Review for 10.1186/s12876-020-01309-9 (2020)

Reviewer ’s report  
 
Title: Effects of Gastric Sleeve Surgery on the Serum Levels of GH, IGF -1 and IGF -binding  
Protein 2 in Morbidly Obese Patients  
 
Version: 1 Date: 28 Mar 2020  
 
Reviewer: Cyrus Jahansouz  
 
Reviewer's report:  
 
TO DO:  
 
Page 8, lines 20 -24: Please rephrase the final highlighted sen tence -Although one might assume 
that IGF1 sensitivity is improved and perhaps signaling is improved, without a direct 
measurement these are only assumptions.  
 
Page 8, lines 57 -60, last sentence: Please rephrase sentence. Although the elevated levels of TC , 
LDL and HDL may be in part due to increased GH level, there are several potential reasons for 
this, and not just attributable to increased GH levels.  
 
Page 9, lines 44 -47, last sentence: Please rephrase sentence. The role of IGFBP2 is only 
suggested to b e to potentially mediate some of the beneficial effects of the Sleeve Gastrectomy. 
Also please rewrite to make the sentence clearer, but it might be suggested by the sentence that 
IGFBP2 might be responsible for increased GH levels, whereas I think you mea n sleeve 
gastrectomy is responsible for increased GH levels.  
 
In conclusion: please add that GH and IGFBP2 levels may be an endocrine response that may in 
part mediate the beneficial effects. Also please eliminate the last sentence. I think the first 
sentence is an adequate 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 t he authors.  
 
Yes 
 
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 indicate the quality of language in the manuscr ipt: 
 
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, fund ing, 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 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, w rite '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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