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1 PEER REVIEW HISTORY BMJ Open publishes all reviews undertaken for accepted manuscripts. Reviewers are asked to complete a checklist review form ( and are provided with free text boxes to elaborate on their assessment. These free text comments are reproduced below. TITLE (PROVISIONAL) AUTHORS REVIEWER REVIEW RETURNED GENERAL COMMENTS REVIEWER ARTICLE DETAILS Characteristics of pneumonia deaths after earthquake and tsunami: an ecological study of 5.7 million subjects in 131 municipalities, Japan Shibata, Yosuke; Ojima, Toshiyuki; Tomata, Yasutake; Okada, Eisaku; Nakamura, Mieko; Kawado, Miyuki; Hashimoto, Shuji VERSION 1 - REVIEW Shinichi Omama Department of Critical Care Medicine, Iwate Medical University School of Medicine, Morioka, Japan. 19-Jul-2015 This is an important and novel study with high validity data examining the effect of a major earthquake and tsunami on pneumonia mortality, which was particularly increased in a coastal area. The authors suggested that pneumonia increased after the disaster because of tsunami lung and the foul evacuation environment in the coastal area. This topic will be useful in providing information for emergency preparedness for disasters of the future. However, there are some questions regarding this paper as follows: 1) This paper lacks an explanation for the reason of an increase in pneumonia in not only the coastal area but also the inland area. There was less building damage and less evacuation in the inland area, where the environmental conditions considerably differed from former disasters of South Asian Earthquake of 2005 and Hanshin Awaji Earthquake. 2) Impact of the atomic power plant accident. The tsunami killed many people and destroyed many houses, and many residents in Iwate and Miyagi Prefecture were evacuated, but few people and houses were affected in the Fukushima prefecture. However, an enormous number of residents in a widespread area in Fukushima were forced to evacuate to safer places far from the disabled atomic power plant, and many elderly and disabled people died throughout the evacuation. The impact of the atomic power plant accident on pneumonia should be discussed. 3) The authors concluded that elderly people resident in a coastal area, in particular, require emergency preparedness for pneumonia; however, there are no data showing increased pneumonia in elderly people in this paper. The characteristics of elderly people who died from pneumonia and their SMRs should be presented. Takahisa Kawano Department of Emergency Medicine, University of Fukui Hospital, Japan

2 REVIEW RETURNED GENERAL COMMENTS 22-Jul-2015 Thank you for your manuscript on the increased risk for pneumonia deaths after the Great Eastern Earthquake and Tsunami. In this article, the authors compared the number of pneumonia death between pre- and post- disaster periods in total, coastal or inland areas in Miyagi, Iwate, and Fukushima prefectures. This is an interesting perspective that should be considered. However, there are a several concerns about the report that should be addressed. Abstract section The abstract lacked important information. The study period, the definition of SMR, the methods of statistical analysis, the unit for SMRs, and the difference in SMRs between coastal and inland cities were not provided. Please specify the required information which meets the guidelines for abstract such as Strobe guideline. Background section The first five paragraphs (page 4) included several unrelated information to this study (e.g. the detailed description of the Great Eastern Japan Earthquake, the wound infection). It made your study background and the relation with the topic you chose (death caused by pneumonia) unclear. Please summarize and combine with paragraphs into no more than two paragraphs. In the first sentence of last paragraph in background, you used thus (page 4, line 40). I could not understand the logical connection between the first four paragraphs and this paragraph. In addition, it is not appropriate to start the paragraph using a conjunction. Comment 3 In the last paragraph, the aim of the study was unclear. Did you examine the increased incidence of pneumonia, the risk of pneumonia or the association between earthquake and pneumonia? According to your manuscript, you investigated the association between the coastal/inland area and the number of deaths due to pneumonia, not the total number of pneumonia patients. Methods section As mentioned above, the authors did not provide the study period (page 4, line52). In statistical analysis, the denominator, the numerator, and the unit of SMRs were not stated. Furthermore, the methods of statistical analysis were not mentioned. These are standard information that should be included (page 5 line 33-42). Result section In the characteristics of population, the authors did not provide the difference in population between the coastal and the inland areas with number, statistical significance and unit (page 5, line 56). Thus, readers did not know whether the difference was statistically significant or not. Furthermore, the pneumonia deaths and the SMRs

