Review for 10.1186/s12876-019-1120-z (2019)

Reviewer’s report
Title: A newly noninvasive model for prediction of non-alcoholic fatty liver disease: utility of
serum prolactin levels
Version: 0 Date: 30 Jun 2019
Reviewer: Zhou Zhou
Reviewer's report:
The current project "A newly noninvasive model for prediction of non-alcoholic fatty liver disease: 
utility of serum prolactin levels" composes a new formula in the diagnosis of NAFLD. The research is 
well designed. Here are some major concerns:
1. The authors should provide all the p values of independently associate factors in Table 2 after
regression analysis.
2. How are the constants of constructed formula made? Is it from regression analysis? How are 
the cutoff threshold determined? Is it from a preferable sensitivity/specificity?
3. The authors should recalculate Table 3.
4.  In comparison to the conventional LFI, the current formula has higher sensitivity but lower 
specificity. The authors should discuss both of them and provide possible solution for 
specificity.
5. The authors can compare the calculation results of current formula and LFI in another table 
so that the readers can have better understanding of the current research.
6. Because PRL is the new factor in this research, the authors can also make another formula 
without PRL and compare it with the current one. This comparison can address the renovation 
of the current study.
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 the 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 recommend additional statistical review
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 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, 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 under 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 published.
I agree to the open peer review policy of the journal