Review for 10.1186/s12876-016-0527-z (2016)

Reviewer ’s report  
Title:  Increasing Mortality in the United States from Cholan giocarcinoma: an Analysis of the 
National Center for Health Statistics Database  
 
Version:  0 Date:  27 Feb 2016  
 
Reviewer:  Jessica Yu  
 
Reviewer's report:  
This manuscript highlights the increasing mortality rate of cholangiocarcinoma in the US, broken 
down based on age, race and gender. It would be interesting to look at other risk factors that may 
be linked with cholangiocarcinoma and how they contribute to their findings. For example, the 
authors point to PSC as a potential reason why mortality may be increased in males, it would be 
interesting to include in the results a breakdown of rates of PSC and other risk factors such as 
parasitic infections, other biliary infections etc.  It is also unclear why hispanic origin was 
analyzed specifically.  
 
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 required i n your comments to the authors.  
Unable to assess  
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  
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 recommend additio nal statistical review  
Quality of written English  
Please indicate the qu ality of language in the manuscript:  
Needs some language corrections before being published  
Declaration of competing interests  
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