3 lacked their units (page 6, line 4, line 10). Discussion section In the first paragraph, the author stated risk was increased (page 6, line 28). However, the integrity of this statement was not supported, because the methods of statistical analysis were not provided in this manuscript. In the second paragraph (page 6, line 43), the author stated Tsunami survivors could thus not go to the hospital and obtain sufficient medical care. However, within several days from the initial disaster, the medical care started to be provided at mainly emergency shelters by several healthcare agencies. The authors need to elaborate on the reason of your result. Comment 3 The composition of the second paragraph (page 6, line 30) needs reconstruction. Please wire this paragraph to meet to the requirement for academic journals. Conclusion section In this section, you stated Our observation underscores the need for emergency prepared ness for pneumonia. Could you provide the name and the citation of the guideline or the recommendation by the governmental and/or non-governmental institutions? You stated elderly people residing in coastal areas especially need this preparedness. This is an inappropriate statement, because there are no associations between your statement and the study results. I suggest deleting or modifying this statement. Statistical analysis This data seems to consist of a panel data. I think the time-series analysis adjusted for cluster effect is suitable for this analysis. If you did so, please provide the name of the statistical analysis with the distribution and the link function. Overall This manuscript would benefit overall from English language editing. Thank you for the opportunity to review this work. VERSION 1 AUTHOR RESPONSE RESPONSE TO REVIEWER 1: We wish to express our appreciation to the Reviewer for the insightful comments, which have helped us significantly improve the paper. : This paper lacks an explanation for the reason of an increase in pneumonia in not only the coastal area but also the inland area. There was less building damage and less evacuation in the inland area, where the environmental conditions considerably differed from former disasters of South Asian Earthquake of 2005 and Hanshin Awaji Earthquake. Response: Pneumonia death reportedly increases after earthquake in both a coastal and an inland

4 area. Although the mechanism is not completely understood, it is thought that some factors contributed; lack of the appropriate nutrition, the loss of regular medicines, psychological stress and cold temperature. We modified our manuscript as suggested. Manuscript change (Page 6, Lines 22-25): Our study showed that the risk of pneumonia death increased after the earthquake. Our study was consistent with the previous studies. Previous studies suggested that several factors contributed to pneumonia death, although the causal mechanism was not fully established. Lack of appropriate nutrition, the loss of regular medicines, psychological stress and cold temperature might increase the risk of pneumonia death. : Impact of the atomic power plant accident. The tsunami killed many people and destroyed many houses, and many residents in Iwate and Miyagi Prefecture were evacuated, but few people and houses were affected in the Fukushima prefecture. However, an enormous number of residents in a widespread area in Fukushima were forced to evacuate to safer places far from the disabled atomic power plant, and many elderly and disabled people died throughout the evacuation. The impact of the atomic power plant accident on pneumonia should be discussed. Response: Some residents in coastal municipalities in Fukushima Prefecture had to escape due to a nuclear power plant accident. It lead to a high population density in the shelter and increased the risk of pneumonia death. We modified our manuscript as suggested. Manuscript change (Page 6, Lines 26-28): Additionally, at the accident of atomic power plant in Fukushima Prefecture forced residents to evacuate from their living area. It led to a high population density in the shelter and might increase the risk of pneumonia death. Comment 3: The authors concluded that elderly people resident in a coastal area, in particular, require emergency preparedness