Review for 10.1186/1471-230X-14-92 (2014)

Reviewer's report
Title:Increasing late stage and mortality of colorectal cancer demonstrates the
need for screening: a population based study in Ireland, 1994-2010.
Version:2Date:10 March 2014
Reviewer: Antoinette Stroup
Reviewer's report:
Summary: The authors present a well-written paper describing important trends
in incidence, mortality, survival, and staging of colorectal cancer. It is a great
representation of how surveillance data can be use to monitor trends for a
number of key epidemiological measures. The paper also provides a great
backdrop from which to compare and evaluate the future effects of new
screening programs in Ireland.
Discretionary Revisions (which are recommendations for improvement but which
the author can choose to ignore)
1. Background, p. 1, 3rd paragraph: Move “until 2013” to the end of the sentence.
2. Methods, p. 4, 2nd paragraph: Rephrase sentence “…with a date of diagnosis
from 01/01/1994 to 31/12/2010.”
3. Results, p. 6, mortality section: Consider changing “fell over” to “declined
over”.
Minor Essential Revisions (such as missing labels on figures, or the wrong use of
a term, which the author can be trusted to correct)
1. In Abstract – Results: “EASR” is not defined elsewhere. Spell out or revise to
“estimated ASR”? “(“ missing in “late stage III/IV)”.
2. Methods, p. 4, 1st paragraph: Missing “.” (period) after “…Registry Board in
1991”
3. Results, p. 5, 2nd paragraph: “ASIR” was not previously defined.
4. Discussion, p. 6: “…the number OF cases”
5. Discussion, p. 7, stage section, 2nd paragraph: Missing “.” (period) after
“…pilot FIT screening in Ireland [22]”
Major Compulsory Revisions (which the author must respond to before a
decision on publication can be reached)
1. Methods, p. 4: The authors should provide information about how they defined
“treatment” (i.e., first course, all courses, etc.) and how complete the treatment
information was in the registry. If treatment was not complete, how might this
affect the results?
2. Methods, p. 4: Although the authors state the three diagnostic periods were
created to produce more stable results, it is still not clear why joinpoint regression
techniques were not used?
3. Methods, p. 4: The authors should provide information about how follow-up
was conducted? Did all cases have valid follow-up dates? If not, what was the
lost to follow-up rate and will the incomplete follow-up have any influence on the
findings?
4. Discussion, p. 7, stage section: The authors state that the changing trends in
unstaged cancers is likely represented among the increase in late stage but do
not specifically offer a reason for the changes. Better staging techniques? Better
data collection? It is likely that changing trends are partly attributable to changes
in diagnostic and staging techniques and possible improvements in data
collection. The authors should discuss these likely causes in the discussion.
5. Discussion, p. 7: The authors make no mention of colonoscopy as a screening
tool. When considering the impact of screening methods in the population it is
difficult to assess the total impact of screening without also considering one of
the most effective screening modalities - unless colonoscopy is not
recommended in Ireland.
Level of interest: An article of importance in its field
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a statistician.
Declaration of competing interests:
I declare that I have no competing interests.