Review for 10.1186/s12876-021-01635-6 (2021)

Reviewer’s report
Title: 
Evaluation of serum ATX and LPA as potential diagnostic biomarkers in
patients with pancreatic cancer
Version: 
1 
Date: 
07 Feb 2020
Reviewer's report:
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The manuscript entitled Evaluation of serum ATX and LPA as potential
diagnostic biomarkers in patients with pancreatic cancer present interesting data
concerning new biomarkers for pancreatic cancer (PC).
I find the manuscript interesting and of scientific value. I have some minor
comments.
Overall: The authors sometimes use prognostic marker instead of diagnostic
marker the manuscript. Use diagnostic marker consequently.
Most of the references are quite old although there are more recent studies about
LPA and ATX in pancreatic cancer. Please include some more recent findings
shortly in background and/or discussion.
Methods:
How was patient characteristics like "High sugar diet" and "Alcohol" defined?
How was this information retrieved for the study?
Was Pearson Product Moment used? Where are the results from this analysis
described? In methods, statistical analysis it is written that data should be shown
with median and range in the tables, however, in the tables mean and standard
error of the mean is used. Please change to median and range.
Results: 
page 9, there is an incorrect p value (p<0.642) in the beginning of section
"Biochemical parameters for healthy volunteers, PC patients, and BPD patients"
page 10, If values are given in tables please don´t write the same values in the
text. Table is to prefer. The figure 995.47 (for Ca19-9) is not the same as in the
table- which value is correct?
Discussion:
Page 14 when discussing sensitivity and specificity it must be written out that
this is a post hoc test (since the cut offs are decided from this same population).
Please don´t compare the sensitivity and specificity as in 
the sentence
"Interestingly, LPA had higher
sensitivity (91.74%) but lower specificity (69.4%) for detection of PC from
among the total study population." since this is depending on the cut offs which
you decided. With other cut offs these values will change. It is more correct to
compare the AUC of the ROC curves.
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.
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 recommend additional statistical review
Quality of written English
Please indicate the quality of language in the manuscript:
Acceptable
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