for pneumonia; however, there are no data showing increased pneumonia in elderly people in this paper. The characteristics of elderly people who died from pneumonia and their SMRs should be presented. Response: The present study could not mention the age of the pneumonia death. We deleted it. Manuscript change (Page 7, Line 28): Deleted. RESPONSE TO REVIEWER 2: We wish to express our strong appreciation to the reviewers for their insightful comments on our paper. We feel the comments have helped us significantly improve the paper. Abstract section : The abstract lacked important information. The study period, the definition of SMR, the methods of statistical analysis, the unit for SMRs, and the difference in SMRs between coastal and inland cities were not provided. Please specify the required information which meets the guidelines for abstract such as Strobe guideline. Response 1: We thank the reviewer for this helpful comment. The study period was 12 March 2010 to 9 March We modified our manuscript as follows. Manuscript change (Page 2, Lines 7-8): Data on population and pneumonia deaths obtained from the Vital Statistics 2010 and 2012, National Census 2010 and Basic Resident Register 2010 and 2012 in Japan Response 2: The number of observed pneumonia deaths (O) and the sum of the sex and ageclasses in the observed population multiplied by the sex and age-classes expected pneumonia death mortality (E) were calculated. Then, the expected pneumonia death mortality was pneumonia death mortality during 1 year before. The SMRs calculated for pneumonia deaths was O/E. We modified our

5 manuscript as follows. Manuscript change (Page 2, Lines 14-18): The number of observed pneumonia deaths (O) and the sum of the sex- and age-classes in the observed population multiplied by the sex- and age-classes of expected pneumonia death mortality (E) were calculated. Expected pneumonia death mortality was the pneumonia death mortality during the year before. Standard mortality ratios (SMRs) were calculated for pneumonia deaths (O/E), adjusting for sex and age using the indirect method. Response 3: Statistical analysis was SMRs compared by coastal and inland municipalities. SMRs did not have a unit because it was a ratio. Manuscript change (Page 2, Lines 18-19): SMRs were then calculated by coastal and inland municipalities. Response 4: The difference in SMRs between coastal and inland cities were added to the Results section. Manuscript change (Page 2, Lines 21-23): In the 2nd week, SMRs in coastal and inland municipalities were 2.49 (95% CI 2.02 to 7.64) and 1.48 (95% CI 1.24 to 2.61), respectively. SMRs of coastal municipalities were higher than those of inland municipalities. Background section : The first five paragraphs (page 4) included several unrelated information to this study (e.g. the detailed description of the Great Eastern Japan Earthquake, the wound infection). It made your study background and the relation with the topic you chose (death caused by pneumonia) unclear. Please summarize and combine with paragraphs into no more than two paragraphs. Response: We modified the Background section to 2 paragraphs. The first paragraph was about the Great East Japan Earthquake, and the second covered the association between the earthquake/tsunami and the infections disease. Manuscript change (Page 4, Paragraphs 1-4): Combined. : In the first sentence of last paragraph in background, you used thus (page 4, line 40). I could not understand the logical connection between the first four paragraphs and this paragraph. In addition, it is not appropriate to start the paragraph using a conjunction. Response: We deleted thus and modified our manuscript as suggested. Manuscript change (Page 4, Line 25): The pneumonia risk was increased by the earthquake and tsunami, respectively. Comment 3: In the last paragraph, the aim of the study was unclear. Did you examine the increased incidence of pneumonia, the risk of pneumonia or the association between earthquake and pneumonia? According to your manuscript, you investigated the association between the coastal/inland area and the number of deaths due to pneumonia, not the total number of pneumonia patients. Response: We appreciate the reviewer s comment on this point. The present study examined the risk of pneumonia death after the earthquake/tsunami. We modified our manuscript as suggested. Manuscript change (Page 2, Lines 4-5): We examined the risk for pneumonia death after the earthquake/tsunami (Page 4, Lines 28-29): Hence, the aim of the present study was to determine the risk for pneumonia death after the earthquake/tsunami Methods section : As mentioned above, the authors did not provide the study period (page 4, line52).

