Reviewer’s report
Title: 
Is the use of contraceptives associated with periodontal diseases? A
systematic review and meta-analyses
Version: 
1 
Date: 
23 Apr 2020
Reviewer's report:
Dear authors,
thanks for having provided this manuscript that tries to investigate the
relationship between the use of contraceptives and the periodontal status.
Even if the topic could be of interest and fall within the scope of the journal
unfortunately the work suffers from too methodological flaws to be accepted for
publication.
Here you can find a list of major issues:
METHODS
1. You attached as supplementary material a wrong/shorter version of the
PRISMA. The whole version is composed by 27 domains. 
2. Manual search is missing.
3. Date of last search is not provided.
4. Line 115: it is not specified if the reviewers worked in duplicate (as it should
be).
6. Line 129: you decided to use the "guidelines proposed by Fowkes and Fulton"
for the quality and risk of bias assessment of all included studies, no matter the
study design. I suggest to change and use scales calibrated on the specific study
design (e.g. Newcastle-Ottawa scale) as in the present form the comprehension
and readability is really affected.
7. Line 144: the concept is not clear.
8. Line 150-152: this lines are to be moved in results.
9. Line 159-162: very hard to understand, please rephrase.
RESULTS
1. Line 171-172: what is written does not correspond to the figure, please check.
2. Line 182-183: Apparently nonsense: route of administration or contraceptive
type?
3. Line 189-197: Editing to be revised as this period is duplicate.
4. Line 223: how did you face the problem of a so high heterogeneity? Here you
should write about the random-effect model to be used.
5. Line 228: here it should be reported that meta-analysis was not significant
giving details about the reasons
6. Table 4 is very hard to understands: English is not correct. I suggest to draw
inspiration from other reviews for a better table presentation.
DISCUSSION
1. Line 242-244: Very hard to understand, please rephrase.
2. This point and the subsequent one can be considered the worst fault of this
review and the main reasons for rejection: in line 245-246 you declare that "no
restrictions for a type of hormonal contraceptives" (cit.) have been carried out.
Needless to say that it is a huge selection bias since, as you clearly state in
introduction, different pharmacological molecules are used as contraceptives
with, probably, different systemic (and obviously local) effects.
3. Same selection bias as above this time regarding the posology (as stated by
you in line 284-285). No standardization is done.
4. Line 251-264: Out of topic since it is a merely description of what periodontal
diseases and systematic reviews (with some improprieties) are. It should be
moved in introduction.
5. Line 309-310: The results of your meta-analysis about PD does not indicate
that a lower rate of inflammation is present in women taking contraceptives; it
simply demonstrate the absence of difference between groups (taking and non-
taking).
6. Limitations are missing.
7. External validity is missing.
GENERAL COMMENTS
1. English needs to be strongly revised by a native speaker. There an
embarrassing quantity of typos, grammar errors, spelling errors and often words
in Portuguese. Please be sure that your next submission will be done after a very
deep language revision.
2. The terms PB and PD are used interchangeably even if the accepted acronym
for Probing Depth should be only PD.
Regards
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.
No
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 am able to assess the statistics
Quality of written English
Please indicate the quality of language in the manuscript:
Not suitable for publication unless extensively edited
Declaration of competing interests
Please complete a declaration of competing interests, considering the following
questions:
1
. 
Have you in the past five years received reimbursements, fees, funding, or
salary from an organisation that may in any way gain or lose financially
from the publication of this manuscript, either now or in the future?
2
. 
Do you hold any stocks or shares in an organisation that may in any way
gain or lose financially from the publication of this manuscript, either now
or in the future?
3
. 
Do you hold or are you currently applying for any patents relating to the
content of the manuscript?
4
. 
Have you received reimbursements, fees, funding, or salary from an
organization that holds or has applied for patents relating to the content of
the manuscript?
5
. 
Do you have any other financial competing interests?
6
. 
Do you have any non-financial competing interests in relation to this
paper?
If you can answer no to all of the above, write 'I declare that I have no competing
interests' below. If your reply is yes to any, please give details below.
I declare that I have no competing interests
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