Lee 1989.

Methods	Single‐centre parallel‐group randomized controlled trial conducted in Jamaica
Participants	149 adults undergoing upper GI endoscopy for the first time. 79 men with a mean age of 52.5 years (range 18 to 81) and 70 women with a mean age of 46 years (17 to 82 years)
Interventions	Intravenous administration of: Diazepam to a maximum of 0.15 mg/kg Midazolam to a maximum of 0.07 mg/kg No sedation (not used in this review) (47 participants)
Outcomes	Measured during the procedure: Participant co‐operation Difficulty performing procedure Measured 24 to 48 hours after the procedure: Anterograde amnesia (defined by number of participants who recalled the procedure) Discomfort/pain (measured in the trial as 'uncomfortable')
Notes	Conflicts of interest or funding sources were not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not blinded
Blinding of outcome assessment (detection bias) All outcomes	High risk	The endoscopist who was unaware of the drug used completed a questionnaire to assess the participant co‐operation and difficulty performing procedure outcomes, but anterograde amnesia and discomfort/pain were not assessed in a blinded fashion (no information about participant blinding)
Incomplete outcome data (attrition bias) All outcomes	Low risk	No withdrawals
Selective reporting (reporting bias)	Unclear risk	No clear evidence that measured outcomes were not reported (trial protocols were not sought for confirmation)
Other bias	Low risk	None expected