Rastogi 2012.

Methods	Generation of allocation sequence: Opaque, sealed envelopes. Stratified by indication (screening or surveillance). Allocation concealment: Not stated Blinding: Not stated Inclusion of all randomised patients: No ‐ patients with inadequate bowel prep or where they could not reach the caecum were excluded from analysis.
Participants	Number: 427 randomised, 420 analysed (398M:22F) Age: CAC group 60.7 +/‐ 7.2 years. Standard group 61.3 +/‐ 7.3 Source: Tertiary care Veterans Affairs Medical Center, USA. Inclusion criteria: Referral for screening or surveillance colonoscopy and the ability to provide informed consent. Exclusion criteria: Previous surgical colonic resection, history of colorectal cancer or IBD, use of antiplatelet agents or anti‐coagulants precluding removal of polyps, poor general condition or any other reason to avoid prolonged procedure time, history of polyposis syndrome or HNPCC, inability to give informed consent.
Interventions	Colonoscope: CF‐H180AL (Olympus America Inc, Centervalley, Pennsylvania, USA). Bowel preparation: not stated. Intra‐procedure medication: IV midazolam +/‐ Meperidine or Fentanyl. Endoscopist: "Experienced" with more than 3000 colonoscopies each and more than 20 CAC procedures.
Outcomes	Included in review: Caecal intubation rate, caecal intubation time, Polyp detection rate Excluded from review: use of sedation/analgesia, polyp analysis, withdrawal time
Notes	Location: USA Source of funding: Endoscopic Research Center for Development Award (A. Rastogi) from the American Society for Gastrointestinal Endoscopy. 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 concealed as not blinded
Blinding (performance bias and detection bias) All outcomes	High risk	Not stated but endoscopist not blinded
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Patients excluded from data analysis when caecum not reached or when bowel prep was poor.
Selective reporting (reporting bias)	Unclear risk	Appropriate outcomes all reported.
Other bias	Low risk	None identified.