Review for 10.1186/s12876-020-1173-z (2020)

Reviewer’s report
Title: Prevention and management of diarrhea associated with naldemedine among patients
receiving opioids: a retrospective cohort study
Version: 0 Date: 21 Apr 2019
Reviewer: Ivano Biviano
Reviewer's report:
The present paper addresses the important  issue of management side effects of opioids therapy in "real
life" experience , allowing a direct application on clinical practice. 
However, some important issues need to be clarified: 
1. Definition of diarrhea utilized in the study should be explained
2. The results are not very clear (description of population subgrouping, entity of diarrhea)
3. Numerosity between the two groups is unbalanced, data on number of evacuations should
expressed as median and statistic revised
4. Figures should be better explained  (unit of measure/patients )
5. Figure 3 is unclear, standard deviation is not shown 
Typos
1. pag 8 "suivival"
2. Abbreviations should be explained  ("PAMORA" "peripherally-acting mu-opioid receptor
antagonists")
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.
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.
Not relevant to this manuscript
Quality of written English
Please indicate the quality of language in the manuscript:
Acceptable
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