Massad 2006.

Methods	Randomized controlled trial
Participants	Age (years, mean ± SD): Group I = 38.2 ± 14.7, Group II = 40.3 ± 16.6, Group III = 43.6 ± 17.4, Group IV = 43.0 ± 16.7 Gender (M:F): Group I = 25:25, Group II = 16:35, Group III = 18:32, Group IV = 20:30 Inclusion criteria: age 15 years to 90 years old, ASA I‐III, minor elective surgery demanding laryngeal mask Exclusion criteria: patients with difficulty in communication, not co‐operative, below 14 years, received any type of analgesia before arriving operating room including local anaesthesia, positive past history of hypersensitivity to anaesthetic agents or decompensated heart failure Recruitment: 200 adult patients randomly assigned (50 in each group) Setting: Jordan
Interventions	Admixture Pretreatment alone Pretreatment with venous occlusion 200 patients, divided into four groups: Group I the control group, 1% propofol alone Group II 1% propofol premixed with 40 mg lidocaine Group III 1% propofol 60 sec after 40 mg of lidocaine pretreatment Group IV lidocaine 40 mg pretreatment venous occlusion Pain was graded during induction
Outcomes	Pain intensity assessed on 3‐point scale 0 = no pain 1 = pain 2 = pain with behavioural changes 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	Low risk	"Blinded by resident doctor as an outcome assessor."
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