Reviewer ’s report  
Title: Optimal timing of cholecystectomy after percutaneous gallbladder drainage for severe  
cholecystitis  
 
Version: 0 Date: 07 Mar 2017  
 
Reviewer: Shinichi Morita  
 
Reviewe r's report:  
Comment 1  
In your study, the interval period from performing PTGBD to operation differed among the 
cases. How did you decide the timing of the operation in your cases?  
 
Comment 2  
From your results, I realized that surgical difficulty level was l ower if the interval period was no 
less than 216 hours. However, PTGBD needs an external drainage tube, and prolonged tube 
placement leads to several complications such as wound infection, pleural infusion, and 
accidental catheter removal. Furthermore, the  patients' quality of life was decreased.  
While awaiting surgery, did the troubles associated with tube placement differ between groups A 
and B?  
 
Comment 3  
There seem to be some reasons for converting from laparoscopic to open cholecystectomy. I 
recommend to describe the reasons for this conversion.  
 
Comment 4  
Necrotizing cholecystitis is defined a condition that makes the surgery difficult. I think it is not 
desirable to extend the interval to surgery. Please refer to this point in your discussion.  
 
Comme nt 5 
Tight adhesion is defined a condition that makes the surgery difficult. As you mentioned in your 
discussion, I think that the number of adhesion cases increased as the operation period was 
delayed. Please elaborate this point in your discussion.  
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
Yes 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
Yes 
Are the conclusions drawn adequately supporte d by the data shown?  
If not, please explain in your comments to the authors.  
Yes 
Are you able to assess any statistics in the manuscript or would you recommend an  
additional statistical review?  
If an additional statistical review is recommended, please spec ify what aspects require further  
assessment in your comments to the editors.  
I am able to assess the statistics  
Quality of written English  
Please indicate the quality of language in the manuscript:  
Accept able 
Declaration of competing interests  
Please comple te a declaration of competing interests, considering the following questions:  
1. Have you in the past five years received reimbursements, fees, funding, or salary from an  
organisation that may in any way gain or lose financially from the publication of thi s 
manuscript, either now or in the future?  
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose  
financially from the publication of this manuscript, either now or in the future?  
3. Do you hold or are you currently applyin g for any patents relating to the content of the  
manuscript?  
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds  or has applied for patents relating to the content of the manuscript?  
5. Do you have any other financ ial competing interests?  
6. Do you have any non -financial competing interests in relation to this paper?  
If you can answer no to all of the above, write 'I declare that I have no competing interests' 
below. If your reply is yes to any, please give details below.  
 
I declare that I have no competing interests.  
 
I agree to the open peer review policy of the jou rnal. I understand that my name will be included 
on my report to the authors and, if the manuscript is accepted for publication, my named report 
including any attachments I upload will be posted on the website along with the authors' 
responses. I agree for  my report to be made available under an Open Access Creative Commons 
CC-BY license ( http://creativecommons.org/licenses/by/4.0/ ). I understand that any comments 
which I do not wish to be included in my named report can be included as confidential comments  
to the editors, which will not be published.  
 
I agree to the open peer review policy of the journal  
Reviewer ’s report  
Title: Optimal timing of cholecystectomy after percutaneous gallbladder drainage for severe  
cholecystitis  
 
Version: 0 Date: 07 Mar 2017  
 
Reviewer: Shinichi Morita  
 
Reviewe r's report:  
Comment 1  
In your study, the interval period from performing PTGBD to operation differed among the 
cases. How did you decide the timing of the operation in your cases?  
 
Comment 2  
From your results, I realized that surgical difficulty level was l ower if the interval period was no 
less than 216 hours. However, PTGBD needs an external drainage tube, and prolonged tube 
placement leads to several complications such as wound infection, pleural infusion, and 
accidental catheter removal. Furthermore, the  patients' quality of life was decreased.  
While awaiting surgery, did the troubles associated with tube placement differ between groups A 
and B?  
 
Comment 3  
There seem to be some reasons for converting from laparoscopic to open cholecystectomy. I 
recommend to describe the reasons for this conversion.  
 
Comment 4  
Necrotizing cholecystitis is defined a condition that makes the surgery difficult. I think it is not 
desirable to extend the interval to surgery. Please refer to this point in your discussion.  
 
