Review for 10.1186/s12876-017-0667-9 (2017)

Reviewer ’s report  
 
Title: The diagnostic value of pepsin detection in saliva for gastro -esophageal reflux disease: a 
preliminary study from China  
 
Version: 0 Date: 10 Jun 2017  
 
Reviewer: Mohammad Derakhshan  
 
Reviewer's report:  
 
I should congratulate authors for such a comprehensive research and great manuscript.  
In order to give readers a clear pict ure of the methodology of the research I would recommend 
authors a consider more clarifications about control group.As I see in the method section, in 
control selection paragraph they stated that controls were selected from asymptomatic healthy 
volunteers who were recruited from Center of health Examination, the General Hospital of the 
PLA Rocket Force, China, as normal controls.They did not say what was the basis of the 
selection. Then in same paragraph they stated that the protocol was registered as a cli nical trail. 
Please clarfy if control group were a part of a clinical trial for any different study.  
Another issue, which might be related to manuscript rather than original protocol is absence of 
GERD Q score in the control group in Table 1. My assumption  is the control group was assigned 
as control on the basis of symptoms, so normally they should have a symptoms Q score result, so 
why not to put it is the table and show the group was asymptomatic.  
I am happy with rest of the manuscript, and outstanding  discussion and conclusion.  
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 in your comments to the authors.  
 
Unable to assess  
 
Are the conclusions drawn adequately su pported 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 manuscr ipt: 
 
Acceptable  
 
Declaration of competing interests  
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 the publication of this  
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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 t o 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 yes to any, please give details below.  
 
I declare that I have no competing interests.  
 
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