Review for 10.1186/s12876-020-01212-3 (2020)

Reviewer’ s report
Title: The propionic acid and butyric acid in serum but not in feces are increased in patients with
diarrhea-predominant irritable bowel syndrome
Version: 0Date: 19 Nov 2019
Reviewer: Renato Bocchini
Reviewer's report:
The paper includes a good review of literature data on SCFA role in IBS pathogenesis, but, as
previous papers on this topic, it's of limited clinical value. The reported data are substantially nonconclusive : SCFA role in ibs is not clarified; it could be interesting comparing ibsd results to thoseobtained in diarrheas of different origin; after all, SCFA serum increase in ibs d could be simplyconsequence of diarrhea; difference between hc and ibsd patients could be due to diarrhea and notinvolved in ibsd pathogenesis
Are the methods appropriate and well described?
If not, please specify what is required in your comments to the authors.
YesDoes 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?
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YesAre 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 furtherassessment in your comments to the editors.
Not relevant to this manuscriptQuality of written English
Please indicate the quality of language in the manuscript:
Acceptable
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