better description of the Child Guidance Center and what a report means. Is this what we consider to be a mandated report of suspected abuse to the government for investigation? This should be better explained in the introduction and methods. The determination of whether the injury is NAT or accidental needs to be better described as this decision is critical to the paper. How were the criteria in Table 1 created? There may be misclassified cases that can easily change the outcome of the study given the small number of cases. You do mention that you take the "last" history provided; how does that bias your results? Perhaps a family has no information and then dreams up a history to match the findings? How do you deal with disagreements among the hospital teams and the investigators and child guidance center? Was there any disagreement? The abstract talks about the mechanisms increasing the risk of NAT. It is better throughout the paper to refer to these consistently as statistical associations rather than causes or risks. The abstract also add in a sentence as does the discussion have a paragraph about the differential diagnosis and how they need to be considered. Yet there is no mention whether any of the cases had such an alternative diagnosis and the information is not included in the analysis. While a general statement early on about the important of looking for underlying medical causes is appropriate, such detailed statements with multiple citations are not part of the study and should be deleted. In the introduction, I would also add the following reference since there is newer information than is discussed: Choudhary AK, et al. Consensus statement on abusive head trauma in infants and young children. Pediatr Radiol. 2018 Aug;48(8):1048-1065. doi: 10.1007/s00247-018-4149-1. In methods, I appreciate the description of how the sample was derived from the larger case registry. It would be very helpful to the reader to understand early on what the inclusion criteria were: Under age 4y, SDH on head imaging, reporting to child guidance center, and presence of retinal exam. This severely biases the cases chosen to more serious cases and likely more NAT cases as these are the ones more likely to meet all of these criteria. When cases are not reported to child guidance center, they are likely to be accidental, so this biases your results. Are there exclusion criteria for medical causes? And the small number of cases limits the power of your statistical analyses. This should be listed under limitations. Also, how were the 14 categories of mechanism determined? There is no explanation in the intro of how these are important. This should be described as well as how the criteria for NAT were decided. The results section seems appropriate, but why do you discuss all 452 cases? How does that help your findings> You should only focus on the 84. The conclusions of the paper are that, among children younger than 4 years of age who are reported to the child guidance center, convulsions are significantly associated with NAT in univariate and multivariate models. There is no basis to conclude anything about other medical conditions that were not studied. ****** 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: 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. 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Revision 1
6 Sep 2022 Author Response Academic Editor Comment #1 In the abstract and main text, please report odds ratios with 95% CIs. In contrast, p values can be removed. Author’s Response: The odds ratio with 95% CIs has been added in the abstract and main text according to the academic editor’s suggestions. Comment # 2 Significant figures should be standardized throughout the manuscript (including tables), e.g., to the second or third decimal place. Author’s Response: The significant figures has been standardized to the second or third decimal place according to the academic editor’s suggestions. Comment # 3 In general, English-language papers do not use vertical lines in tables. Since there seems to be no compelling reason to do so, please reorganize the tables. Author’s Response: The vertical lines in tables　2 and 3 has been removed according to the academic editor’s suggestions. Comment # 4 Give Figure 1 a title (e.g., Participants flow chart). Author’s Response: We have given the title in Figure 1. Comment # 5 "multivariate" --> "multivariable" Please refer to Hidalgo and Goodman, 2013, Am J Public Health, 103(1), 39-40. DOI: 10.2105/AJPH.2012.300897 Author’s Response: We have changed the word "multivariate" to "multivariable" according to the editor's suggestion. Comment # 6 The use of abbreviations is not good, such as once-defined abbreviations being spelled out again, etc. Please review the manuscript in general. Author’s Response: We apologize for the inappropriate use of abbreviations. We have corrected the use of abbreviations. Reviewer #1: 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: Partly Author’s Response: The conclusions have been revised in accordance with the reviewer's comments. The changes are listed below in response to the direct comments. ________________________________________ 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes ________________________________________ 3. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: No Author’s Response: The data used for this paper has been uploaded as supporting information file (S1). ________________________________________ 4. