Reviewer ’s report  
 
Title: Social networks and quality of life among female breast c ancer patients at Tikur Anbessa 
Specialzed Hospital, Addis Ababa, Ethiopia 2019  
 
Version: 0 Date: 06 Sep 2019  
 
Reviewer: Maria -Victoria Zunzunegui  
 
Reviewer's report:  
This cross -sectional study examines the association between the diversity of social networks and 
quality of life in women with a diagnosis of breast cancer in Ethiopia.  
The study has merit but it cannot be published in its current form due to the following  
methodological flaws:  
a)  More information on the living conditions of these women is needed.  What is their age 
distribution? Why the average age of these patients is so young? Comments are needed since most 
studies of breast cancer in Europe and North A merica report an average age at diagnosis in breast 
cancer patients over 60 years of age and very few patients with breast cancer are younger than 40.   
This huge difference in age could be related to the low life expectancy of women in Ethiopia but 
its so cial consequences are important since these Ethiopian women with breast cancer are in 
reproductive age, having children or with young children at charge, a comparatively rare situation 
in high income countries.  
What are their living arrangements? What is their education distribution? Are they receiving 
financial assistance? Is this hospital a public hospital with universal access? How representative 
are these women of the population of women in their age group in the city of reference?  
 b). Statistical an alyses:  This study could establish an statistical association between the diversity 
of social networks and quality of life, as a continuous score, but statistical analysis is not adequate. 
The dichotomization of quality of life should be avoided since the re is a large loss of information: 
it classifies 92% of women with poor quality of life, as if their QoL were similar.  
Since diversity of social networks is coded in three categories (two dummy variables with a 
reference group of high diversity of social networks) , the coefficients of these dummy variables 
are measures of association of social networks diversity and Quality of life in a simple regression.  
The R2 of this regression ( QoL=a+b * dummy1+ c* dummy2) should be provided. Estimates of 
regression  coefficients b and c  are the measures of association and if different form zero, indicate 
a significant association between. Diversity of networks and QoL.  In a second analysis step, this 
association should be adjusted by covariates adding them as indep endent variables in the model.   
This multiple regression analysis is necessary to assess the independent associations of quality of 
life and diversity of social networks. Results that are presented in this paper did not address the 
aim of the paper. Notic e that social networks is not a dependent variable but the exposure of 
interest.  
c) the sample size determination section should be removed from this paper. The formula used is 
adequate to estimate a proportion with a given precision but it does not addre ss the problem of 
estimating the difference in scores of quality of life in groups defined by  a categorical variable.  
 
Minor points:  
The quality of the English language should be revised.  
Tables should be clearer: A descriptive table is needed. A bivaria te analyses using as outcome the 
quality of life score and a multiple linear regression adjusting the association by all covariates.  
 
 
Are the methods appropriate and well described?  
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 y our 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 qua lity of language in the manuscript:  
 
Not suitable for publication unless extensively edited  
 
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 salar y from an 
organisation that may in any way gain or lose financially from the publication of this  
manuscript, either now or in the future?  
 
1. Do you hold any stocks or shares in an organisation t hat may in any way gain or lose 
financially from the publicati on of this manuscript, either now or in the future?  
 
2. Do you hold or are you currently applying for any patents  relating to the content of the 
manuscript?  
 
3. 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?  
 
4. Do you have any other financial competing interests?  
 
5. 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 decla re 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  
 
I agree to the open peer review policy of the journal. I understan d that my name will be included 
on my rep ort to the authors and, if the manuscript is accepted f or publication, my named report 
including any attachments I upload will be posted on the website along with the authors' 
responses. I agree for my report to be made available under an Open Access Creative Commons 
CC-BY license ( http://creativecommons.org/licenses/by/4.0/ ). I understand that any comments 
which I do not wish to be included in my named report can be included as  confidential comments 
to the editors, which will not be published.  
 
I agree to the open peer review policy of the journal