Arthritis & Rheumatism, Volume 63,
November 2011 Abstract Supplement
Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Chicago, Illinois November 4-9, 2011.
Reproducibility of Composite Scores: Disease Activity 28-Joints Score, Simplified Disease Activity Score and Clinical Disease Activity Score In the Evaluation of Rheumatoid Arthritis(Ra) Disease Activity: Pursuit for A Gold Standard.
Guedes1, Lissiane K. N., Ribeiro2, Ana C. M., Moraes2, Julio C. B., Saad3, Carla G.S., Aikawa3, Nadia E., Neto4, Eduardo F. Borba, Pasotto2, Sandra
University of Sao Paulo, Sao Paulo, Brazil
Faculdade de Medicina da Universidade de São Paulo, Sao Paulo, Brazil
Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, Brazil
Universidade de São Paulo, Sao Paulo, Brazil
to evaluate the reproducibility of the different composite indexes of evaluation of disease activity: DAS28 with 3 or 4 variables, SDAI and CDAI in an extreme clinical set-up designed to test the reproducibility of these tools.
10 different physicians assessed classical parameters of disease activity in 340 adult patients with RA at baseline and after 21 days. The physicians were not uniformly familiar with the instruments; five applied these tools on regular basis and five, although experienced rheumatologists, were less familiar with these instruments. Patients were randomly allocated to each physician at baseline and after 21 days in such a way that less than 5% of the patients were assessed by the same physician at the two visits. No physician had acccess to the first evaluation. Acute-phase reactants were collected at baseline and after 21 days. All patients answered a YES/NO question regarding changes in the disease activity comparing their clinical status at baseline and after the 21 days. An affirmative answer or therapeutic changes, presence of infections, parenteral infusions or therapeutic intra-articular injection or arthrocenthesis during the 21 days of the study implied exclusion from the study.
Data from 319 patients were analysed (failure to attend the second visit or incomplete laboratory data). The intraclass correlations between the different indexes were DAS28(4V)=0.681 (IC95% 0.6150.737); DAS28(3V)=0.668 (IC95% 0.6000.726); SDAI=0.601 (IC95% 0.5240.668);CDAI(4V)=0.587 (IC95% 0.5090.656) showing a similar intraclass reproducibility for all indexes with correlation coefficients between 0.5 and 0.7. Remarkably patient dependent outcomes (PGHA, pain and tender joints) did not change. After 21 days a statistically significant reduction in DAS28 was observed 3.68 (1.37) vs. 3.51(1.39, p=0.01)) but the difference 0.17 was well below clinical meaningful values. Interestingly the difference was only in the physician-dependent outcomes: number of swollen joints and global health assessment (IGHA); ESR/CRP values did not change. DAS 28 showed a slightly better performance also suggested by Bland-Altman graphics.
Reproducibility of the different composite scores was adequate, despite the most unfavorable artificial set-up of this study. DAS28 seems to perform slightly better.
To cite this abstract, please use the following information:
Guedes, Lissiane K. N., Ribeiro, Ana C. M., Moraes, Julio C. B., Saad, Carla G.S., Aikawa, Nadia E., Neto, Eduardo F. Borba, et al; Reproducibility of Composite Scores: Disease Activity 28-Joints Score, Simplified Disease Activity Score and Clinical Disease Activity Score In the Evaluation of Rheumatoid Arthritis(Ra) Disease Activity: Pursuit for A Gold Standard. [abstract]. Arthritis Rheum 2011;63 Suppl 10 :1890