Review for 10.1186/s12876-016-0417-4 (2016)

Reviewer’s report  
Title: i-Scan detection of minimal change esophagitis in dyspeptic patients with or without 
Gastroesophageal Reflux disease.  
 
Version: 0 Date:  13 Sep 2015  
 
Reviewer:  Johannes  Rey 
Reviewer’s report:  
To the authors  
 
This is a single center cohort study at a tertiary center in Thailand. 144 patients were enrolled to 
defined the efficacy of iScan endoscopy (SE) in minimal change esophagitis (MCE). 144 patients 
were included. All patients had done a 24 hour ph monitoring and were divided into two groups 
(A, B) a nd in forty normal volunteers as control group. The positive predictive value of SE was 
reported to be 36,54%. The authors concluded that SE detected more MCE in GERD than in 
non-GERD patients, and in controls. However, for its publication, there are some important 
points to be clarified as indicated below:  
 
Major Points  
 
1. In the study protocol the authors reported that the distal esophagus was inspected by HD 
and followed by SE. How many MCL did the authors find during the inspection by HD? 
Could this ha ve influence on the results?  
 
2. Were the two endoscopists blinded for later inspection of the images to each other? Why 
did the authors not take the decision during the endoscopy?  
 
3. The positive predictive value (ppv) for SE was reported to be 36,54%. Thi s is in contrast 
to other reports how find a ppv of 100% for iScan (Rey JW et al., 2014), please discuss.  
 
4. What is the accuracy of histology compared against virtual chromoendoscopy? Which 
should be used as the gold standard? Why did the authors did not prove their endoscopic 
finding by biopsy?  
 
5. After many studies using different advanced endoscopic techniques to identify minimal 
changes in the GE junction, at this point I would like to see evidence that there is any 
clinical correlation between minimal  changes and disease behavior or response to anti -
reflux treatment. What is the cost versus benefit here?  
 
6. It was concluded that SE detected more MCE in GERD than in non -GERD patients, and 
in controls. However, do the authors have any data to show from t his study that 
identifying minimal changes altered patients' management?  
 
Minor Points  
 
1. Material and Methods: Exclusion criteria should be displayed in a table. Did the authors 
exclude patients with an axial hernia?  
 
2. Female patients were included twice  more. The authors should discuss this circumstance.  
 
3. The first author of Reference 23. should be revised.  
 
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 spe cify 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.  
 
No 
 
Are you able to assess any statistics in the manuscript o r 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 recommend additional statistical review  
 
Quality of written Engl ish 
Please indicate the quality of language in the manuscript:  
 
Needs some language corrections before being published  
 
Declaration of competing interests  
Please complete a declaration of competing interests, consideri ng 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, e ither now or in the future?  
 
2. Do you hold any stocks or shares in an organis ation that may in any way gain or lose 
financially from the publication of this manuscript, e ither 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 fin ancial competing interests?  
 
6. Do you have any non -financial competing interests  in relation to this pa per? 
 
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  competing interests  
 
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