Evaluating associations of joint swelling, joint stiffness and joint pain with physical activity in first-degree relatives of patients with rheumatoid arthritis: Studies of the Aetiology of Rheumatoid Arthritis (SERA), a prospective cohort study.
Hughes-Austin JM, Ix JH, Ward SR, Weisman MH, ODell JR, Mikuls TR, Buckner JH, Gregersen PK, Keating RM, Demoruelle MK, Deane KD, Holers VM, Norris JM. Evaluating associations of joint swelling, joint stiffness and joint pain with physical activity in first-degree relatives of patients with rheumatoid arthritis: Studies of the Aetiology of Rheumatoid Arthritis (SERA), a prospective cohort study. BMJ Open. 2021 09 14; 11(9):e050883.