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: No Author’s Response: The English grammar of this paper has been revised ________________________________________ 5. Review Comments to the Author Reviewer #1: This is a case series from a convenience sample of head injury cases from a larger case registry over 6+ years in Japan. The purpose is to review the presence or absence of a history of how the head trauma occurred and find associations with the mechanism, presentation and determination of accidental versus non-accidental trauma. The finding of the correlation of seizures and a lack of history of the trauma with non-accidental trauma (NAT) is novel and important. However, there are additional statements made regarding the need for a differential diagnosis related to NAT which are not the subject of the research and not included in their methods or results. The references are appropriate given the location of the cases, but there is an additional international reference which would be helpful. In addition, there appear to be issues with the use of English language to be addressed. I have specific comments as follows. Comment #1 The abstract begins with "true mechanism" where what the authors are trying to say is that the medical history of injury given by parents of head trauma infants may not be accurate or completely true. We do understand the mechanism. Author’s Response: Thank you very much for your valuable suggestions. We have made the following changes to the text below. Change to text：Page 2, Lines 2-3 (with track change) The medical history of injury given by parents of infants and toddlers with head trauma may not be accurate or completely true. Comment #2 No need to mention the prior study in the abstract. Were there any hypotheses? Author’s Response: We prepared this paper in response to a previous study, but as the reviewer pointed out, we have removed the citation in the abstract as we deemed it unnecessary. Change to text: Page 2, Lines 6-8 (with track change) Our multicenter study group retrospectively reviewed the clinical records of children younger than 4 years with head trauma who were diagnosed with any finding on head computed tomography (CT) and/or magnetic resonance imaging (MRI). Comment #3 There needs to be a better description of the Child Guidance Center and what a report means. Is this what we consider to be a mandated report of suspectedabuse to the government for investigation? This should be better explained in the introduction and methods. Author’s Response: We have added a description of the Child Guidance Centers in Japan and what cases are notified to them. Change to text: Page 3, Lines 5-10 (with track change) Child Guidance Centers in Japan are administrative agencies established in prefectures and government-designated cities for the purpose of promoting the welfare of children and protecting their rights. In cooperation with local communities, Child Guidance Centers provide consultation services to families and others, accurately identify children's problems and environments, and assist children and families. When a child who appears to have been abused is found, it is mandatory to immediately notify the Child Guidance Center Comment #4 (1) The determination of whether the injury is NAT or accidental needs to be better described as this decision is critical to the paper. How were the criteria in Table 1 created? There may be misclassified cases that can easily change the outcome of the study given the small number of cases. Author’s Response: Table 1 reflects the results of separating abuse and accidents as much as possible. It is possible that some of the cases in the accident group that were not temporarily protected by the e Childs Guidance Center may have been caused by NAT, and some of the cases that were temporarily protected by the Childs Guidance Center may have been caused by accident. However, in Japan, the Childs Guidance Center not only determines the possibility of abuse based on the child's social information, but also conducts a medical evaluation by a third-party medical expert to more accurately determine whether or not abuse has occurred. We believe that we have achieved a certain level of accuracy. Therefore, we consider that this classification has the lowest margin of error at this time. Change to text: Page 4, Lines 12-19 (with track change) Some of the cases in the accident group that were not temporarily protected by the Childs Guidance Center may have been caused by nonaccidental trauma, and some of the cases that were temporarily protected by the Childs Guidance Center may have been caused by accident. However, in Japan, the Childs Guidance Center not only determines the possibility of abuse based on the child's social information, but also conducts a medical evaluation by a third-party medical expert to more accurately determine whether or not abuse has occurred. Therefore, we consider that only a few cases have been misclassified. Comment #4 (2) You do mention that you take the "last" history provided; how does that bias your results? Perhaps a family has no information and then dreams up a history to match the findings? Author’s Response: The injury mechanism described by the caregivers was carefully reviewed in the CPT at each facility. If there was any doubt, the case was notified to the Child Guidance Center. If the Child Guidance Center decided to take temporary custody of the case, or if the prosecution filed a criminal complaint as an abuse case, the case was classified as nonaccidental in this study. This allowed us to examine how many cases of nonaccidental injuries exist in the caregivers' last stated injury scenario. Change to text: Page 5, Lines 7-10. (with track change) However, because caregivers do not always state the correct injury mechanism, we classified the case as nonaccidental if the child guidance center decided to take the case into temporary custody, or if the prosecution filed criminal charges as an abuse case. Comment #4 (3) How do you deal with disagreements among the hospital teams and the investigators and child guidance center? Was there any disagreement? Author’s Response: