Reviewer’s report
Title: Correlates of regret with treatment decision-making among Japanese women with breast cancer:  
Results of an Internet-based cross-sectional survey
Version: 1 Date: 24 May 2019
Reviewer: Ann Hamilton
Reviewer's report:
I appreciate the revisions that have been made in response to my previous comments.
However I have some concerns about the interpretation of the results that was made in the discussion  
and I have some revisions requested for the tables.
Specifically,  for  Table  3,  the  direction  of  the  regrettable  experiences  should  be  stated,  e.g.  Not  
gathering information, Not connecting with others, not sure what was meant choosing a hospital, Not  
taking the time to consider options and Not building trusting relationships with doctors.
Table 4: add 'by age at diagnosis' to the end of the title.
Discussion:
First two paragraphs are highly repetitious. I would delete the sentence that starts with ' For women  
who had a TM. . . .' and replace it with the sentence in the next paragraph that starts 'Multiple logistic  
regression analyses revealed . . . .'.
My largest concern was with the attempt to explain why this paper found that for those with TM only  
when they made decisions collaboratively did they experience lower regret and that the congruence of  
their decision with their preference for decision making was not a factor. Other papers had found  
congruence to be more important. This difference was attributed to the fact that the previous study  
included more higher stage cases and this one is based on stages 0-II only.  Then later it is stated that  
'our results provide insight to the question that collaborative decision making is more important for  
those undergoing TM--But this seems contradictory to the explanation that the difference between the  
studies was based on the stage distribution. Maybe it should be stated that this insight is only apparent  
among those with TM who were diagnosed at a lower stage. A distribution by stage for those with TM  
was not provided in this paper. On the top of page 12, it was stated that some patients with TM may  
have unwillingly had this surgery because of their advanced stage distribution--but aren't they all stage  
0-II?  On page 15 discussion is made about discussion of fertility concerns. I think this would depend  
on the age distribution of the patients to truly understand if there is a gap in provision of this service.
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.
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:
Acceptable
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