Lyons 1996.

Methods	Double‐blind randomized controlled trial
Participants	Age (years, mean ± SD): Group 1 = 41.1 ± 18.1, Group 2 = 38.3 ± 16.9, Group 3 = 40.6 ± 17.3 Gender (M:F): Group 1 = 33:19, Group 2 = 32:19, Group 3 = 29:18 Inclusion criteria: age 16 years to 70 years old, ASA I‐II, a variety of elective orthopaedic surgery Exclusion criteria: patients with difficult venous access and those requiring a rapid sequence induction Recruitment: 150 adult patients randomly assigned (52, 51 and 47 in pethidine, lidocaine and saline group respectively) Setting: Ireland
Interventions	Pretreatment alone Patients were randomly allocated into 3 groups: pethidine 25 mg (n = 52), Group 1 lidocaine 10 mg (n = 51), Group 2 0.9% saline 1 ml (n = 47), Group 3 pretreatment 10 sec before propofol 5 ml injection over 15 sec Premed with diazepam 0.15 mg/kg 90 min before surgery
Outcomes	Pain intensity assessed on 4‐point scale 0 = no pain 1 = mild pain 2 = moderate pain 3 = severe pain 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)	Unclear risk	N/A
Allocation concealment (selection bias)	Unclear risk	N/A
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	N/A
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	N/A
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