Park 2011.

Methods	Generation of allocation sequence: Computer generated Allocation concealment: Sealed envelopes Blinding: Single blinded (patient only) Inclusion of all randomised patients: No (25 excluded due to poor bowel prep)
Participants	Number: 329 (235M:94F) Age: CAC group 61.3 +/‐ 10.3 years. RC 59.3 +/‐ 10.2 years. Source: Chonnam National University Hospital Inclusion criteria: Patients 18 years or older who were able to give informed consent and were scheduled for elective colonoscopic EMR. Exclusion criteria: Previous colorectal surgery, colonic stricture, obstructing tumour, other acute surgical conditions (such as severe colitis, toxic megacolon, Ischaemic colitis or acute GI bleed).
Interventions	Colonoscope: Regular colonoscopes without variable stiffness function: CF‐240 or CF‐Q240 (Olympus Medical Systems, Tokyo, Japan. Bowel Preparation: 3 day low residue diet, followed by 4L polyethylene glycol solution. Intra‐procedure medications: not stated. Endoscopist experience: "Experienced" >3000 procedures between them. Caps: Soft, transparent plastic cap, 14mm outer diameter and protrudes 4mm. D‐201‐12704 (Olympus).
Outcomes	Included in review: Caecal intubation time, polyp detection rate Excluded from review: Total procedure time, withdrawal time, polyp miss rate, time required for EMR.
Notes	Location: South Korea Source of funding: Not stated Attempts to clarify information: Not necessary Language of Publication: English
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer generated
Allocation concealment (selection bias)	High risk	Not concealed as not blinded
Blinding (performance bias and detection bias) All outcomes	High risk	Endoscopist not blinded
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	25 excluded from analysis due to poor bowel prep.
Selective reporting (reporting bias)	Low risk	Appropriate outcomes reported.
Other bias	Unclear risk	Source of funding not stated.