Review for 10.1186/s12876-019-1007-z (2019)

Reviewer ’s report  
 
Title: Fibrosis -4 index at diagnosis is associated with all -cause mortality in patients with 
microscopic polyangiitis and granulomatosis with polyangiitis  
 
Version: 0 Date: 02 Feb 2019  
 
Reviewer: Kenei Sada  
 
Reviewer's report:  
 
The authors have examined the association between fibrosis -4 index (FIB -4) at diagnosis  and all -
cause mortality in 132 immunosuppressive drug -naïve patients with microscopic  polyangiitis 
(MPA) and granulomatosis with polyangiitis (GPA).  
The authors concluded that FIB -4 ≥ 1.45 at diagnosis could be associated with all -cause 
mortality in patients with MPA and GPA by reflecting the contribution of old age, DM and  FFS 
(2009) at diagnosis ≥ 2 to the poor outcome. However, the authors just showed the possible risk 
factors for mortality with univariate analysis and did not evaluate the possibility of the 
confounding factors, which results in defective scientific evide nce. If FIB -4 only reflect old age, 
DM, and FFS (2009), it is not useful in clinical practice for AAV. Therefore, the reviewer 
disagrees with the authors' claim.  
Are the methods appropriate and well d escribed?  
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 dra wn 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 manuscript or would you recommend an  
additional statistical review?  
If an additional statistical review is recommended, please specify 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  
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1. Have you in the past five years received reimbursements, fees, funding, or salary from an  
organisation t hat may in any way gain or lose financially from the publication of this  
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3. Do you hold or are you currently applying for any patents relating to the content of the  
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4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds  or has applied for patents rel ating 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?  
 
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below.  If your reply is yes to any, please give details below.  
 
I declare that I have no competing interests.  
 
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