Review for 10.1186/s12876-022-02566-6 (2022)

Title: Association of gallbladder diseases with risk of gastrointestinal polyps
Version: 2 Date: 08 Aug 2022
Reviewer's report:
"PEER REVIEWER ASSESSMENTS:
OBJECTIVE - Full research articles: is there a clear objective that addresses a testable research
question(s) (brief or other article types: is there a clear objective)?
No - there are minor issues
DESIGN - Is the current approach (including controls and analysis protocols) appropriate for
the objective?
No - there are minor issues
EXECUTION - Are the experiments and analyses performed with technical rigor to allow
confidence in the results?
No - there are minor issues
STATISTICS - Is the use of statistics in the manuscript appropriate?
No - there are issues with the statistics in the study
INTERPRETATION - Is the current interpretation/discussion of the results reasonable and not
overstated?
No - there are minor issues
OVERALL MANUSCRIPT POTENTIAL - Is the current version of this work technically
sound? If not, can revisions be made to make the work technically sound?
Maybe - with major revisions
PEER REVIEWER COMMENTS:
GENERAL COMMENTS: The overall purpose of this study is important and justified. It’s
interesting and unique data. However, the description of the design, analyses and interpretation
could be clearer. There are too many tables, many containing superfluous information. It would
benefit from having the tables collapsed into 2 or 3 containing the most pertinent data.
REQUESTED REVISIONS:
Abstract
• Background and aims are disjointed. Aim needs to be clearer and fit with the methods
described.
Intro
• The authors state that “Gastric and CRC are THE most common cancers globally” – should
add ‘among’ the most common cancers globally.
• Should define gallbladder disease – what is included in the definition of gallbladder disease?
Methods –
• Did the study include ALL eligible people in the period 2015-2020?
• Clearly define whether lesions found in the splenic flexure are in the proximal or distal colon;
the way it is currently worded, it is unclear.
• Need more information about gastroscopy and colonoscopy procedures – similar to the detail
given for ultrasound.
• Statistical analysis – add information about how the models estimating ORs were built and
how confounders were identified.
• Need to define whether your 4 endpoints are mutually exclusive. In other words, make it clear
that your gastric polyp group is ‘any gastric polyp’ or ‘only gastric polyps (and no colorectal
polyps)’ – same with the other groups.
Results
• When describing Table 1 differences, please ensure you include all significant variables in
your description of each comparison.
• Description of Table 3, Table 5 and Table 6 – ensure there is consistency with the cut off – for
example, in the table it says >=0.5 and in the text it says >0.5 (this actually occurs throughout
the manuscript).
• Table 3: the confidence interval and p-value in table 3 doesn’t match the ‘2.21, 95% CI: 1.25–
3.24, P = .004’ given in the text.
• Misleading description of ‘incidence’ of polyps throughout – surely it should be described as
‘prevalence’ in this cross-sectional study?
• The results section doesn’t really mention gallbladder stones yet the first sentence of the
discussion says there was no association for gallstones. This should be addressed in the results
section first.
Discussion
• The following sentence doesn’t make sense to me?: “No correlation could be found between
gallbladder stones and gastrointestinal polyps, although it has been reported that gastric polyps
can transform into gastric cancer [2].”
• The authors talk about previous studies looking at gallstones and gastric cancer and that
the findings in this submitted manuscript ‘is consistent with’ this previous study – but this is
misleading given the study considered here isn’t reporting on gastric cancer.
• The discussion talks about age, yet currently the study presented doesn’t look into age. Suggest
doing analyses stratified by age.
• In general, the discussion is a little jumbled up and would benefit from being edited for
coherence.
• There should be greater emphasis on how small some of the groups are – for example, only 14
people with gastric polyps have gallbladder polyps. This is very low statistical power to draw
any conclusions.
Tables
• Table 1 – needs a footnote to say what each P value column is comparing.
• Table 2 doesn’t really contribute to the aim of the paper – this table is solely looking at risk
factors for gastrointestinal polyps. Only the row on gallbladder polyps seems relevant? (as would
gallstones be relevant). Suggest collapsing the tables to show the most relevant data and avoid
having so many small tables.
• As above, Table 4 contains a lot of unnecessary data that doesn’t contribute to the main aim
of the paper. Combine the key variables in Tables 4, 5 (the data from Table 5 should be given
for right-sided polyps as well) and Table 6, 7 and 8– just to show the relationship between
gallbladder diseases and various polyp outcomes. You could have one table showing GB polyps
and GB stones and the various polyp outcomes and one table showing the stratified analyses by
sex – and add a stratified analyses by age."