Methods	RCT, DB, multiple oral dose, crossover design. Self-assessed at t = 1/2. 1 hr and then hourly for 6 hrs. Medication allowed when pain of moderate to severe intensity
Participants	Lower third molar removal. n = 68 Age = Adults
Interventions	DHC 30 mg, n = 40 DHC 60 mg, n = 40 Placebo, n = 40
Outcomes	Outcome measures: PI (4 point scale ) standard PR (5 point scale) standard Global rating (5 point scale) standard Analgesic outcomes: TOTPAR at 6 hrs: DHC 30 mg : 3.3 DHC 60 mg: 4.7 Ibuprofen 400 mg: 10.0 Ibuprofen was significantly better than dihydrocodeine 30 mg or 60 mg (P < 0.01)
Notes	Remedication: If remedicated at t< 6 hrs the initial PI score and PR score of zero were used for all further time points Withdrawals: 3 patients withdrew. Adverse effects: Single dose adverse effects data was not presented. Quality score: 4
Risk of bias
Item	Authors’ judgement	Description
Allocation concealment?	Yes	A - Adequate

Abbreviations:

DHC = dihydrocodeine;

R = randomised;

DB = double blind;

PI = pain intensity;

PR = pain relief;

AE = adverse effect.