Pappas 2001.

Methods	Randomized observer‐blinded study
Participants	N = 123, age 4 months to 7 years, ASA I‐II, scheduled for infra‐umbilical surgery 4 groups ‐ Group 1: isoflurane anaesthesia and early removal of the LMA; Group 2: isoflurane anaesthesia and late removal of the LMA; Group 3: sevoflurane anaesthesia and early removal of the LMA; Group 4: sevoflurane anaesthesia and late removal of the LMA
Interventions	Type of LMA: LMA Classic Early removal ‐ The LMA was removed at twice the age‐adjusted MAC end‐tidal concentration of isoflurane/ sevoflurane Late removal ‐ The LMA was removed when patients were awake i.e. in the presence of spontaneous eye opening, grimacing, coughing, and purposeful movement of extremities without any physical stimulation
Outcomes	Desaturation Airway reactivity Vomiting Bronchospasm Overall airway adverse event
Notes	Induction & maintenance ‐ according to study groups Spontaneous breathing Supplemental regional analgesia
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Assigned to one of the four groups using computer‐generated random sequence"
Allocation concealment (selection bias)	Unclear risk	COMMENT ‐ No description of method of allocation concealment
Blinding (performance bias and detection bias) Of outcome assessor to all outcomes	Low risk	"A research nurse, blinded to the anaesthetic drug and technique, recorded all study variables"
Incomplete outcome data (attrition bias) All outcomes	Low risk	COMMENT ‐ 123 patients randomized and four excluded after randomization (3.3% dropout). Authors have done available case analysis
Selective reporting (reporting bias)	Low risk	COMMENT ‐ Though no explicit statement, the outcomes mentioned in methodology have been reported