It is very difficult to know. I empathise with this dilemma but having got through I can tell you my story. As I tapered stiffness returned and a little pain. My blood markers were ‘no inflammation’ from the time I started prednisone so I took it that prednisone was working. When I got to 1mg I still felt stiffness and when I stopped completely I had stiffness and some pain which gradually lessened over 12-18 months. I now know that this is normal. There is no magic end to it once finishing the medication but I found exercise slowly helped me regain strength and reduced stiffness. Now, I am entering my third year since stopping prednisone. I go to the gym twice a week for 3o minutes sessions and Pilates once a week in a small group on reformers. The only pain I get now is muscle pain from the exercise! Very minor stiffness when I get up but a few stretches and that’s it. Best of luck and kick the pills if you can as it is a nasty medication.