Review for 10.1186/s12876-019-1057-2 (2019)

Reviewer ’s report  
 
Title: Current Diagnosis and Management of Crohn ’s Disease in China: Results from a 
Multicenter Prospective Disease Registry  
 
Version: 0 Date: 22 Apr 2019  
 
Reviewer: Siew Ng 
 
Reviewer's report:  
 
Yue Li et al. described the epide miology and clinical characteristics of around 500 Crohn's 
disease patients in 14 tertiary centers in China.  It represents one of the largest registries in 
China. Although population based cohorts are much desired the challenges in conducting such 
studies  in China highlights the importance of multi -center cohorts. So these data provide some 
value to our understanding of disease characteristics and management of IBD in an area of 
emerging disease incidence. I agree that there may be selection bias from tert iary centers but the 
data are reflection of real life cohorts.  
 
A few comments for the authors:  
 
1. This registry included nearly 500 CD patients from different parts of China. Recent data 
showing that the incidence of CD increased rapidly along the coasta l areas in China due 
to rapid urbanization. Did the authors look in to the difference in incidence and disease 
behavior between different regions in China?  
2. It was mentioned in table 1 that 20.2% of patients had penetrating behavior (B3). 
However, in sup plement table 6, there were no patients having B3 behavior. I am 
confused about this part.  
3. It was mentioned the commonest operations in this cohort was "other surgeries for CD". 
Can the authors elaborate on what are these?  
4. It was mentioned that pati ents with history of liver diseases were 7.9 times more likely to 
have surgery for CD and patients with family History of DM were 8.8 times more likely 
to have surgery for CD. Any explanation for this?  
5. 28.8% of the cases have perianal involvement. Prese nce of perianal involvement usually 
signify poorer disease prognosis. So in this cohort, do patients with perianal CD have 
higher chance of requiring surgery?  
6. Some grammatical mistakes. For example, on page 13, row 308, it should be "According 
to a rep ort" instead of "According report".  
 
Are the methods appropri ate 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 in your comments to the authors.  
 
Unable to assess  
 
Are the conclusions d rawn 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 manus cript 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 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 interests, considering the following questions:  
1. Have you in t he past five years received reimbursements, f ees, funding, or salary from an 
organisation that may in any way gain 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 organisat ion t hat 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 reimbursemen ts, 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 t his 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.  
 
Nil 
 
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