Mahler 2003.

Methods	R, DB, AC, parallel groups Gel applied with gentle massage to affected area 3 times daily, without occlusion, for 10 days Assessed at baseline, 3, 10 days in clinic and daily patient diary
Participants	First‐degree ankle or knee sprains, first‐degree muscle strains and mild‐to‐moderate contusions n = 100 M 69, F 31 Mean age 32 years Mean baseline pain with activity ≥ 65 mm
Interventions	DHEP lethicin gel, 3 x 5 g (= 65 mg) daily, n = 52 DHEP gel, 3 x 5 g (= 65 mg) daily, n = 48 All participants treated with ice at site of inflammation for first 48 hours, but no immobilisation allowed Rescue medication: paracetamol 500 mg if strictly necessary
Outcomes	PGE: 4‐point scale (responder = "good" or "excellent") Pain on movement: 100‐mm VAS (mean data) Adverse events Withdrawals
Notes	Oxford Quality Score: R2, DB2, W1. Total = 5
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Computer‐generated randomization list"
Allocation concealment (selection bias)	Unclear risk	Not described
Blinding (performance bias and detection bias) All outcomes	Low risk	Pharmaceutically inert colouring agents added to reference formulation so that gels were indistinguishable
Incomplete outcome data (attrition bias) All outcomes	Low risk	All participants included in responder analysis
Size	High risk	< 50 participants in each treatment arm