Reviewer’s report
Title: 
Is the use of contraceptives associated with periodontal diseases? A
systematic review and meta-analyses
Version: 
2 
Date: 
19 Aug 2020
Reviewer's report:
Dear authors,
I received again this manuscript even if, already from the first round of revision,
it was clear that all the methodological flaws that emerged could have not been
solved through revision.
I confirm my opinion of rejection.
Regards
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Is the study design appropriate to answer the research question (including the use
of appropriate controls), and are the conclusions supported by the evidence
presented?
No
Are the methods sufficiently described to allow the study to be repeated?
No
Is the use of statistics and treatment of uncertainties appropriate?
No
Is the presentation of the work clear?
No
Are the images in this manuscript (including electrophoretic gels and blots) free
from apparent manipulation?
Yes