Review for 10.1186/s12876-020-1167-x (2020)

Reviewer ’s report  
 
Title: The prognostic role of platelet -to-lymphocyte ratio on overal l survival in gastric cancer: a 
systematic review and meta -analysis  
 
Version: 0 Date: 29 May 2019  
 
Reviewer: Jian-Kun Hu  
 
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 annot ated versions of manuscripts, graphs, 
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Please overwrite this text when adding your comments to the authors.  
 
The purpose of this study was to summarize the previ ously published literature on the prognostic 
role of PLR in patients with GC. The authors concluded that an elevated PLR was associated 
with lower OS in patients with gastric cancer. These results might differ between studies due to 
differences in design, country of origin, sample size, sex proportion, treatment strategy, PLR 
cutoff value, and study quality. Here are the comments.  
 
1. Generally, the novelty of this study is low, a lot of studies have reported the clinical 
significance of PLR.  
2. The hetero geneity of all the included studies is very obvious. Although random model can be 
used, the intrinsic differences, like retrospective or prospective, chemotherapy, surgery, early or 
advanced GC, among these studies cannot be ignored.  
3. Please  show the c riteria in dividing subgroups, like sample size 1000, male 70%, etc.  
4. In Table 2 "Excluding study" should be corrected as "Including study", and the reference 
number should be labeled to distinguish.  
5. The forest figures of each subgroup analysis shou ld be shown.  
 
 
 
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 t he authors.  
 
No 
 
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:  
 
Needs some language corrections before being published  
 
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, f ees, funding, or salary from an 
organisation that may in any way gain or lose financially from the publi cation 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 
financially from the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you curr ently applying 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 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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