ABSTRACT
OBJECTIVE: To establish a questionnaire for quantification of hand involvement in osteoarthritis (OA) of the hands and rheumatoid arthritis (RA) meeting daily routine requirements. PATIENTS AND METHODS: The smallest number of questions of the modified score for the assessment and quantification of chronic rheumatic affections of the hands (M-SACRAH) providing reasonable reliability was identified by factor analysis and calculating Cronbach's alpha, subsequently resulting in a five-item scale, the short form-SACRAH (SF-SACRAH), which was then administered to 176 RA and 71 hand-OA (HOA) patients simultaneously with the M-SACRAH. Additionally, patient's satisfaction (PatSAT) with disease status was assessed (according to the Austrian school marking system from 1 to 5). Gamma was calculated to assess the agreement of the SF-SACRAH with the M-SACRAH and between the single corresponding questions of different formats. The Wilcoxon rank test was applied to estimate the relationship between PatSAT and the SF-SACRAH. RESULTS: Alpha for the SF-SACRAH in 176 RA and 71 HOA patients amounted to 0.869 and to 0.897, respectively, indicating high internal consistency. In both patient groups the SF-SACRAH was found to be significantly correlated to the M-SACRAH (both P(s)<0.01). Agreement between the corresponding questions of both scales was significant in both patient groups by calculating gamma (average gamma 0.683 in HOA and 0.847 in RA). PatSAT and SF-SACRAH values were highly significantly correlated (P<0.001) proving the score's external validity. CONCLUSION: The SF-SACRAH proved to be a brief and practicable tool to assess hand involvement in OA and RA meeting the requirements of daily routine.