Comme nt 5 
Tight adhesion is defined a condition that makes the surgery difficult. As you mentioned in your 
discussion, I think that the number of adhesion cases increased as the operation period was 
delayed. Please elaborate this point in your discussion.  
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
Yes 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
Yes 
Are the conclusions drawn adequately supporte d by the data shown?  
If not, please explain in your comments to the authors.  
Yes 
Are you able to assess any statistics in the manuscript or would you recommend an  
additional statistical review?  
If an additional statistical review is recommended, please spec ify what aspects require further  
assessment in your comments to the editors.  
I am able to assess the statistics  
Quality of written English  
Please indicate the quality of language in the manuscript:  
Accept able 
Declaration of competing interests  
Please comple te a declaration of competing interests, considering the following questions:  
1. Have you in the past five years received reimbursements, fees, funding, or salary from an  
organisation that may in any way gain or lose financially from the publication of thi s 
manuscript, either now or in the future?  
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose  
financially from the publication of this manuscript, either now or in the future?  
3. Do you hold or are you currently applyin g for any patents relating to the content of the  
manuscript?  
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds  or has applied for patents relating to the content of the manuscript?  
5. Do you have any other financ ial competing interests?  
6. Do you have any non -financial competing interests in relation to this paper?  
If you can answer no to all of the above, write 'I declare that I have no competing interests' 
below. If your reply is yes to any, please give details below.  
 
I declare that I have no competing interests.  
 
I agree to the open peer review policy of the jou rnal. I understand that my name will be included 
on my report to the authors and, if the manuscript is accepted for publication, my named report 
including any attachments I upload will be posted on the website along with the authors' 
responses. I agree for  my report to be made available under an Open Access Creative Commons 
CC-BY license ( http://creativecommons.org/licenses/by/4.0/ ). I understand that any comments 
which I do not wish to be included in my named report can be included as confidential comments  
to the editors, which will not be published.  
 
I agree to the open peer review policy of the journal  
Please review this paper.
user
Reviewer ’s report  
Title: Optimal timing of cholecystectomy after percutaneous gallbladder drainage for severe  
cholecystitis  
 
Version: 0 Date: 07 Mar 2017  
 
Reviewer: Shinichi Morita  
 
Reviewe r's report:  
Comment 1  
In your study, the interval period from performing PTGBD to operation differed among the 
cases. How did you decide the timing of the operation in your cases?  
 
Comment 2  
From your results, I realized that surgical difficulty level was l ower if the interval period was no 
less than 216 hours. However, PTGBD needs an external drainage tube, and prolonged tube 
placement leads to several complications such as wound infection, pleural infusion, and 
accidental catheter removal. Furthermore, the  patients' quality of life was decreased.  
While awaiting surgery, did the troubles associated with tube placement differ between groups A 
and B?  
 
Comment 3  
There seem to be some reasons for converting from laparoscopic to open cholecystectomy. I 
recommend to describe the reasons for this conversion.  
 
Comment 4  
Necrotizing cholecystitis is defined a condition that makes the surgery difficult. I think it is not 
desirable to extend the interval to surgery. Please refer to this point in your discussion.  
 
Comme nt 5 
Tight adhesion is defined a condition that makes the surgery difficult. As you mentioned in your 
discussion, I think that the number of adhesion cases increased as the operation period was 
delayed. Please elaborate this point in your discussion.  
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
Yes 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
Yes 
Are the conclusions drawn adequately supporte d by the data shown?  
If not, please explain in your comments to the authors.  
Yes 
Are you able to assess any statistics in the manuscript or would you recommend an  
additional statistical review?  
If an additional statistical review is recommended, please spec ify what aspects require further  
assessment in your comments to the editors.  
I am able to assess the statistics  
Quality of written English  
Please indicate the quality of language in the manuscript:  
Accept able 
Declaration of competing interests  
Please comple te a declaration of competing interests, considering the following questions:  
1. Have you in the past five years received reimbursements, fees, funding, or salary from an  
organisation that may in any way gain or lose financially from the publication of thi s 
manuscript, either now or in the future?  
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose  
financially from the publication of this manuscript, either now or in the future?  
3. Do you hold or are you currently applyin g for any patents relating to the content of the  
manuscript?  
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds  or has applied for patents relating to the content of the manuscript?  
5. Do you have any other financ ial competing interests?  
6. Do you have any non -financial competing interests in relation to this paper?  
If you can answer no to all of the above, write 'I declare that I have no competing interests' 
below. If your reply is yes to any, please give details below.  
 
I declare that I have no competing interests.  
 
I agree to the open peer review policy of the jou rnal. I understand that my name will be included 
on my report to the authors and, if the manuscript is accepted for publication, my named report 
including any attachments I upload will be posted on the website along with the authors' 
responses. I agree for  my report to be made available under an Open Access Creative Commons 
CC-BY license ( http://creativecommons.org/licenses/by/4.0/ ). I understand that any comments 
which I do not wish to be included in my named report can be included as confidential comments  
to the editors, which will not be published.  
 
I agree to the open peer review policy of the journal  
assistant