6 Response: We thank the reviewer for this helpful comment. We have modified our manuscript as suggested. Manuscript change (Page 4, Lines 33-34): Data from the 131 municipalities (population about 5.7 million) in Japan 2010 to 2012 were used (Page 5, Lines 1-2): The Vital Statistics 2010 to 2012, National Census 2010 and Basic Resident Register 2010 to 2012 in Japan were used : In statistical analysis, the denominator, the numerator, and the unit of SMRs were not stated. Furthermore, the methods of statistical analysis were not mentioned. These are standard information that should be included (page 5 line 33-42). Response: The denominator, numerator and statistical analysis were added. The SMRs have no unit as mentioned above. We modified our manuscript as suggested. Manuscript change (Page 5, Lines 20-27): The number of observed pneumonia deaths (O) and the sum of the sex- and age-classes in the observed population multiplied by the sex- and age-classes expected pneumonia death mortality (E) were calculated. Expected pneumonia death mortality was pneumonia death mortality during 1 year before. Standard mortality ratios (SMRs) were calculated for pneumonia deaths (O/E), adjusting for sex and age using the indirect method. To evaluate earthquake and tsunami impact, SMRs and 95% CIs for pneumonia were then calculated by coastal and inland municipalities. The 95% CIs of SMRs were estimated using the Poisson distribution. Result section : In the characteristics of population, the authors did not provide the difference in population between the coastal and the inland areas with number, statistical significance and unit (page 5, line 56). Thus, readers did not know whether the difference was statistically significant or not. Furthermore, the pneumonia deaths and the SMRs lacked their units (page 6, line 4, line 10). Response 1: We are grateful for your proposal. We described the number of pneumonia deaths in coastal and inland municipalities. Manuscript change (Page 5, Lines 32-33): In the 3 prefectures mentioned above, 6,603 subjects died of pneumonia during the year after the earthquake, and 5,776 subjects during the year before (Table 1). Response 2: There were some tables both describing and not describing the statistical analyses, recently. We have 2 reasons for not describing the statistical analyses. First, the present study did not seek to the compare the population and number of pneumonia deaths in coastal and inland municipalities. Second, the present study analyzed about 570,000 subjects and had very high statistical power. It is clear that all factors show the statistical significant differences. Response 3: The ratio of the bottom line of Table 1 is the ratio of the number of pneumonia deaths before and after 1 year. To avoid confusing the SMRs in Table 2, we deleted it. Manuscript change (Page 10, Bottom of Table 1): Deleted Discussion section : In the first paragraph, the author stated risk was increased (page 6, line 28). However, the integrity of this statement was not supported, because the methods of statistical analysis were not provided in this manuscript. Response: Risks of pneumonia deaths were examined by the SMRs. We corrected the method section in detail. Manuscript change (Page 5, Lines 20-24): The number of observed pneumonia deaths (O) and the

7 sum of the sex- and age-classes in the observed population multiplied by the sex- and age-classes expected pneumonia death mortality (E) were calculated. Expected pneumonia death mortality was pneumonia death mortality during 1 year before. Standard mortality ratios (SMRs) were calculated for pneumonia deaths (O/E), adjusting for sex and age using the indirect method. : In the second paragraph (page 6, line 43), the author stated Tsunami survivors could thus not go to the hospital and obtain sufficient medical care. However, within several days from the initial disaster, the medical care started to be provided at mainly emergency shelters by several healthcare agencies. The authors need to elaborate on the reason of your result. Response: The medical care within several days was lifesaving. The present study examined pneumonia death risk for a long period. Tsunami survivors several days after the disaster had to go to hospital due to lack of regular medicines and need of professional treatment. Comment 3: The composition of the second paragraph (page 6, line 30) needs reconstruction. Please wire this paragraph to meet to the requirement for academic journals. Response: We thank the reviewer for this helpful comment. We thought about construction again and modified our manuscript, accordingly. The second paragraph showed the association between earthquake and pneumonia death and the third paragraph mentioned the association between tsunami and pneumonia death. Manuscript change (Page 6-7, DISCUSSION): Reconstructed second and third paragraphs Conclusion section : In this section, you stated Our observation underscores the need for emergency prepared ness for pneumonia. Could you provide the name and the citation of the guideline or the recommendation by the governmental and/or non-governmental institutions? Response: Medical care guideline at disaster for elderly 2011 (in Japanese) was declared by the Japan Geriatrics Society. Quoted the guideline. Manuscript change (Page 7, Lines 28): Quoted a guideline : You stated elderly people residing in coastal areas especially need this preparedness. This is an inappropriate statement, because there are no associations between your statement and the study results. I suggest deleting or modifying this statement. Response: We deleted, accordingly. Manuscript change (Page 7, Lines 28): Deleted Statistical analysis : This data seems to consist of a panel data. I think the time-series analysis adjusted for cluster effect is suitable for this analysis. If you did so, please provide the name of the statistical analysis with the distribution and the link function. Response: We thank the reviewer for bringing up this important point. The study design was an ecological and SMRs were calculated to evaluate the risk of pneumonia death. Overall : This manuscript would benefit overall from English language editing. Thank you for the opportunity to review this work.

