Incidence and prevalence of psoriatic arthritis in Denmark: a nationwide register linkage study by Egeberg, A, Kristensen, LE, Thyssen, JP, Gislason, GH, Gottlieb, AB, Coates, LC, Jullien, D, Gisondi, P, Gladman, DD, Skov, L, Mallbris, L

Prevalence of psoriatic arthritis in patients with psoriasis: A systematic review and meta-analysis of observational and clinical studies by Alinaghi, F, Calov, M, Kristensen, LE, Gladman, DD, Coates, LC, Jullien, D, Gottlieb, AB, Gisondi, P, Wu, JJ, Thyssen, JP, Egeberg, A