If there is a difference of opinion, the opinion of the police or other investigating agency takes precedence, followed by the opinion of the Child Guidance Center, which takes precedence over the opinion of the CPT of the respective institution. However, even if the prosecutor does not prosecute, the Child Guidance Center may take custody of the child if abuse is suspected. Change to Text: Page 5, Lines 10-14 (with track change) If the opinions differ, the opinion of the investigating agency, such as the police, takes precedence, followed by the opinion of the child guidance center, which takes precedence over the opinion of the CPT of the respective institution. Comment #5 The abstract talks about the mechanisms increasing the risk of NAT. It is better throughout the paper to refer to these consistently as statistical associations rather than causes or risks. Author’s Response: We have changed the term “risk factor” to “statistical association” Change to text : Page 2, Lines 13-14 (with track change) The mechanisms of the injuries were examined by multivariable analysis to identify which ones were statistically associated with nonaccidental injuries. Comment #6 The abstract also add in a sentence as does the discussion have a paragraph about the differential diagnosis and how they need to be considered. Yet there is no mention whether any of the cases had such an alternative diagnosis and the information is not included in the analysis. While a general statement early on about the important of looking for underlying medical causes is appropriate, such detailed statements with multiple citations are not part of the study and should be deleted. Author’s Response: In the abstract, we deleted the description of differential diagnosis of medical causes which was not addressed in this study. Change to text; Page 2, Lines 22. (with track change) The sentence “However, in patients with an unexplained injury mechanism, it is necessary to make a careful differential diagnosis from intrinsic diseases” was removed. Comment #7 In the introduction, I would also add the following reference since there is newer information than is discussed: Choudhary AK, et al. Consensus statement on abusive head trauma in infants and young children. Pediatr Radiol. 2018 Aug;48(8):1048-1065. doi: 10.1007/s00247-018-4149-1. Author’s Response: We cited the literature as suggested by the reviewers and discussed its contents. Change to text : Page 9, Lines 18-21. (with track change) In cases with multiple factors such as subdural hematoma, intracranial changes, complicated retinal hemorrhages, and rib and other fractures that are inconsistent with the described injury mechanism, experts state that the medical validity of the presence of AHT is not in dispute[4]. Comment #8 (1) In methods, I appreciate the description of how the sample was derived from the larger case registry. It would be very helpful to the reader to understand early on what the inclusion criteria were: Under age 4y, SDH on head imaging, reporting to child guidance center, and presence of retinal exam. This severely biases the cases chosen to more serious cases and likely more NAT cases as these are the ones more likely to meet all of these criteria. When cases are not reported to child guidance center, they are likely to be accidental, so this biases your results. Author’s Response: Many cases were not notified to the Child Guidance Center because of the high possibility of accidents, but it is possible that the CPT at each facility does not have a firm determination of abuse or accident. For this reason, we did not include cases that were not reported to the Child Guidance Center in this study. Change to Text: Page 11, Lines 16-21. (with track change) In this study, only cases that were notified to the Child Guidance Center, which conducted a more multifaceted review of cases of injuries sustained in the home, were included. As a result, the study tended to exclude many minor accident cases that were determined not to require notification, while abused cases tended to be more prevalent. Comment #8 (2) Are there exclusion criteria for medical causes? Author’s Response: There are no common medical exclusion criteria across facilities. However, it is common practice in Japan to check family history and exclude hemorrhagic disease or skeletal dysplasia when a case of abuse is suspected. Change to Text: Page 5, Lines 2-3. (with track change) The possibility of the disease causing subdural hematoma was determined at each facility. Comment #8 (3) And the small number of cases limits the power of your statistical analyses. This should be listed under limitations. Author’s Response: The number of cases included in this report limits the power of statistical analysis. Change to text: Page 11, Lines 20-21. (with track change) The small number of included cases may limit the power of our statistical analysis. Comment #9 Also, how were the 14 categories of mechanism determined? There is no explanation in the intro of how these are important. This should be described as well as how the criteria for NAT were decided. Author’s Response: In this study, we asked each facility to freely describe the sequence of events that led to the injury. After reviewing the descriptions, we found that they can be categorized into 14 items. Change to text: Page 5, Lines 14-16. (with track change) The injury mechanism described by the caregivers was freely described at each facility. The descriptions were classified into 14 categories in descending order of frequency, and each category was studied. Comment #10 The results section seems appropriate, but why do you discuss all 452 cases? How does that help your findings> You should only focus on the 84. Author’s Response: To consolidate to 84 cases, we removed the number of causes of trauma for all 