8 Response: Thank you again for your comments on our paper. We had the English language edited again. REVIEWER REVIEW RETURNED GENERAL COMMENTS REVIEWER REVIEW RETURNED GENERAL COMMENTS VERSION 2 REVIEW Shinichi Omama Department of Critical Care Medicine, Iwate Medical University, Morioka, Japan 28-Aug-2015 Thank you for the opportunity to review your revised manuscript titled Characteristics of pneumonia deaths after earthquake and tsunami: an ecological study of 5.7 million subjects in 131 municipalities, Japan. Significant improvement was made in revised version. There is one point to reconsider. Result section Page 5, paragraph of Characteristics of population There are many overlapping information with Table 1. Please minimize the inclusion of duplicate information. Maybe author should explain the statistical difference of sex distribution, age composition of population, and the ratio of those aged 65 or older among three groups of municipalities in the text. Page 5, line 34. According to the Table 1, the number of subjects died during 1 year before was not 1,760 but 4,016. Please check. Takahisa Kawano University of Fukui Hospital, Japan 02-Sep-2015 Thank you for your manuscript on the increased risk for pneumonia deaths after the Great Eastern Earthquake and Tsunami. Your article has been improved. However, there are still several concerns about the report that should be addressed. Abstract section Did you calculate mean or median SMR? Please specify it as well as in other parts. In abstract as well as your latter part, you stated Earthquake increased the pneumonia risk. However, you assessed only the risk for pneumonia death. There is a possibility; the incidence of pneumonia might be the same between pre and post disaster period. However, the outcome of the pneumonia patients in post disaster period might be worse than that in pre disaster period. So, it seems more proper to use the risk for pneumonia death in your article. Background section The second paragraphs (page 4) included redundant information. Please make this paragraph shorter. In second paragraph, you mentioned the association between

9 disaster and pneumonia. Would you provide more specific association; the association between the place where disaster victims live and the incidence of pneumonia death or the association between disaster and the incidence of pneumonia death? Methods section Why did you calculate the expected pneumonia death mortality in pre disaster period? Does it mean you did not have the number of total pneumonia death in previous year? In statistical analysis section, you stated that SMRs were adjusted by sex and age. How did you do that? Please provide the methods as well as the citation for this adjustment? In addition, it would be better to provide non-adjusted SMRs in result section. Comment 3 I understand why you did not conducted the analysis for comparing the difference in SMRs between coastal and inland area. However, your sample size is only 131 because SMRs were calculated in each district. Though your study included the large number of population, you have to conduct statistical analysis if you want to show the difference. And, if you want to measure SMRs in the same district over a particular period repeatedly, you have to adjust a cluster effect and the autocorrelation of the units with equal time intervals; it means you have to conduct time series analysis. Overall You might be confused with the difference between the risk for pneumonia and the risk for death resulted from pneumonia. Would you rewrite your article to show this point clearly? Thank you for the opportunity to review this work. VERSION 2 AUTHOR RESPONSE RESPONSE TO REVIEWER 1: We wish to express our appreciation to the Reviewer for insightful comments, which have helped us significantly improve the paper. Result section : Page 5, paragraph of Characteristics of population There are many overlapping information with Table 1. Please minimize the inclusion of duplicate information. Maybe author should explain the statistical difference of sex distribution, age composition of population, and the ratio of those aged 65 or older among three groups of municipalities in the text. Page 5, line 34. According to the Table 1, the number of subjects died during 1 year before was not 1,760 but 4,016. Please check. Response: We thank the Reviewer for this pertinent comment. This error has been corrected in accordance with the reviewer's comment. The number of pneumonia death is most important information. Accordingly, we have changed this section to only pneumonia death information. Manuscript change (Page 5, Lines 31-32): A total of 4,488 subjects died of pneumonia during 1 year after in inland municipalities and 4,016 subjects died during 1 year before. (Page 5, Line 34): Deleted.

