TY - JOUR T1 - GRAPPA-OMERACT initiative to standardise outcomes in psoriatic arthritis clinical trials and longitudinal observational studies JF - Annals of the Rheumatic Diseases JO - Ann Rheum Dis SP - e23 LP - e23 DO - 10.1136/annrheumdis-2017-212004 VL - 77 IS - 5 AU - William Tillett AU - Ana-Maria Orbai AU - Alexis Ogdie AU - Ying Ying Leung AU - Vibeke Strand AU - Dafna D Gladman AU - Philip J Mease AU - Laura C Coates A2 - , Y1 - 2018/05/01 UR - http://ard.bmj.com/content/77/5/e23.abstract N2 - We read with interest the recent letter by Ramiro et al 1 reporting data from a systematic literature review on the measurement of enthesitis, dactylitis and nail disease in psoriatic arthritis (PsA) clinical trials. The authors highlight the great variety in the outcome measures chosen, cut points and the statistical analysis performed (percentage change, proportion resolved). We are pleased the authors have highlighted this problem and agree with their viewpoints on the clear lack of standardisation of domains and instruments in clinical trials evidenced by the data. Indeed this inconsistency of data reporting has led to significant heterogeneity in both physician-assessed and patient-reported outcomes particularly in the field of PsA. It is the domains of enthesitis, dactylitis, … ER -