Review for 10.1186/s12876-019-1129-3 (2019)

Reviewer ’s report  
 
Title: Treatment of Post -Cholecystectomy Biliary Strictures with Fully -Covered Self -Expanding 
Metal Stents - Results after 5 years of Follow -up 
 
Version: 0 Date: 07 Aug 2019  
 
Reviewer: Praveer Rai  
 
Reviewer's report:  
 
Please  include all comments for the authors in this box rather than uploading your report as an 
attachment. Please only upload as attachments annotated versions of manuscripts, graphs, 
supporting materials or other aspects of your report which cannot be included  in a text format.  
 
Please overwrite this text when adding your comments to the authors.This is a prospective 
multicentric study a subgroup of patients with post cholecystectomy benign biliary stricture 
(PCBS) who underwent endoscopic placement of a fully c overed self -expanding metal stent 
(FCSEMS). The subject is not recent in world literature and there have been prior retrospective, 
prospective, randomized controlled trials (metal vs plastic) and metanalysis of patients 
undergoing metal stent for benign bi liary stricture. The report does not add to the existing 
knowledge of the subject.  
 
 
Limitation:  
 
1. Small sample size of only 18 patients out of which 15 patients had endoscopic removal 
and 3 had spontaneous migration  
 
2. How was the benign biliary stricture defined and how was the resolution of stricture 
defined?  
 
3. The frequency of adverse events was quite high 38.9% unlike prior studies in which 
frequency is less, needs to be explained.  
 
4. Since migration is a known complication of FCSEMS, why was any meas ure not taken to 
prevent migration like flared ends, anchoring fins or a plastic stent across the metal stent.  
 
5. Discussion part of the manuscript needs to incorporate prior studies and compare with the 
present study.  
 
Strength: Patients with PCBS with a  prolonged (5 yrs.) follow up.  
 
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.  
 
No 
 
Are the conclusions drawn adequately supported  by the data shown?  
If not, please explain in your comments to the 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 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:  
 
Acceptable  
 
Declaration of competing interests  
Please compl ete a declaration of competing interests, considering the following questions:  
 
1.  Have you in the past five years received reimbursements, f ees, funding, or salary 
from an organisation that may in any way gain or lose financially from the 
publication of th is manuscript, either now or in the future?  
 
2.  Do you hold any stocks or shares in an organisation t hat 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 applyi ng 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 finan cial 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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