Aouad K, Moysidou G, Rakotozafiarison A, et al. - Multiple outcome measures can be employed to assess disease activity in psoriatic arthritis (PsA), which is a multidimensional inflammatory disease. The first core domain set in PsA was proposed by the OMERACT in 2006. Researchers herein assessed outcome measures obtained in recent PsA registries or longitudinal cohorts. A systematic literature review, performed in Pubmed Medline yielded 673 articles; 73 of these were included in the analysis, reporting on 27 registries/cohorts. Overall, they included 16,183 patients, with a mean of 599 per study; 51% were men, weighted mean age was 49.7±9.3 years and weighted mean disease duration was 6.8±0.2 years. Great heterogeneity was observed in data collection in PsA, reflecting the necessity for international consensus on outcome measures. They obtained 58 different outcome measures. In 20/27 (74%) registries, disease activity composite scores were utilized through 8 different scores (most frequently Minimal Disease Activity: 41%, DAS28: 33% and DAPSA: 30%). Among the domains of PsA, 26/27 (96%) registries described joint involvement (through the 66/68 joint count: 85%) and 93% described skin psoriasis (through PASI: 72%), whereas enthesitis, dactylitis and axial involvement were less often described (respectively, 77%, 74% and 52%). In addition, 22/27 (82%) studies documented HAQ; patient global assessment (70%) and pain (63%) were the other frequently reported PROs.