Reviewer ’s report  
 
Title: Evaluating the role of race and medication in protection of uterine fibroids by type 2 
diabetes exposure  
 
Version: 0 Date: 14 Feb 2017  
 
Reviewer: Kui Zhang  
 
Reviewer's report:  
 
Review for BMC Women's Health  
Manuscript Number: BMWH -D-16-00090  
Title: Evaluating the role of race and medication in protection of uterine fibroids by type 2 
diabetes exposure  
Authors: Edwards et al.  
 
Comments.  
In this manuscript, the authors studied the association of T2d and UF risks. They used 3879 
subjects with UF outcomes (608 cases and 3181 controls) and T2D exposures (714 with diabetes 
and 3075 without diabetes). These sa mples were extracted from the Synthetic Derivative (SD) 
database located at Vanderbilt University, Nashville, TN. The authors used the logistic 
regression analysis with the UF outcome as the response, the T2D status as the independent 
variable, and with or  without adjustment of race, age. They also performed the stratified analysis 
according to the race and the T2D medication. They found a protective association between 
diabetes presence and UF risk and is further modified by race, which confirmed the concl usions 
from previous studies. The strengths of their studies include a large number of case and controls 
and the appropriate statistical analysis. I only have some minor comments.  
 
Comments.  
The samples were extracted from the database and the method used  to extract the samples were 
used before and published. However, there was no description or discussion about the reliability 
and accuracy of these samples in this manuscript.  
 Page 2, Line 37, "We identified 3,789 subjects with UF outcomes (608 UF cases and 3,075 
controls)", here 3075 should be 3181 according to Table 1.  
Page 2, Line 43, "interaction between T2D exposure and race (likelihood ratio P < 0.10)", it 
would be helpful if the authors can provide the exact p -value here.  
Page 8, Line, "The effec t of T2D exposure on UFs was protective for all adjusted analyses 
evaluating the different types of medications." I do not think this is true. For Thiazolidinedione - 
the 95% CI of adjusted OR is from 0.56 to 1.48 (Table 3).  
Tables 2 and 3, it would be ve ry helpful if the authors can provide p -values for all odd ratios.  
Page 19, Table 1. This table is very hard to understand and there were quite a few errors. (1) The 
percentages in this table are not informative. For example, 59% of 608 Fibroid cases are 
European Americans meaning about 359 Fibroid cases are European Americans. However, this 
is not true since the number of samples with the race information is 3547 not 3789 according to 
Table 1. So there were some cases without race information but we do no t know how many of 
cases without the race information. (2) What are the mean and SD of BMI? (3) There are 2496 
samples with BMI while the summation of number of samples across all BMI groups is much 
less than this number. (4) The sum of treatment percentag es is much less than 100%. (5) There 
are 308 samples with insulin treatment in Table 1 while the number becomes 3,481 in Table 3.  
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
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 r ecommend 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:  
 
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, 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  
financi ally 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 organiz ation 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 tha t I have no competing interests  
 
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