Review for 10.1186/s12876-020-1177-8 (2020)

Reviewer ’s report  
 
Title: Prognostic value of peripheral blood natural killer cells in colorectal cancer  
 
Version: 0 Date: 19 Nov 2019  
 
Reviewer: Piyush Sharma  
 
Reviewer's report:  
 
The study is neither designed to properly ascertain independent a ssociation nor is powered  to do 
so, given the large number of various confounding parameters. My  greatest concern is with their 
gating strategy which incidentally they do not provide any flo w data for and furthermore, the 
article they quote as reference doesnt do so either. I say so becaus e by only including CD16+ 
cells they completely leave out CD3 -CD56brightCD16dim  NK cell population. No information 
regarding time since surgery and/or adjuvant chemoth erapy or any tumor histological 
characteristics is provided either. Even despite all these concerns, while they do show an 
association with survival, it contradicts rep orts from other groups such as Krigjsman et al 
(Cancer Immunology, Immunotherapy (2019) 68:1011 -1024)  
 
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 nece ssary 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.  
 
No 
 
Are you able to assess any s tatistics 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 statist ics 
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
 
Not suitable for publication unless extensively edited  
Declaration of competing interests  
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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 
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future?  
 
3.  Do you hold or are you currently applying for any patents  relating to the content 
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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 com peting 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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