Tétreault 2016.

Study characteristics
Methods	Design: parallel Duration: 16 weeks Assessment: baseline and post‐intervention Country: USA
Participants	Pain condition: knee OA Population: adults aged 45‐80 with knee OA Minimum pain intensity: ≥ 5 on 0‐10 scale Inclusion criteria Diagnosed by a clinician for knee OA, fulfilled ACR criteria, and had knee pain for at least 1 year Knee pain intensity of at least 4/10 Exclusion criteria Physical and mental health comorbidities Total participants randomised: 40 Age in years (mean, SD): 58.7 (7.6) Gender: 21/40 were female Pain duration in years (mean, SD): 10.54 (9.1)
Interventions	Placebo n = 21 Inert Identical appearance to duloxetine, matched dosing Duloxetine 60 mg n = 19 SNRI Fixed dose, forced titration
Outcomes	Pain intensity Physical function Mood AEs SAEs
Missing data methods	Completer‐only analysis
Funding source	Partly pharmaceutical: Eli Lilly Pharmaceuticals (IIT number: F1J‐US‐XO61). This research was also partially supported by grants from National Institute of Neurological Disorders and Stroke, ninds.nih.gov (NS035115), and National Center for Complementary and Integrative Health, nccih.nih.gov (AT007987) of the US National Institutes of Health. PT was supported by postdoctoral fellowships from the Canadian Institutes of Health Research (CIHR), cihr‐irsc.gc.ca.
Conflicts of interest	No financial or other relationships that might lead to a COI
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomisation methods not specified
Allocation concealment (selection bias)	Unclear risk	Allocation procedures not specified
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Double‐blind, identical study drugs, matched dosing
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Self‐reported outcomes from blinded participants
Incomplete outcome data (attrition bias) All outcomes	High risk	Completer analysis only Attrition Total: 21/60 (35.0%) Attrition per arm NR
Selective reporting (reporting bias)	Low risk	Outcomes match those in the protocol
Other bias	Low risk	No other sources of bias identified