Review for 10.1186/s12876-019-1141-7 (2019)

Reviewer ’s report  
 
Title: Single -session esophagogastroduodenoscopy and endoscopic ultrasound using a forward -
viewing radial scan ultrasonic endoscope  
 
Version: 0 Date: 15 Sep 2019  
 
Reviewer: Kousuk e Minaga  
 
Reviewer's report:  
 
This manuscript reports the feasibility and safety of single -session esophagogastroduodenoscopy 
and endoscopic ultrasound in the detection of uppergastrointestinal and pancreaticobiliary 
diseases using a forward -viewing radial scan ultrasonic endoscope. Th e primary endpoint was 
the safety of the procedures. In this study, as an adverse event, intraoperative hypotension 
occurred in one patient. No other adverse events were noted; therefore, the authors concluded the 
simultaneous performance of EGD and EUS us ing a new ultrasonic endoscope is tolerable and 
safe for upper -gastrointestinal and pancreaticobiliary screening. The topic of this manuscript was 
interesting and the manuscript was well written. Shortcomings of this study is that there is no 
comparison gr oup, so that the diagnostic ability of the new scope and the conventional scope 
cannot be compared, and the number of registered patients is small.  
1. In this study, there are many patients who refused to participate, and only 148 patients 
were registered in the end. Is there any reason to end the registration in December 2018 without 
continuing registration? Did you set the target number of cases before planning this study?  
2. Please clarify the design of this study. Is "retrospective study using a prospectively 
collected data" correct design?  
3. The diagnostic ability of EGD using a forward -viewing radial scan ultrasonic 
endoscope can be compared with conventional endoscopes at  the time of follow up. How about 
that?  
4. The authors mentioned that this study aimed to evaluate the safety and efficacy of 
single -session esophagogastroduodenoscopy and endoscopic ultrasound…; however it seems 
difficult to evaluate efficacy with this me thod. Isn't feasibility correct ?  
 
 
 
 
 
 
 
 
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 contr ols 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 recommen d 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:  
 
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  
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  
financi ally 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 organiz ation 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 th e 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.  
 
I agree to the open peer review policy of the journal. I understand that my name will  be included  
on my report to the authors and, if the manuscript is accepted for publication, my named report  
including any attachments I upload will be posted on the website along with the authors'  
responses. I agree for my report to be made available unde r an Open Access Creative Commons  
CC-BY license ( http://creativecommons.org/licenses/by/4.0/ ). I understand that any comments  
which I do not wish to be included in my named report can be included as confidential comments  
to the editors, which will not be p ublished.  
 
I agree to the open peer review policy of the journal