Louthrenoo 2007.

Methods	Randomised controlled trial Multi‐centre (five medical schools in Thailand) Double‐blind Piroxicam‐controlled Parallel‐group
Participants	Participants with tibiofemoral X‐ray confirmed Kellgren‐Lawrence grade II or III OA according to ACR criteria between 40 and 65 years of age, with knee pain of at least 40 mm on at least two items of the WOMAC A, on a 0 to 100‐mm VAS scale, for at least 15 days
Interventions	Diacerein 100 mg/ d (N = 86) versus piroxicam 20 mg/d (N = 85). 16 weeks
Outcomes	WOMAC A, B, C SF‐36 Paracetamol consumption
Notes	Supported by a grant from TRB Chemedica International
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Each participant was randomly assigned to a treatment group using a randomisation table generated by a validated computer software
Allocation concealment (selection bias)	Unclear risk	Not described
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not described
Blinding of outcome assessment (detection bias) Clinical outcomes	Unclear risk	Not described
Blinding of outcome assessment (detection bias) Radiographic outcomes	Low risk	Not applicable
Incomplete outcome data (attrition bias) All outcomes	High risk	A good description of withdrawals and the reasons for them were provided. 171 were randomly assigned (diacerein 86 and control 85); however, ITT analysis was performed in only 161 (82 diacerein, 79 control). 10 participants (four diacerein, six control) were excluded from ITT because they did not take any dose of medication. 150 participants completed the study
Selective reporting (reporting bias)	Low risk	All data were properly reported