10 RESPONSE TO REVIEWER 2: We wish to express our strong appreciation to the reviewers for their insightful comments on our paper. We feel the comments have helped us significantly improve the paper. Abstract section : Did you calculate mean or median SMR? Please specify it as well as in other parts. Response: We regret the unclear in writing to you. The SMRs is ratios. Thus, mean and median were not exist. The explanation might be unclear. To clarify, we have added the following text to the Statistics. We also added a reference 15. Manuscript change (Page 5, Lines 17-25): Standardized mortality ratios (SMRs) were calculated to show how many times larger the pneumonia mortality is compared to that of 1 year before adjusting for sex and age. In detail, the sex- and age-specific pneumonia mortality before the earthquake (pre- 52nd to pre-1st weeks, standard period) were multiplied by the sex and age specific population after the earthquake (post-1st to post-52nd weeks, comparison period) to obtain the products by week. The total of the products were calculated to obtain the expected number of pneumonia deaths (E). The total number of observed pneumonia deaths (O) were calculated. SMRs were obtained by O divided by E. The 95% CIs of SMRs were estimated using the Poisson distribution. SMRs in coastal and inland municipalities were also calculated. : In abstract as well as your latter part, you stated Earthquake increased the pneumonia risk. However, you assessed only the risk for pneumonia death. There is a possibility; the incidence of pneumonia might be the same between pre and post disaster period. However, the outcome of the pneumonia patients in post disaster period might be worse than that in pre disaster period. So, it seems more proper to use the risk for pneumonia death in your article. Response: We strongly appreciate the reviewer's comment on this point. Description was unclear. Accordingly, we have corrected our article following the reviewer s advice. Manuscript change: Corrected our article to the risk of pneumonia death Background section : The second paragraphs (page 4) included redundant information. Please make this paragraph shorter. Response: In accordance with the reviewer's request, we have shortened the second paragraphs. Manuscript change (Page 4, Line 11): Deleted. : In second paragraph, you mentioned the association between disaster and pneumonia. Would you provide more specific association; the association between the place where disaster victims live and the incidence of pneumonia death or the association between disaster and the incidence of pneumonia death? Response: We mainly intend to mention the association between disaster and the pneumonia death. Manuscript change (Page 4, Line 11): Moved to page 6, lines (Page 6, Line 20): Our study showed that the association between disaster and the pneumonia death. Methods section : Why did you calculate the expected pneumonia death mortality in pre disaster period? Does it mean you did not have the number of total pneumonia death in previous year?

