Review for 10.1186/s12876-018-0765-3 (2018)

Reviewer ’s report  
Title: Recurrent common bile duct stones as a late complication of endoscopic sphincterotomy  
 
Version: 3 Date: 22 Feb 2018  
 
Reviewer: Cheng -Hsin Chu  
 
Reviewer's report:  
1. Since this study i s a retrospective study. All of existing data presenting in the study will 
difficult to explain the doubt and reason due to the limitations of time and endoscopic 
technique.  
2. Existing questions we ask, the authors have fully explained the basic results of this study. It is 
acceptable.  
3. In the future, a prospective research may dispel doubt remaining in this study.  
Cheng -Hsin CHU  
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the a uthors.  
Yes 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
No 
Are the conclusions drawn adequately supported by the data shown?  
If not, please explain in your comments to t he authors.  
Yes 
Are you able to assess any statistics in the manus cript or would you recommend an 
additional statistical review?  
If an additional statistical review is recommended, please speci fy what aspects require further 
assessment in your comments to the editors.  
Not relevant to this manuscript  
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
Acceptable  
Declaration of competing interests  
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3. Do you hold or are you currently applying for any patents  relating to the content of the 
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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 financial 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  
 
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