Review for 10.1186/s12876-019-1105-y (2019)

Reviewer’s report
Title:  Stress ulcer prophylaxis with proton pump inhibitors or histamine 2 receptor antagonists in
critically ill adults - A meta-analysis of randomized controlled trials with trial sequential analysis.
Version: 0 Date: 01 Oct 2019
Reviewer: Angelo Zullo
Reviewer's report:
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This  meta-analysis of randomized controlled studies aimed to assess the role of therapy with PPI or
H2-antagonist for stress ulcers prophylaxis (SUP). In detail, data of 29 studies (4 at low risk of biases)
were evaluated.  Basically, data found that SUP has benefits on the overt GI bleeding - but not
clinically relevant bleeding - in critically ill patients who did not receive enteral nutrition. The Authors
cautelatively concluded there is need of more evidences. 
The analysis is comprehensive, data was well analyzed, and interpretation is correct. Therefore, I have
not major criticisms to do. As a comment, I would suggest that PPI dose, route of administration, and
therapy duration are highly different among trials, so that it could be a mattern for concern. In other
words, a certain therapy could be more effective than another so that considering all therapy regimens
as "PPI therapy" could be misleading. These considerations could be briefly discussed.
Are the methods appropriate and well described?
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Yes
Does the work include the necessary controls?
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Yes
Are the conclusions drawn adequately supported by the data shown?
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Yes
Are you able to assess any statistics in the manuscript or would you recommend an additional
statistical review?
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assessment in your comments to the editors.
I am able to assess the statistics
Quality of written English
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Acceptable
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