Review for 10.1186/s12876-017-0604-y (2017)

Reviewer ’s report  
 
Title: Real life results in usi ng 5-ASA for maintaining mild to moderate UC patients in Japan, a 
multi -center study; OPTIMUM Study  
 
Version: 0 Date: 12 Dec 2016  
 
Reviewer: Shu Chen Wei  
 
Reviewer's report:  
 
The authors would like to explore the real life experience about using 5 -ASA for maintaining 
remission for mild to moderate UC in Japan. This topic is with p ractical importance. However, 
the current content would be somewhat confusion for the readers. Therefore, please revise the 
manuscript in order to make it clear and more clinical relevant.  
1. Background: please add the information about previous study res ults about the relapse rate of 
UC when with and without 5 -ASA maintenance.  
 
2. Inclusion criteria:  
<1>. since the study was aimed to reveal the relapse rate in mild to moderate UC, probably 
would be more appropriate to exclude those with TNF -a Ab, Tacrolim us. What about steroid? 
The authors did not mention about whether there's concomitant use of steroid or not ? Same as 
about the leukocyte apheresis, which is also a common treatment with the indication for mild to 
moderate UC in Japan.  
<2>. Probably need to analyze when with and without probiotics, since probiotics have been 
reported to have a role in maintaining remission.  
<3>. Need to further analyze when with and without topical treatment.  
<4>. The number of patients could not fit the whole picture of enrollment in Figure 1. (for 
example, 3055+804, not equal to 4013)  
<5>.  Since most of the patients enrolled in this study have long disease duration (108 -110 
months), we can propose that these belonged to a stable group of patients and probably would 
have  a better compliance and better adherence to treatment. We probably would be more 
interesting in those fresh diagnosed group, which indicated to diagnosed within one to two years, 
and see how is the relapse rate.  
3. For those dropped off treatment or foll ow up, these would be the more important group need 
to be understood about why they dropped off the treatment?  Suggest to discuss the reasons.  
 
4. Why female patients tended to be relapse? please discuss.  
 
5. It has been shown that the dosage of 5 -ASA rel ated to mucosal healing. What about the 
situation in this cohort?  The result seemed to be interesting in "no difference in relapse when 
with or without early tapering the dosage of 5 -ASA". Does it mean that we could or even we 
should taper the dosage in o ur real life practice?  
 
6. The topic: probably could adjust to " Real life results in using 5 -ASA for maintaining mild to 
moderate UC patients in Japan, a multi -center study"  
 
7. The figures could be more concise. And please add one to show the relapse abou t with and 
without maintenance treatment.    
Are the methods appropriate and well described?  
If not, please specify wh at 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.  
 
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  
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:  
 
Needs some language corrections before being published  
 
 
Declaration of competing in terests  
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 gain or lose financially from t he publication of this  
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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?  
 
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below.  If your reply is y es to any, please give details below.  
 
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