Zahmatkash 2011.

Methods	RCT, DB, parallel groups Duration 6 weeks Assessment weekly
Participants	Osteoarthritis of the knee N = 92 M = 2, F = 90 Mean age 52 years (SD 12.4)
Interventions	Salicylate (unspecified), n = 46 Herbal (cinnamon, ginger, mastic, sesame oil) ointment, n = 46 2 g ("a knuckle") of ointment massaged over knee for 1 minute, x 3 daily, for 6 weeks
Outcomes	PI: 100 mm VAS Morning stiffness: 100 mm VAS Nightly pains: 100 mm VAS Walking pain in previous 24 h assessed each week Use of rescue medication (paracetamol, sedatives)
Notes	Oxford Quality Score: R1 DB1 W1. Total = 3/5 Participants had to have "stability in taking medication within last two weeks", but it is unclear whether this medication was continued during the study
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method used to generate random sequence not described. Used block randomisation.
Allocation concealment (selection bias)	Unclear risk	Method not described
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Method not described
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Withdrawals < 10% (apparently lost to follow‐up). No indication of compliance or tolerability
Size	High risk	< 50 participants per treatment arm

DB: double‐blind; F: female; LOCF: last observation carried forward; M: male; N: total number in study; n: number in treatment arm; PI: pain intensity; PR: pain relief; R: randomised; RCT: randomised controlled trial; W: withdrawals