Review for 10.1186/s12876-020-01431-8 (2020)

Reviewer’ s report
Title: Metastatic Pancreatic Adenocarcinomas Could be Classified into M1a and M1b Category
by the Number of Metastatic Organs
Version: 1Date: 22 Jul 2020
Reviewer's report:
I think the authors have adequately addressed most issues raised during the review. As one more
minor point, I would recommend specifying in the manuscript text that Schoenfeld residuals wereused for "verifying the proportional of hazards assumption" instead of "verifying the factorsassociated with prognosis".
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(default)
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?
YesAre the methods sufficiently described to allow the study to be repeated?
Yes
Is the use of statistics and treatment of uncertainties appropriate?YesIs the presentation of the work clear?YesAre the images in this manuscript (including electrophoretic gels and blots) free from apparent
manipulation?
Yes