Open AccessA self‐administered rheumatoid arthritis disease activity index (RADAI) for epidemiologic research
Author(s) -
Stucki Gerold,
Liang Matthew H.,
Stucki Susanne,
Brühlmann Pius,
Michel Beat A.
Publication year - 1995
Publication title -
arthritis & rheumatism
Language(s) - English
Resource type - Journals
eISSN - 1529-0131
pISSN - 0004-3591
DOI - 10.1002/art.1780380612
Subject(s) - medicine , rheumatoid arthritis , rheumatology , cronbach's alpha , construct validity , physical therapy , psychometrics , clinical psychology
Objective . To examine the psychometric properties and construct validity of a self‐administered Rheumatoid Arthritis Disease Activity Index (RADAI). Methods . Five items of the Rapid Assessment of Disease Activity in Rheumatology (RADAR) questionnaire were aggregated into the RADAI and assessed for their factor loading, internal consistency, and construct validity. Results . In 55 patients with RA, the RADAI had a high internal consistency (Cronbach's alpha = 0.91) and correlated with physician's assessment of disease activity (r = 0.54, P < 0.01), the swollen joint count (r = 0.54, P < 0.01), and the C‐reactive protein value (r = 0.43, P < 0.01). Conclusion . The RADAI is a highly reliable and valid self‐administered measure of disease activity for clinical, health services, and epidemiologic research. Its sensitivity to change in longitudinal studies needs further study.