Reviewer ’s report  
 
Title:  Association of breastfeeding and postmenopausal osteoporosis in Chinese women: a 
community -based retrospective study  
 
Version: 0 Date: 22 May 2019 
 
Reviewer:  Norlia  Abdullah  
 
Reviewer’s report:  
 
This is a good effort. However, being a retrospective  data, recollection bias by the respondents 
would be an important issue. It is unclear how you have recorded  and measured oral 
consumption of Calcium and Vitamin D by the respondents. I am also unclear how you have 
measured parity as the data of this amon gst respondents appear quite uniform and unvaried; yet 
you seem to say that parity appears to have a role in this matter.  
 
Would it be possible to show the questionnaire that you used but translated to English? This for 
us to understand the depth of the que stions asked especially pertaining to dietary intake.  
 
Thank you.2  
 
Are the methods appropriate and well descri bed?  
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.  
 
I am able to assess the statistics  
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
Needs some language corrections before being published  
 
Declaration of competing  interests  
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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 
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3. Do you hold or are you  currently applying for any patents relating to the content of the 
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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?  
 
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below. If your reply is yes to any, please give details below.  
 
I declare that I have no competing interests  
 
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