Harada 2009.

Methods	Generation of allocation sequence: Sealed envelopes Allocation concealment: Not applicable as not blinded. Blinding: Not stated but unblinded to endoscopists Inclusion of all randomised patients: Yes
Participants	Number: 592 (391M:201F) Age: Hood group ‐ 62.6 years +/‐ 63.7. No Hood ‐ 62.7 years +/‐ 64.0 (mean) Source: A single Japanese tertiary referral centre Inclusion criteria: Screening/surveillance total colonoscopy. Exclusion criteria: Emergency, therapeutic or EUS procedures. Poor bowel preparation.
Interventions	Colonoscope: PCF‐Q240ZI, PCF‐Q260AI, PCF‐P240AI (Olympus Optical Co, Ltd, Japan). Bowel Preparation: Colonic lavage with polyethylene glycol. Intra‐procedure medication: 2‐5mg midazolam as required for pain IV, Scopolamine butyl bromide or glucagon as antispasmodic. Endoscopists: 3 with >5000 caecal intubations, 1 with >3000 caecal intubations and 2 with <1000 caecal intubations. Cap: D‐201‐13404, D‐201‐012704, D‐201‐11804 (Olympus Medical Systems, Tokyo, Japan).
Outcomes	Included in review: Caecal intubation rate, caecal intubation time, polyp detection rate, Pain during procedure Excluded from review: Withdrawal time (?sedation/analgesia requirements)
Notes	Location: Japan Source of funding: Not stated Attempts to clarify information: Not required Language of Publication: English
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Sealed envelopes.
Allocation concealment (selection bias)	High risk	Not blinded
Blinding (performance bias and detection bias) All outcomes	High risk	Not blinded to endoscopist.
Incomplete outcome data (attrition bias) All outcomes	Low risk	All patients included in data analysis.
Selective reporting (reporting bias)	Low risk	Appropriate outcomes reported.
Other bias	Unclear risk	Source of funding not stated.