Wluka 2021.

Study name	Knee osteoarthritis pain study (KOPS)
Methods	Double‐blind, parallel arm, placebo controlled 2‐arm RCT 12 weeks
Participants	Adults aged 40‐75 with knee OA as defined by the ACR clinical and radiographic criteria Pain intensity of ≥ 30 on 0‐100 pain scale
Interventions	Amitriptyline 25 mg Placebo
Outcomes	Pain intensity WOMAC total score Moderate pain relief (30% reduction) Substantial pain relief (50% reduction)
Starting date	07 July 2015
Contact information	Mrs Aruna Kartik Department of Epidemiology and Preventive Medicine, Monash University, Alfred Hospital, Commercial Road, Melbourne, VIC 3004, Australia jointstudy@monash.edu
Notes

ACR: American College of Rheumatology; AE: adverse event; BPI: Brief Pain Inventory; IBS: irritable bowel syndrome; MNSI: Michigan Neuropathy Screening Instrument; NRS: numeric rating scale; NSAID: non‐steroidal anti‐inflammatory drug; OA: osteoarthritis; OMERACT‐OARSI: Outcome Measures in Rheumatology‐Osteoarthritis Research Society International; PGIC: Patient Global Impression of Change; RCT: randomised controlled trial; s; TENS: transcutaneous electrical nerve stimulation; VAS: visual analogue scale;