Patient characteristics in knee, hip and back pain patients participating in patient education and exercise therapy. a comparison of 46, 273 patients from the glad registries in Denmark. Issue 1 (April 2020) - Roos, E.M.; Grønne, D.T.; Ris, I.; Kjaer, P.; Hartvigsen, J.; Skou, S.T.; Kongsted, A.