Reviewer ’s report  
 
Title: Motivations for contralateral prophylactic mastectomy as a function of socioeconomic 
status  
 
Version: 0 Date: 13 Oct 2016  
 
Reviewer: Alejandra De Mendoza  
 
Reviewer's report:  
 
The manuscript is clear and well written and it examines the association between socio -
demographic characteristics and d isease severity and motivations for contralateral prophylactic 
mastectomy (CPM) uptake in breast cancer patients who underwent CPM.  The paper addresses 
an important topic and provides further insight into specific motivations to undergo CPM even if 
CPM co ntradicts medical recommendations. Findings from this study can inform targeted 
communication strategies. However, the manuscript has several limitations that could be 
strengthened with the following suggestions:  
 
Material and Methods:  
Questionnaire devel opment: The manuscripts mentions that drafts of the questionnaire where 
piloted in small focus groups that included survivors. Please, provide more detail on how the 
questionnaire was piloted: how many focus groups, how many women in each focus group, how 
many were survivors, and the way the items were piloted and refined.  
 
Data collection:  
1. Recruitment of ethnic minorities was low, despite the fact that one of the sites had equal 
representation of Black and White patients. This should be mentioned as a  limitation of the 
study as well as potential strategies that can enhance the representation of ethnic minorities 
in future studies.   
2. More information is needed about the process of conducting the surveys: There is no 
information about informed consent  or who and how the survey was administered  
 
Study population  
1. The paper mentions that 4 patients self -identified as BRCA1/2 positive and were excluded 
from the analysis as CPM would be recommended. If there wasn't a question for all patients 
about thei r BRCA1/2 mutation carrier status, it is possible that other patients were mutation 
carriers and should have been excluded, especially given that the average age of diagnosis 
was 50 years old.  This is an important flaw that needs to be addressed in the li mitations of 
the study.    
2. Please provide more information on how variables were dichotomized. For example, the 
mean age was 50, why was age dichotomized at 46?  
 
Methods  
1. Please, add a section on statistical analysis in the methods section  
2. Table 2 is referenced in the text but it is missing from the paper  
3. Line 47, page 9, take out the commas before and after "univariate"  
4. The title in Table 4 should also include disease severity  
 
Discussion  
1. The discussion can be strengthened by a dding some discussion on research on risk 
perception and biases and how communication or education materials could be designed to 
avoid the overestimation of small risks.   
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.  
 
Unable to assess  
 
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 recommend additional statistical review  
 
Quality of written English  
Please indicate the quality of language in the m anuscript:  
 
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 th at 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, ei ther 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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