The association of fatigue, comorbidity burden, disease activity, disability and gross domestic product in patients with rheumatoid arthritis. Results from 34 countries participati... 由 Grøn, K, Ornbjerg, L, Hetland, M, Aslam, F, Khan, N, Jacobs, J, Henrohn, D, Rasker, J, Kauppi, M, Lang, H, Mota, L, Aggarwal, A, Yamanaka, H, Badsha, H, Gossec, L, Cutolo, M, Ferraccioli, G, Gremese, E, Bong Lee, E, Inanc, N, Direskeneli, H, Taylor, P, Huisman, M, Alten, R, Pohl, C