11 Response: The explanation might be unclear. To clarify, we have added the explanation of SMRs to the Statistics. We have added a reference 15.The number of total pneumonia death in previous year was obtained. Manuscript change (Page 5, Lines 17-25): As mentioned above. : In statistical analysis section, you stated that SMRs were adjusted by sex and age. How did you do that? Please provide the methods as well as the citation for this adjustment? In addition, it would be better to provide non-adjusted SMRs in result section. Response: As requested, we added the non-adjusted SMRs in result section. Manuscript change (Page 6, Lines 4-5): The ratios of the number of pneumonia death 1 year after to that of 1 year before was Comment 3: I understand why you did not conducted the analysis for comparing the difference in SMRs between coastal and inland area. However, your sample size is only 131 because SMRs were calculated in each district. Though your study included the large number of population, you have to conduct statistical analysis if you want to show the difference. And, if you want to measure SMRs in the same district over a particular period repeatedly, you have to adjust a cluster effect and the autocorrelation of the units with equal time intervals; it means you have to conduct time series analysis. Response: As the reviewer s advice, the time series analysis is one of the analysis methods. We recognize that time series analysis is useful to show the effects of continual exposure. We want to show that the risk of pneumonia death by once exposure of the Great East Japan Earthquake. Therefore, we used SMRs in this study. We strongly appreciate the reviewer's comment. We would like to be considered in next study. Overall: You might be confused with the difference between the risk for pneumonia and the risk for death resulted from pneumonia. Would you rewrite your article to show this point clearly? Response: In accordance with the reviewer s comment, we standardized the description to the risk of pneumonia death. REVIEWER REVIEW RETURNED GENERAL COMMENTS VERSION 3 - REVIEW Takahisa Kawano the Department of Emergency Medicine, St. Paul s Hospital, Vancouver, British Columbia, Canada 03-Dec-2015 Thank you for your manuscript. Your article has been improved. However, there are still some concerns about the report that should be addressed. Did you calculate SMRs in each municipal or just in all, coastal and inland area? It is quite confusing. If you calculated SMR in each municipal, I would say following suggestions. Please provide mean or mean SMR of total, coastal and inland area.

12 Compare SMR between coastal and inland areas and provide odds ratio in the same way in this article 1. If you did not calculate SMRs in each municipal, Please state more clearly that you treated coastal or inland municipals as one group in statistical section. It seems reasonable to change municipals to just area Please delete the number of municipals in Table 1. If you treat municipals as a chunk, the number of municipals has no meaning here. As the author is aware, it is better to calculate SMRs in each municipal because it enables to compare SMRs between coastal and inland municipals with statistical analysis. Comments 2 The author mentioned that the SMRs for pneumonia death significantly increased during the 1st to 12th week. However, there are some weeks when 95%CI of SMR was below 1.0. Thank you for the opportunity to review this work. 1. Krumholz HM, Wang Y, Chen J, et al. Reduction in acute myocardial infarction mortality in the United States: risk-standardized mortality rates from JAMA 2009;302(7): VERSION 3 AUTHOR RESPONSE RESPONSE TO REVIEWER: We wish to express our appreciation to the Reviewer for insightful comments. In particular, we wish to acknowledge the highly valuable suggestion with a reference. : Did you calculate SMRs in each municipal or just in all, coastal and inland area? It is quite confusing. If you calculated SMR in each municipal, I would say following suggestions. 1. Please provide mean or mean SMR of total, coastal and inland area. 2. Compare SMR between coastal and inland areas and provide odds ratio in the same way in this article 1. If you did not calculate SMRs in each municipal, 3. Please state more clearly that you treated coastal or inland municipals as one group in statistical section. 4. It seems reasonable to change municipals to just area 5. Please delete the number of municipals in Table 1. If you treat municipals as a chunk, the number of municipals has no meaning here. As the author is aware, it is better to calculate SMRs in each municipal because it enables to compare SMRs between coastal and inland municipals with statistical analysis. Response: We agree with the reviewer s comment. We think that SMRs in each municipalities is good method. However, the sample sizes of pneumonia death by sex, age and municipalities were small (see Figure 2). Thus, we calculated SMRs just in all, coastal and inland municipalities. Following the reviewer s 3rd suggestion, we clearly mentioned that SMRs were calculated in coastal and inland municipalities as one group. On the 4th suggestion, data of municipalities unit were obtained. Thus, we used municipality. As reviewer s 5th suggestion, we deleted the number of municipalities in Table 1.

13 Manuscript change (Page 5, Lines 24-25): SMRs were calculated for all municipalities and were additionally calculated for coastal and inland municipalities as one group. Manuscript change (Page 10, Table 1): Deleted the number of municipalities : The author mentioned that the SMRs for pneumonia death significantly increased during the 1st to 12th week. However, there are some weeks when 95%CI of SMR was below 1.0. Response: Following the Reviewer s comment, we deleted significantly. Manuscript change (Page 6, Line 7): Deleted. BMJ Open: first published as /bmjopen on 23 February Downloaded from on 8 March 2019 by guest. Protected by copyright.