Fig. 1From: A mechanism-based proof of concept study on the effects of duloxetine in patients with painful knee osteoarthritisStudy design and timeline. Patients are randomized to either duloxetine followed by placebo (sequence 1) or placebo followed by duloxetine (sequence 2). Approximate dates for each study event (visits or phone calls) are highlighted in the timeline. Abbreviations: DLX, duloxetine; PBO, placebo; QD, daily doseBack to article page