452 enrolled cases listed in Table 2 Change to Text: We have removed data on all 452 cases from Table 2. Comment #11 The conclusions of the paper are that, among children younger than 4 years of age who are reported to the child guidance center, convulsions are significantly associated with NAT in univariate and multivariate models. There is no basis to conclude anything about other medical conditions that were not studied. Author’s Response: The description about medical condition in conclusions has been deleted. Change to text: Page 11, Lines 25. (with track change) The sentence “However, in patients with an unexplained injury mechanism, if head trauma is observed on imaging, it is necessary to carefully make a differential diagnosis from intrinsic diseases that present with findings similar to those of trauma. “ has been deleted Attachments Attachment Submitted filename: Response to Reviewers.docx https://doi.org/10.1371/journal.pone.0277103.r002
11 Oct 2022 Decision Letter - Kenta Matsumura, Editor PONE-D-22-14343R1Unexplained mechanism of subdural hematoma with convulsion suggests nonaccidental head trauma: A multicenter, retrospective study by the Japanese Head injury of Infants and Toddlers study (J-HITs) groupPLOS ONE Dear Dr. Nonaka, 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 Nov 25 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, Kenta Matsumura Academic Editor PLOS ONE Journal Requirements: Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice. Additional Editor Comments: Thank you for the revised manuscript. The reviewers are generally favorable to the revised manuscript, but there are still some minor corrections to be made. Because PLoS One does not edit manuscripts after acceptance, any spelling errors should be corrected by this time. We strongly recommend that authors use an editing service or have their manuscript checked by a native speaker with expertise in the field. If possible, please submit the revised manuscript with a certificate of proofreading by a third party. [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: All comments have been addressed ******** 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: Thank you for addressing my concerns. The paper is substantially better, but still has some minor corrections needed: p5. add space between the and disease at the end of line 2. Add a period at the end of the paragraph "and a statement regarding patient consent." p6. In table 2, please align the cause of injury to the left to aid readability. p7. In table 3, please increase spacing in the heading so letters are not dropped to the next line. p8. Please align all paragraphs to the left. p9. Please add a space in the second paragraph of the discussion between accidents and (10). p10.Change second line to say "...inconsistent with the described injury mechanism, there is consensus that the medical validity..." p11. remove space at end of sentence in line 3. Correct spelling to "were" in the line 3 of the third paragraph. ****** 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.0277103.r003
Revision 2
15 Oct 2022 Author Response Reviewer #1: Comment #1 p5. add space between the and disease at the end of line 2. Author’s Response: The text has been revised according to the reviewer`s suggestion. Comment #2 Add a period at the end of the paragraph "and a statement regarding patient consent." Author’s Response: The text has been revised according to the reviewer`s suggestion. Comment #3 p6. In table 2, please align the cause of injury to the left to aid readability. Author’s Response: The table has been revised according to the reviewer`s suggestion. Comment #4 p7. In table 3, please increase spacing in the heading so letters are not dropped to the next line. Author’s Response: The table has been revised according to the reviewer`s suggestion. Comment #5 p8. Please align all paragraphs to the left. Author’s Response: The paragraphs has been revised according to the reviewer`s suggestion. Comment #6 p9. Please add a space in the second paragraph of the discussion between accidents and (10). Author’s Response: The paragraphs has been revised according to the reviewer`s suggestion. Comment #7 p10.Change second line to say "...inconsistent with the described injury mechanism, there is consensus that the medical validity..." Author’s Response: The text has been revised according to the reviewer`s suggestion. Comment #8 p11. remove space at end of sentence in line 3. Author’s Response: The text has been revised according to the reviewer`s suggestion. Comment #9 Correct spelling to "were" in the line 3 of the third paragraph. Author’s Response: The text has been revised according to the reviewer`s suggestion. Attachments Attachment Submitted filename: Response to Reviewers.docx https://doi.org/10.1371/journal.pone.0277103.r004
20 Oct 2022 Decision Letter - Kenta Matsumura, Editor Unexplained mechanism of subdural hematoma with convulsion suggests nonaccidental head trauma: A multicenter, retrospective study by the Japanese Head injury of Infants and Toddlers study (J-HITs) group PONE-D-22-14343R2 Dear Dr. Nonaka, 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, Kenta Matsumura Academic Editor PLOS ONE Additional Editor Comments (optional): Reviewers' comments: https://doi.org/10.1371/journal.pone.0277103.r005
Formally Accepted
24 Oct 2022 Acceptance Letter - Kenta Matsumura, Editor PONE-D-22-14343R2 Unexplained mechanism of subdural hematoma with convulsion suggests nonaccidental head trauma: A multicenter, retrospective study by the Japanese Head injury of Infants and Toddlers study (J-HITs) group Dear Dr. Nonaka: 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. Kenta Matsumura Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0277103.r006

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