Review for 10.1186/s12876-018-0799-6 (2018)

Reviewer ’s report  
 
Title:  Length of Barrett's Segment Predicts Failure of Eradication in Radiofrequency Ablation 
for Barrett's Esophagus: A Retrospective Cohort Study  
 
Version: 0 Date: 21 Feb 2018 
 
Reviewer:  Zhiqin  Wong  
 
Reviewer’s report:  
 
There are several limitations in this study.  
 
1. This is a retrospective study  
 
2. Please relook at references as stated below:  
 
Page 5 Line -43 Reference jump to 28 (after ref 16), not following sequence  
 
Page 6 line 4 - reference 22  
 
Page 6 Line 9 - reference 21  
 
Page 6 line 7 - protocol for ablation to be mentioned  
 
Page 8 line 21 -22 - tobacco not co -morbidities. Rather a risk factor  
 
 
Methods:  
 
How was endoscopic examination being standardized in this study?  
 
How was the choice/type of ablation selected?  
 
Page 5 - Line 12 -16 - Was biopsies obtained after every third RFA sessions? As the range of 
RFA therapies is 2 -10 times.  
 
 
Results :  
 
Please writ e it in a more organized way for first paragraph (Page  7 line 6 -36) 
 
For example to start of with demographic, then clinical / endoscopy features, follow by treatment 
ad outcome.  
 
Page 7 -  
Please decide on mean / median for length of BE (line 16 and line 24 ) 
 
Please provide n for demographic details in result demographic details of this group of patients - 
age, gender, BMI (overweight or obese, please standardized terminology used )  
 
Line 12 - please change esophageal cancer to esophageal adenocarcinoma  
 
Any history of alcohol consumption  
 
Was there any complications observed for all 107 patients?  
 
The range of RFA is huge (between 2 -10), and more than half (54.3%) of patients did not 
achieve complete eradication despite > 3 treatments. What was the reason  for the huge range in 
number of treatments received? Was choice of ablation a contributing cause?  
 
Was there any difference in achieving complete ablation between circumferential and focal 
ablation? Does it affect the number of RFA treatments in this study?  
 
Do the patients who developed esophageal adenocarcinoma observed the same independent 
predictors  of failure in both CE -IM and CE -D? 
 
 
Discussion:  
 
Page 8 line 24 -31, please rephrase, the current phrasing makes comprehension difficult.  
 
Line 46 -53 - please cite reference  
 
 
Attachments:  
 
Table 1 - EMR and RFA should be classify under treatments recei ved and not endoscopic 
characteristics  
 
The English language is clear however please do check some grammatical error.  
 
I commend the author for their extensive data set complied over many years and the manuscript 
is written clearly in unambiguous langua ge. The major weakness will be a retrospective study 
and the methods and analysis of results should be improve (as mentioned above) before 
acceptance.  
 
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.  
 
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 i ndicate 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, 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 fro m 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 decl are that i have no competing interests.  
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