The validity and reliability of the Turkish version of the Rheumatoid and Arthritis Outcome Score (RAOS) in patients with rheumatoid arthritis

The goal of our study was to develop a Turkish version of the Rheumatoid and Arthritis Outcome Score (RAOS) in patients with rheumatoid arthritis (RA) and to assess its reliability, validity, and sensitivity to change. The Turkish version of RAOS was developed according to cross-cultural guidelines by using the “translation–back translation” method. Fifty-eight patients with RA were assessed with it. To assess its validity, patients were also evaluated with Turkish versions of the Health Assessment Questionnaire, five subscales of Arthritis Impact Measurement Scales, and the Rheumatoid Arthritis Quality of Life questionnaire. Test–retest reliability of the RAOS questionnaire was calculated on 58 patients within 1 week. Construct validity was investigated with use of Spearman’s rank correlation coefficient. Test–retest reliability was assessed with use of the intraclass correlation coefficient (ICC) and Cronbach’s alpha score. Sensitivity to change after the 4-week home-based exercise program was evaluated with paired t test comparisons. The Turkish version of the RAOS met set criteria of reliability and validity. The random ICC for the five subscales ranged from 0.76 to 0.94. Interitem correlation measured by Cronbach’s alpha ranged from 0.81 to 0.94. Correlations were found between RAOS subscales and all of the evaluation parameters (p < 0.01). RAOS subscales showed significant improvements after the 4-week home exercise program except for the symptom and quality of life subscales (p < 0.05). The effect sizes were ranged from 0.20 to 0.37 and were considered small. The results of this study showed that the Turkish version of RAOS was reliable, valid, and responsive in patients with rheumatoid arthritis.