TY - JOUR T1 - The development of candidate composite disease activity and responder indices for psoriatic arthritis (GRACE project) JF - Annals of the Rheumatic Diseases JO - Ann Rheum Dis SP - 986 LP - 991 DO - 10.1136/annrheumdis-2012-201341 VL - 72 IS - 6 AU - Philip S Helliwell AU - Oliver FitzGerald AU - Jaap Fransen AU - Dafna D Gladman AU - Gerald G Kreuger AU - Kristina Callis-Duffin AU - Neil McHugh AU - Philip J Mease AU - Vibeke Strand AU - Robin Waxman AU - Valderilio Feijo Azevedo AU - Adriana Beltran Ostos AU - Sueli Carneiro AU - Alberto Cauli AU - Luis R Espinoza AU - John A Flynn AU - Nada Hassan AU - Paul Healy AU - Eduardo Mario Kerzberg AU - Yun Jong Lee AU - Ennio Lubrano AU - Antonio Marchesoni AU - Helena Marzo-Ortega AU - Giovanni Porru AU - Elvia G Moreta AU - Peter Nash AU - Helena Raffayova AU - Roberto Ranza AU - Siba P Raychaudhuri AU - Euthalia Roussou AU - Raphael Scarpa AU - Yeong Wook Song AU - Enrique R Soriano AU - Paul P Tak AU - Ilona Ujfalussy AU - Kurt de Vlam AU - Jessica A Walsh Y1 - 2013/06/01 UR - http://ard.bmj.com/content/72/6/986.abstract N2 - Objective To develop new composite disease activity indices for psoriatic arthritis (PsA). Methods Data from routine clinic visits at multiple centres were collected in a systematic manner. Data included all domains identified as important in randomised controlled trials in PsA. Decisions to change treatment were used as surrogates for high disease activity. New indices were developed by multiple linear regression (psoriatic arthritis disease activity score: PASDAS) and empirically, utilising physician-defined cut-offs for disease activity (arithmetic mean of desirability functions: AMDF). These were compared with existing composite measures: Composite Psoriatic arthritis Disease Activity Index (CPDAI), Disease Activity for PSoriatic Arthritis (DAPSA), and Disease Activity Score for rheumatoid arthritis (DAS28). Results 161/503 (32%) subjects had treatment changes. Although all measures performed well, compared with existing indices, PASDAS was better able to discriminate between high and low disease activity (area under receiver operating curves (ROC)) curve with 95% CI: PASDAS 0.773 (0.723, 0.822); AMDF 0.730 (0.680, 0.780); CPDAI 0.719 (0.668, 0.770); DAPSA 0.710 (0.654, 0.766); DAS28 0.736 (0.680, 0.792). All measures were able to discriminate between disease activity states in patients with oligoarthritis, although area under the receiver operating curves (AUC) were generally smaller. In patients with severe skin disease (psoriasis area and severity index >10) both nonparametric and AUC curve statistics were nonsignificant for all measures. Conclusions Two new composite measures to assess disease activity in PsA have been developed. Further testing in other datasets, including comparison with existing measures, is required to validate these instruments. ER -