Reviewer’s report
Title: 
Night-shift work duration and breast cancer risk: an updated systematic
review and meta-analysis
Version: 
1 
Date: 
30 Nov 2020
Reviewer's report:
Breast cancer is 
a public health issue since it is the most commonly reported
invasive cancer among women,. Duration of night shift work if identified as a
risk factor of breast cancer can help 
policy makers to regulate or reduce the
chances of contracting the breast cancer.. It was great to see:
i)The assessment of 
publication bias by 
Egger and Begg tests 
and the
minimization of publication bias by a trim and fill method.
ii)Even though 
the study tried to remove some heterogeneity you still indicated
heterogeneity as a i limitation 
of your study.
It will also be interesting to see the following:
1. how you minimized your information bias in the study
i2. What motivated your inclusion criteria? 
Is 24 eligible studies included in the
study enough? why 24?
i3. 
How you minimized analysis bias
4. what is the size of your effect?
i5. Is the effect consistent across studies?
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Is the study design appropriate to answer the research question (including the use
of appropriate controls), and are the conclusions supported by the evidence
presented?
Yes
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Yes
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