Does the Cap Increase the Finding of Polyps When Water Exchange Colonoscopy is Used

This will be a multi-site, multi-national, unblinded investigators, prospective Random
Control Trial (RCT). Randomization (WE, WE Cap-1, WE Cap-2) will be based on computer
generated random numbers placed inside opaque sealed envelopes. The envelope (in pre-arranged
order) will be opened to reveal the code when the colonoscopist is ready to insert the
endoscope to begin the examination. This will be a comparison of two different methods with
three arms (WE, WE Cap-1, WE Cap-2) to see which one is better at detecting adenomas.

Patients who are willing to participate will sign an informed consent before starting the
colonoscopy procedure. Separate parallel randomization will be set up at each site,
stratified by investigator and type of colonoscopy (screening or surveillance). Mode of
sedation will include unsedated (China, US West Los Angeles VA), minimally sedated (Taiwan),
on demand sedation (Italy, Czech Republic, US West Los Angeles VA), conscious sedation (US
Sacramento VA and Palo Alto VA) or full sedation with propofol (Taiwan). Randomization
(prepared by statistics consultant) will be carried out by the method of random permuted
block design (based on computer generated random numbers) with variable block sizes of 3 and
6. Gender will be used as a stratification factor.

Control Method: One arm of the study will include sedated/unsedated colonoscopy with water
(WE) as the control method. Residual air in the colon will be removed and water will be
infused to guide insertion through an airless lumen. Infused water will be removed by
suction, along with residual fecal debris, predominantly during insertion.

Study method: The other two arms entail the addition of a simple commercially available
accessory to the colonoscopy device: Cap -1 (Disposable Distal Attachment) or Cap-2, fitted
to the colonoscope per manufacturer instruction. The two arms include sedated/unsedated
colonoscopy with either a Cap-1 plus water or Cap-2 plus water.

Inclusion Criteria:

1. Male and female 50-75 yrs of age.

2. Positive screening for Fecal Immunochemical Test (FIT) or Fecal Occult Blood Test
(FOBT).

3. Subjects willing to undergo routine screening and surveillance colonoscopy.

Exclusion Criteria:

1. Patients who decline to provide informed consent.

2. Patients known to have colonic obstruction, inflammatory bowel disease, or active GI
bleeding requiring interventions.

3. Patients know to have prior history of severe diverticulitis/diverticulosis.