van Steenberghe 1986.

Methods	Study 1. Randomised, double blind, 5 parallel groups. Single oral dose Medication administered when baseline pain reached a moderate to severe intensity Pain assessed at 0, 30, 60 mins, then hourly to 6 hours
Participants	Oral surgery on the periodontium N = 73 M 43, F 36 Mean age 40 years
Interventions	Codeine 60 mg, n = 20 Ciramadol 15 mg, n = 13 Ciramadol 30 mg, n = 15 Ciramadol 60 mg, n = 20 Placebo, n = 15
Outcomes	PI: standard 10 cm VAS, but baseline pain not reported using this scale Adverse events
Notes	Oxford Quality Score: R1, DB1, W1. Total = 3 No details about timing of rescue medication
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Unclear risk	Not described
Allocation concealment?	Unclear risk	Not described
Blinding? All outcomes	Unclear risk	Not described