Review for 10.1186/s12876-020-1176-9 (2020)

Reviewer ’s report  
 
Title: Safety of endoscopic procedures with monopolar versus bi polar instruments in an ex vivo 
porcine model  
 
Version: 1 Date: 05 Jan 2019  
 
Reviewer: Wen -Lun Wang  
 
Reviewer's report:  
 
Comments to the Author  
 In this article, the authors reported a ex vivo porcine study to compare the safety of 
polypectomy, EMR and forcep coagulation, with monopolar versus bipolar instruments. In a 
total of 24 procedures on 5mm, 10mm, 15mm targeted lesions with duplicate evaluations, the 
authors found bipolar devices are safer than monopolar devices for colorectal polypectomy and 
EMR, with less damage to the muscularis propria layer. The topic o f this article is interesting, 
but I have the following comments.  
 
Major and specific comments:  
1. The major concern of this study is the statistic power.  
2. The title and abstract should point out this is an "ex vivo" study.  
3. Whether the efficiency and amount of saline injection will interfere with  the results?  
4. The definition of thermal denaturation and tissue damage should be clarified more.  
5. The authors mentioned "Tissue damage without perforation was found in most cases of 
M-P…" (In Page 6, Li ne 13). How many cases and the percentage should be described.  
 
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
No 
 
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 supported by the data shown?  
If not, please explain in your comments to the authors.  
 
No 
 
Are you able to assess any statistics in the manus cript or would you recommend an 
additional statist ical review?  
If an additional statistical review is recommended, please speci fy 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 complete 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 financial ly from the publication of this 
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 
financi ally from the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applying for any patents  relating to the content of the 
manuscript?  
 
4. Have you received reimbursements, fees, funding, or salary from an organiz ation 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 th e 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 inte rests 
 
 
 
 
I agree to the open peer review policy of the journal. I understan d that my name will be included 
on my report to the authors and, if the manuscript is accepted f or 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 l icense ( 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 in cluded as confidential comments 
to the editors, which will not be published.  
 
I agree to the open peer review policy of the journal