Reviewer ’s report  
 
Title: Comparative Efficacy of Statins, Metformin, S pironolactone and Combined Oral 
Contraceptives in Reducing Testosterone Levels in Women wi th Polycystic Ovary Syndrome: A 
network meta -analysis of randomized clinical trials.  
 
Version: 0 Date: 14 Jan 2020  
 
Reviewe r: Satoko Osuka  
 
Reviewer's report:  
 
The authors conducted network meta -analysis (NMA) to evaluate the effectiveness of statins 
alone or in combination with metformin in treating patients with PCOS.  
 
They concluded that moderate to high intensity statins alone is ef fective than other management 
strategies in reducing the total testosterone levels in PCOS patients.  
 
The concept of this manuscript is very important and the result is informative for clinicians and 
researches who are working in PCOS fields.  
 
If the author s can improve some points, this paper will provide much more impact and 
significance.  
 
1. The authors should include the word 'testosterone' in the title. This title may mislead readers 
into the impression that the outcome of this analysis is improving all  symptoms of PCOS, 
including ovulation disorder, infertility, insulin resistance, etc.  
 
2. Assessments of inconsistency should be performed in a NMA. PRISMA NMA Checklist 
includes assessment and exploration for inconsistency. Please describe the statistica l methods 
used to evaluate the agreement of direct and indirect evidence in the network, and describe the 
results from the investigation of inconsistency.  
 
Quality of written English  
Please indicate the quality of language in the  manuscript:  
 
Acceptable  
 
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, f ees, funding, or salary 
from an organisation that may in any way gain or lose financial ly 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 m anuscript, 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 ha ve 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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