Review for 10.1186/s12876-018-0857-0 (2018)

Reviewer ’s report  
Title: Tolvaptan treatment improves survival of cirrhotic patients with ascites and hyponatremia  
 
Version: 1 Date: 15 May 2018  
 
Reviewer: Nobuyuki Toshikuni  
 
Reviewer's report:  
In this study, the authors examined whether tolvaptan can prolong survival of patients with 
cirrhosis and hyponatremia. The reviewer has the following comments.  
 
1. Regarding the assignment of patients, there we re differences in some variables. These 
differences were somewhat unexpected because the study design was a randomized controlled 
trial. In particular, a difference in mean age is an issue because age is a very important factor 
capable of influencing survi val prognosis.  
 
2. How do the authors explain the reasons why s short period of tolvaptan administration could 
maintain good conditions of the enrolled patients?  
 
3. In the statistical analysis section, the authors should describe the method for assessing survival 
differences, e.g. the log -rank test. Did the authors use a multicomparison method in Figure 2B?  
 
4. There were some word errors. Please check the text.  
 
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.  
Unable to assess  
Are you able to assess any statistics in the manus cript or would you recommend an 
additional statistical review?  
If an addition al 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, fees, funding, or salary from an  
organisation that may in any way ga in 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 
financially from the publication of this manuscript, either now or in the f uture?  
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 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 a ll 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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to the editors, which will n ot be published.  
 
I agree to the open peer review policy of the journal