Review for 10.1186/s12876-017-0668-8 (2017)

Reviewer ’s report  
 
Title: Portal vein thrombosis in liver ci rrhosis: Incidence, management, and outcome  
 
Version: 0 Date: 03 May 2017  
 
Reviewer: Quirino Lai  
 
Reviewer's report:  
 
Article number BMGE -D-17-00195  
This is an interesting retrospective study from Japan investigatin g the role of danaparoid sodium 
for the treated of PVT in cirrhotic patients. The population is relatively small (n=90) but the 
results are interesting and relatively innovative.  
 
Major comment:  
1) It is not clear how the Authors constructed their multiv ariable model. I think it is correct to 
report that this statistical method has been used into the appropriate "Statistical Analysis" 
section. Moreover, the Authors reported in Table 3 that the model was constructed using 
patient survival as dependent vari able. Such a datum is coherent with the results (age and 
HCC as risk factors and patent PV as protective factor). However it is not clear when the 
patency was defined, as the Authors wrote in the definition of Table 3: "Determinants of 
survival of patients  with liver cirrhosis and portal vein thrombosis after initial treatment, 
repeat treatment and maintenance therapy." Which is the exact timing when they categorized 
the PV patency for doing this analysis?  
In Page 13, line 238 -240, the Authors report the e rroneous sentence that "Multivariate analysis 
identified HCC (HR 3.2426, P=0.0038), age (>65 years; HR2.9734, P=0.0178), and main portal 
vein patency (HR 0.4149, P=0.0205) as significant independent risk factors of PVT". Such a 
statement is in conflict wit h Table 3, in which, more accordingly, the dependent variable is 
patient death and not PVT. In fact, all the patients investigated in the present series had a PVT. 
Moreover, why the Authors did not investigate the risk factors for definitive PVT treatment 
failure? I suppose such an analysis is surely more intriguing respect to the risk factors for patient 
death.  
 
Minor comments:  
1) English style reevaluation is needed.  
 
2) Page 8, lines 131 -134: I suppose the following sentence presents an error: "We divided the 
patients into two groups; patients of the acute type (n=27) developed cirrhosis within one 
month after hepatectomy (16 cases) or splenectomy (11 cases), while tho se of the chronic 
type (n=63) comprised all other patients."  
I suppose the Authors intended that 27 patients developed PVT after hepatectomy or 
splenectomy.  
 
3) Page 26, Table 1. I suggest to report in a more homogeneous way the reported numbers, 
using al ways the same digit of numbers after the comma. Also all the percentages need to be 
reported homogeneously. Such a coherence should be extended to the entire text.  
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
Does the work include the necessary controls?  
If not, please specify which controls are requir ed 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.  
 
Yes 
 
Are you able to assess any statistics in the manuscript or would you recommend an  
addition al 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:  
 
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 rei mbursements, fees, funding, or salary from an  
organisation that may in any way gain or lose financially from the publication of this  
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation that 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 the content o f 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 i nterests.  
 
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