Reddy 2001.

Methods	Double‐blind randomized controlled trial
Participants	Age (years, mean ± SD): Group 1 = 33.5 ± 13.5, Group 2 = 39.8 ± 14.2, Group 3 = 41.4 ± 18.3 Gender (M:F): Group 1 = 12:8, Group 2 = 9:11, Group 3 = 10:10 Inclusion criteria: ASA I‐II, elective orthopaedic and gastrointestinal procedures Exclusion criteria: N/A Recruitment: 60 adult patients randomly assigned (20 in each group) Setting: Singapore
Interventions	Pretreatment with venous occlusion Group 1 received 5 ml 0.9% sodium chloride solution intravenously as the control Group 2 received ondansetron 4 mg (2 mg/ml) diluted with water into a 5‐ml solution Group 3 received 50 mg lidocaine (5 ml of 1% solution) intravenously
Outcomes	Pain intensity assessed on 4‐point scale 0 = no pain 1 = mild pain (pain in response to questioning only without any behavioural signs) 2 = moderate pain (pain in response to questioning and accompanied by behavioural sign or pain reported spontaneously without questioning) 3 = severe pain (strong vocal response or response accompanied by facial grimacing, arm withdrawal, or tears) Outcomes reported and used Incidence of high‐intensity pain Incidence of pain Outcomes sought but not reported Adverse effects Patient satisfaction
Notes	Period of the study: dates not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Subjects were randomly allocated to one of three groups by the drawing of lots."
Allocation concealment (selection bias)	Unclear risk	N/A
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"All syringes of test solution were prepared by another investigator and covered so that the investigator who assessed the patient's response was unaware of the nature of the solution."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"All syringes of test solution were prepared by another investigator and covered so that the investigator who assessed the patient's response was unaware of the nature of the solution."
Incomplete outcome data (attrition bias) All outcomes	Low risk	No withdrawals
Selective reporting (reporting bias)	Unclear risk	N/A
Other bias	Low risk	The study appears to be free of other sources of bias