Review for 10.1186/s12876-021-01877-4 (2021)

Reviewer’s report
Title: 
Cecal Retroflexion is Infrequently Performed in Routine Practice and the
Retroflexed View is of Poor Quality
Version: 
3 
Date: 
24 May 2021
Reviewer's report:
This revision has adequately addressed comments raised previously. 
However, I would like to make 1 suggestion: since it is important to examine
right colon twice, but only 26.1% of colonoscopy in the study had examined
right colon x2, another important message from the study is that we need to raise
the awareness of examining right colon twice, in addition to inadequate RV. The
authors can include this message when they talk about education in the last
sentence of the last paragraph in Discussion.
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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
Are the methods sufficiently described to allow the study to be repeated?
Yes
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Yes
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Are the images in this manuscript (including electrophoretic gels and blots) free
from apparent manipulation?
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