Methods	RCT, DB single oral dose, 5 parallel groups Medication administered when baseline pain reached a moderate to severe intensity Pain assessed at 0, 15, 30, 45, 60, and 90 mins, then at 2, 3, 4, 5, 6, 7, 8, and 12 h
Participants	Impacted third molar extraction Mean age 22 years N = 482 M = 124, F = 358
Interventions	Celecoxib 400 mg, n = 151 Celecoxib 200 mg, n = 90 Rofecoxib 50 mg, n = 150 Ibuprofen 400 mg, n = 45 Placebo, n = 45
Outcomes	PI: std 4-point scale PR: std 5-point scale PGE: std 5-point scale Time to use of rescue medication Number of participants using rescue medication
Notes	Oxford Quality Score: R2, DB2, W1 Participants asked to refrain from rescue medication for 1.5 h
Risk of bias
Bias	Authors’ judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	“computer-generated allocation schedule”
Allocation concealment (selection bias)	Low risk	Participants allocated to next randomisation number (lowest for moderate pain, highest for severe pain)
Blinding (performance bias and detection bias) All outcomes	Low risk	Double-dummy method. Each active treatment had matching placebo tablets or capsules
Incomplete outcome data (attrition bias) All outcomes	Low risk	Participants accounted for; analysis appropriate for relevant time interval
Other bias	High risk	Small treatment group size (90 to 151 coxib, 45 to 50 ibuprofen, and placebo participants)