Kwak 2008.

Methods	Double‐blind randomized controlled trial
Participants	Age (years, mean ± SD): Group L = 48 ± 14.5, Group D = 50 ± 13.5, Group LD = 48 ± 14.4, Group N = 45 ± 14.5 Gender (M:F): Group L = 15:20, Group D = 13:22, Group LD = 11:24, Group N = 10:25 Inclusion criteria: age 16 years to 73 years old, ASA I‐II, elective surgery Exclusion criteria: patients had received sedative or analgesic medication within 24 hours before surgery; had known allergy to any drugs; had renal, hepatic, or cardiac problems; had neurologic deficits and psychiatric disorders; or required a rapid sequence induction Recruitment: 142 adult patients randomly assigned (140 were analysed, 35 in each group) Setting: Korea
Interventions	Pretreatment with venous occlusion No premedication was given Patients were randomized to receive pretreated lidocaine 20 mg (Group L), dexamethasone 6 mg (Group D), combination lidocaine 20 mg and dexamethasone 6 mg (Group LD), or normal saline (Group N) with venous occlusion for 1 minute, followed by administration of 25% of the total calculated dose of propofol (2.5 mg/kg) into a dorsal hand vein
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 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	Computer‐generated table was used
Allocation concealment (selection bias)	Unclear risk	N/A
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"An anaesthesiologist who was not involved in this study prepared identically coded syringes."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"A study‐blinded anaesthesiologist evaluated the intensity and incidence of pain."
Incomplete outcome data (attrition bias) All outcomes	Low risk	"Of the 142 patients enrolled, 2 were excluded due to difficulty with venous cannulation."
Selective reporting (reporting bias)	Unclear risk	N/A
Other bias	Low risk	The study appears to be free of other sources of bias