Review for 10.1186/s12876-017-0612-y (2017)

Reviewer ’s report  
 
Title: Findings in Young Adults at Colonoscopy from a Hospital Service Database Audit  
 
Version: 0 Date: 17 Nov 2016  
 
Reviewer: Moe Kyaw  
 
Reviewer's report:  
 
This is a retrospectiv e study of symptomatic patients undergoing colonoscopy for various 
indications. Prevalence of lesions was compared between younger adults (<50) and older adults.  
Findings were reported of 2064 subjects. Older adult had more CRC precursor lesions (12.9%) 
compared to younger adults (4.3%). SSA/P was were more frequently observed as  precursor 
lesions in the younger adults compared to older adults.  
 
Major comments  
Introduction  
There are existing studies reporting colonoscopy findings of young symptomatic and 
asymptomatic subjects. This will be of interest for the reader. For asymptomatic subjects, reports 
come from those screening programmes where screening started at age 40, and compared with 
older screening subjects. Suggest adding into the introduction a brief description of past studies 
and how this current study will add novel information to existing data.  
 
Methods  
Suggest reviewing a longer period than one year - as prevalence of precursor lesions are likely to 
be low, it will be difficult to carry out any subgroup analysis of different precursor lesions.  
 
Results  
If the sample size was larger, SSA/P contributing to  higher significant proportion to overall 
precursor lesions will be more meaningful. With the denominator being small (11/21), it may be 
difficult to convince the reader with any inferential analysis.  
Conducting a subgroup analysis of 11 subjects with SSA /P to investigate co -occurrence with 
conventional adenomas may not be meaningful.  
 
Conclusion  
Again, as the conclusion is based on the subgroup analysis of precursor lesions from 21 subjects 
in the young group, a larger sample size will provide more suppo rting evidence.  
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to t he 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.  
 
No 
 
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 wha t 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:  
 
Acceptable  
 
Declaration of competing interests  
Please complete a d eclaration of competing interests, considering the following questions:  
 
1. Have you in the past five years received reimbursements, fees, funding, or salary from an  
organisation that may in any way gain or lose financially from the publication of this  
manu script, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose  
financially from the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applying for any patents relating to the content of the  
manuscript?  
 
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds  or has applied for patents relating to the content of the manuscript?  
 
5. Do you have any other financial co mpeting interests?  
 
6. Do you have any non -financial competing interests in relation to this paper?  
 
If you can answer no to all of the above, write 'I declare that I have no competing interests' 
below.  If your reply is yes to any, please give details below.  
 
No competing interests to declare  
 
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