for the main comparison.

Ibuprofen plus codeine compared with placebo for acute postoperative pain
Population: adults with moderate or severe acute postoperative pain Settings: community or hospital Intervention: ibuprofen 400 mg + codeine 25.6 mg to 60 mg Comparison: placebo
Outcomes	Probable outcome with		Relative effect and NNT or NNH (95% CI)	Number of studies, events	Quality of the evidence (GRADE)	Comments
	Comparator	Intervention
At least 50% of maximum pain relief over 4 to 6 h	180 in 1000	640 in 1000	RR 4.1 (2.8 to 5.9) NNT 2.2 (1.8 to 2.6)	4 studies 443 participants 208 events	High	Adequate numbers of studies, participants and events. Consistency across studies
Participants with at least 1 adverse event	180 in 1000	280 in 1000	RR 1.2 (0.84 to 1.7) NNH not calculated	4 studies 443 participants 109 events	Moderate	Adequate numbers of studies, participants, but moderate number of events. Consistency across studies. Single dose studies may not reflect clinical practice
Participants with a serious adverse event	No serious adverse events	Low	Studies underpowered to detect rare events
Deaths	No deaths	Low	Studies underpowered to detect rare events
CI: confidence interval; NNH: number needed to treat to harm; NNT: number needed to treat for benefit; RR: Risk Ratio
GRADE Working Group grades of evidence High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate.