Review for 10.1186/s12876-019-0965-5 (2019)

Reviewer’s report
Title: Impact of Primary Colorectal Cancer Location on the KRAS Status and its Prognostic Value
Version: 1 Date: 30 Oct 2018
Reviewer: Desmond Yip
Reviewer's report:
Some language and grammatical corrections required
Suggest that a CONSORT diagram be included to indicate how many papers the search found and how  
these fitted into each of the analyses the number of excluded studies and reasons for exclusion.
Figure 1 and 3, 4 need labelling of the x axis especially what each side of the graph represents.
Combine survival analysis of the patients in the paper was done with inclusion of 5 papers that had  
survival data. Need some details on the patient population ie early stage cancers or included metastatic  
cases.Did patients in these series have access to anti EGFR therapies in the palliative setting?
Charlton paper listed in table 3 does not have mutational status. Was this a subset of the Chalton dataset  
used in the analysis in Figure 4
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.
Yes
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:
Needs some language corrections before being published
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