Han 2010.

Methods	Double‐blind randomized controlled trial
Participants	Age (years, mean ± SD): Group 1 = 47 ± 14.5, Group 2 = 51 ± 13.5, Group 3 = 50 ± 14.4 Gender (M:F): Group 1 = 20:20, Group 2 = 20:20, Group 3 = 19:21 Inclusion criteria: age 20 years to 65 years old, ASA I‐II, elective surgery Exclusion criteria: patients with self‐confirming allergies to opioids, local anaesthetics, asthma, neurological deficits and those who had received analgesics or sedatives within the previous 24 hours Recruitment: 120 adult patients randomly assigned (40 in each group) Setting: Korea
Interventions	Admixture Patients were allocated randomly into one of three groups (n = 40, in each) The patients in the remifentanil group (Group 1) received remifentanil 0.5 mcg/kg IV pretreated for 30 seconds before a micro emulsion propofol injection The patients in the lidocaine group (Group 2) received propofol 2 mg/kg premixed with 40 mg lidocaine over a 60 second period. The patients in the combination group (Group 3) received both remifentanil and lidocaine
Outcomes	Pain intensity assessed on 4‐point scale 0 = no pain 1 = mild pain (a minor verbal/facial response or motor reaction to the injection) 2 = moderate pain (a clear verbal/facial response or motor reaction to the injection) 3 = severe pain (the patient both complained of pain and withdrew their arm) Outcomes reported and used Incidence of high‐intensity pain Incidence of pain Adverse effects Outcomes sought but not reported 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	"The patients were allocated randomly to one of three groups using a computer generated randomization list manipulated by a statistician in a sealed envelope."
Allocation concealment (selection bias)	Unclear risk	N/A
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"The patients, anaesthesia providers and investigators who scored the movements were blinded to the treatment group."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"The patients, anaesthesia providers and investigators who scored the movements were blinded to the treatment group."
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