https://www.webmd.com/rheumatoid-arthritis/an-overview-of-rheumatic-diseases
This may have been the article that started me me on the path to a diagnosis. My biggest problem was the morning stiffness and pain that eased after moving around. Pmr seemed likely.
I understand there is no exactness in matching test results to a specific disease but you have to start somewhere. Symptoms and blood test results may/can lead to a probable diagnosis. Prednisone helped me immensely and quickly.
These discussions always end up using the terms: likely, probably, may, maybe, seems like, generally, could be.
No exact science