Review for 10.1186/s12876-020-01353-5 (2020)

Reviewer ’s report  
 
Title: The comparison of  capnography and epigastric auscultation to assess the accuracy of  
nasogastric tube placement in intensive care unit patients  
 
Version: 0 Date: 01 Feb 2020  
 
Reviewer: Jigeeshu Divatia  
 
Revi ewer's report:  
 
The authors studied whether capnography is superior to epigastric auscultation in detection of 
nasogastric tube placement. They found that the use of the capnography is prefera ble on the 
epigastric  auscultation to confirm the correct insertion of the NG tube.  
 
General comments  
This topic is not new, and has been studied several times, as seen from the reference list  
 
Major issues:  
The sample size calculation is not appropriately  described. In the Methods, the authors say the 
patients were selected by convenience sampling, give an inadequate method of sample size 
calculation.  
 
The methods are not fully described. The authors do not describe the criteria to determine the 
position o f the tube in the tracheobronchial tree, esophagus and oral cavity/pharynx and stomach 
by capnography?  
 
The sensitivity/specificity/acccuracy are determined against what end point? Correct placement 
in the stomach  or incorrect placement in the tracheobro nchial tree?  
 
The Duscussion is not crisp and precise. Resuts of studies and differences from the current study 
are listed but not discussed.  The authors do not distinguish the role of capnogarphy in 
identifying placement in the airway versus the role of  auscultation in identifying placement in the 
stomach.  
 
The Conclusion "It is recommended that more than one method be applied to detect and confirm 
the correct insertion of the NG tube " is not supported by data from the study.  
 
 
 
 
 
 
 
 
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
No 
 
Does the work inclu de 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.  
 
No 
 
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 s tatistics  
 
Quality of written English  
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 inter ests, 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 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 c ontent 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 declare that I have no competing interests  
 
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