Ibarra 1993

Methods	Randomised, double blind, active control (ketorolac), single IM dose. Study duration 6 h Baseline PI = moderate or severe Self assessment at t = 0, 0.5, 1.0, then hourly up to 6 h.
Participants	Orthopaedic surgery N = 97 M 40, F 57 Mean age = 35 years
Interventions	Dipyrone 2.5 g IM, n = 48 Ketorolac 30 mg IM, n = 49 (48 analysed for efficacy)
Outcomes	PI: non‐standard 5 point scale (none‐very severe) PR: standard 5 point scale (0‐4) PGE: standard 5 point scale
Notes	Oxford Quality Score: R1, DB1, W1. Total = 3
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding (performance bias and detection bias) All outcomes	Unclear risk	"dual observer technique"