Review for 10.1186/s12876-018-0847-2 (2018)

Reviewer’s report
Title: Efficacy and safety of tenofovir in preventing mother-to-infant transmission of hepatitis B virus:  
a meta-analysis based on 6 studies from China and 3 studies from other countries
Version: 0 Date: 25 Mar 2018
Reviewer: Alessandra Mangia
Reviewer's report:
This is an interesting meta-analysis on the impact of tenofovir in reducing the risk of  vertical HBV  
trasmission.  Unfortunately, due to relevant differences across the studies, results of this meat-analysis  
cannot be generalized. The heterogeneity represents an important limitation of this study. As stated in  
the discussion 2/3 of the studies examined were from China, it might be better to include this concept  
in the manuscript title.
The studies  included in this  meta-analysis  were heterogeneous in terms  of treatment comparator.  
Accordingly, it might be  important to specify what drug tenofovir is compared to in every study  
examined in the Results session.  On page 10 line 32: what does "usual medical care" indicate in each  
study?
Another aspect that need to be specified is the timing of the pregnancy when tenofovir treatment was  
started. 
Page 10 line 1. I would say:  phase II clinical trial, rather than protocol
Page 18 For clarity, references of the two different studies quoted here need to be added after the  
control results.
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.
Unable to assess
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
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