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: 0 Date: 22 Mar 2019
Reviewer: Kathrin Gschwendtner
Reviewer's report:
In this study 467 breast cancer patients were asked via an Internet-survey about their regret regarding  
the decision making process within their cancer treatment. Older women, working part-time and made  
their decision collaboratively with their doctors, having a BCT were less likely to experience regret.  
The most regrettable experience were regarding the information seeking process (gathering information  
and  not  consulting  others).  For  younger  women  information  about  fertility and  sex  life  is  more  
important than for older women.
This study contributes essentially to description of the status quo of regret in cancer treatment in breast  
cancer patients. The method and analysis of the study are well-designed.
I have following suggestions for the improvement of this study/paper:
Background:
Page 4, line 11. Please, start a new sentences after QOL [2,3]. "While" is confusing in this context.
Page 4, line 18-20: Please provide the essential results of the mentioned studies.
Page 5, line 4: Maybe there are no studies for Japan but their might be studies in other countries. What  
do they find? It might be helpful to legitimate your choice of predictors in the regression analysis.
Page 5: What are your hypotheses for this study/ what do you expect?
Methods:
Page 6, line 5: How did you develop these items? Why is there no option about regretting the decision  
about treatment options?
Page 6, line 19: considered (not consiered)
Page 7, line 7: Please mention all predictors and the dependent variable in detail.
Discussion:
Please stay closer to the results and do not over-interpret your results.
Page 9, line 11: What does "gathering information" mean?
Page 9, line 19: decision-making regret instead of decision-making (?)
Page 10, line 5-7: I do not understand the message of this sentence. Please rewrite.
Page 10, line 12: Missing space after [7].
Page 10, line 15-17: I would not follow this argumentation about more treatment options. Patients with  
a BCT have the less invasive surgery not struggling with major damage in their body image, therefore a  
total mastectomy might lead to more distress and regret. 
Page 11, line 6: Why should women in part-time, who have less regret, have more problems to continue  
work after treatment? In your argumentation they should have rather more regret, because they cannot  
continue  to  work  like  before  treatment.  You  surveyed  the  job  status  after  treatment  so  the  
considerations about work under therapy is a different topic.
Page 13, line 17: I guess it is not so much the sociocultural background but age.
Page 14, line 1- 7: Please shorten and condense.
Page 15, line 18: "Regret about the decision making process" vs. "decision regret"- that is a very  
interesting point- please expand on it. May be it could be useful to integrate this difference also in the  
background.
Tables:
Table 1: For age provide mean and standard deviation.
Table 2: Highlight significant results.
Table 4: What does "(years)" mean?
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.
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
Declaration of competing interests
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