Roth 2004.

Methods	R, DB, PC, parallel groups Assessed at weeks 1, 6 and 12
Participants	OA knee, radiologically diagnosed, symptomatic, with a flare of pain at least 3 days per week for a month, WOMAC used N = 326 M 105, F 221 Mean age 64 years Mean baseline pain 13/20 WOMAC
Interventions	(1) Diclofenac 1.5% (Pennsaid) n = 164 (2) Vehicle solution control n = 162 1.3 ml applied around knee 4 x daily for up to 12 weeks Rescue medication: paracetamol up to 1.3 g daily
Outcomes	Change in pain and physical function from baseline. Patient global assessment (5 pt scale) BOCF Adverse effects and dermatological assessment of the knee
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 schedule by outside consultant"
Allocation concealment (selection bias)	Low risk	Remote allocation. Each site assigned a series of numbers and kits. Participants assigned sequentially
Blinding (performance bias and detection bias) All outcomes	Low risk	"The two study solutions were identical clear, colourless liquids in opaque bottles with labels identical except for patient identification number"
Incomplete outcome data (attrition bias) All outcomes	Low risk	Imputation using BOCF where necessary. "Other" withdrawals < 10%
Study duration	Low risk	12 weeks
Size	Unclear risk	50 to 200 participants per treatment arm