Review for 10.1186/s12876-020-01343-7 (2020)

Reviewer ’s report  
 
Title: Open necrosectomy combined with continuous positive drai nage and prophylactic 
diverting loop ileostomy for late infected pancreatic necrosis: a retrospective cohort study  
 
Version: 1 Date: 13 Nov 2019  
 
Reviewer: Research Square Reviewer 1  
 
Reviewer's report:  
 
PEER REVIEWER ASSESSMENTS:  
 
OBJECTIVE - Full research articl es: is there a clear objective that addresses a testable research 
question(s) (brief or other article types: is there a clear objective)?  
No - there are minor issues  
 
DESIGN - Is the current approach (including controls and analysis protocols) appropriate for the 
objective?  
Yes - the approach is appropriate  
 
EXECUTION - Are the experiments and analyses performed with technical rigor to allow 
confidence in the results?  
No - there are major issues  
 
STATISTICS - Is the use of statistics in the manuscript appropriate?  
No - there are issues with the statistics in the study  
 
INTERPRETATION - Is the current interpretation/discussion of the results reasonable and not 
overstated?  
Yes - the author's interpre tation is reasonable  
 
OVERALL MANUSCRIPT POTENTIAL - Is the current version of this work technically 
sound? If not, can revisions be made to make the work technically sound?  
Maybe - with major revisions  
 
PEER REVIEWER COMMENTS:  
 
GENERAL COMMENTS:  
Abstrac t: In which group the CPD performed? Only in PDLI? or in all. Please clarify this in 
abstract.  
 
Please clarify this sentence in patient selection part.  
"The local complication and systematic inflammation cannot be improved by non -open surgery."  
 
Please rem ove "etc." in patient selection criteria, or state all the criteria.  
 
Please make a table for the variables described in Endpoints starting as: "For each participant, 
the following variables were collected,". They are given in figures but adding a table wi ll be 
more informative.  
 
Page 13, line 34: please avoid the term "more significant". A statistical test is either significant or 
not. It is not a continuum.  
 
Postoperative circulatory and pulmonary failure was compared with Kruskal -Wallis test. Did all 
the patients had failure? If not the survival analysis should be assessed via taking the censored 
cases into account. (Probably via cox -proportional hazard tests). And since there are primary and 
secondary end points, it may be necessary to perform a competin g risk analysis. Please consult a 
statistician.  
 
It is stated that "the cost in hospital was markedly reduced, and the time interval from operation 
to total enteral nutrition was significantly shorten" but the data are not given. Please provide 
related dat a. 
 
REQUESTED REVISIONS:  
The authors compare three techniques retrospectively. However the evaluation criteria are not 
clear. Mortality, primary and secondary end points are not stated appropriately.  
Some data are only given in figures and it is not easy to interpret them.  
Kruskal -Wallis was used to compare time periods. As explained in question 2, I suspect other 
tests with censored case and competing risk calculations are required.  
 
Are the methods appropriate and well described?  
If not, please specify what is required in y our 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.  
 
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 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 in terests, 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 financial ly from the publication of this 
manuscript, either now or in t he 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 applying for any patents relating to th e 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 financial competing interests?  
6. Do y ou 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.  
 
This reviewer has been recruited by a partner organization, Research Square. Reviewers with 
declared or apparent competing interests are not utilized for t hese reviews. This reviewer has 
agreed to publication of their comments online under a Creative Commons Attribution  License  
attributed to Research Square and was paid a small honorarium for  completing the review within 
a specified timeframe. Honoraria for reviews such as this are paid regardless of the reviewer  
recommendation.  
 
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 web site 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 in cluded as confidential comments 
to the editors, which will not be published.  
 
I agree to the open peer review policy of the journal