Review for 10.1186/s12876-016-0565-6 (2017)

Reviewer ’s report  
 
Title: A significant cancer burden and high mortality  of Intrahepatic Cholangiocarcinoma in 
Thailand: a nationwide database study.  
 
Version: 1 Date: 25 Oct 2016  
 
Reviewer: Teng -Yu Lee  
 
Reviewer's report:  
 
Major concerns:  
1. Study novelty: The high mortality rate and high prevalence rate of ICC in Thailand have 
been known, and no novel information could be provided for international  journal readers 
from this study.  
2. Limitations of the Nationwide Hospital Admission Database: This database was not a truly 
nationwide study, and most private medical systems might not be included. Has the database 
been validated?     
3. Inadequate epidem iological methodology: The authors still reported ICC burden based on 
patients with GI diseases in the manuscript, and a better way to draw a concrete picture is 
suggested. The manuscript should be completely revised.   
4. Risk factors of CCA: No data of CC A risk factors was provided. The manuscript should be 
completely revised only based on their findings.  
5. No data of tumor staging: The value of this study was largely reduced.  
6. Multivariable analysis for overall mortality: The authors further reported th at ICC patients 
who had LOS <7 days had significantly lower frequency of comorbidities, but factors related 
to ICC was not well analyzed.  
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.  
 
No 
 
Are the conclusions drawn 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  
Please complete a declaration of competing inte rests, 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 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 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 co mpeting interests.  
 
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