Validity and Reliability of the Turkish Version of the DASH-TR Questionnaire in Rheumatoid Arthritis Patients, Based on Rasch Analysis.

Aim: This study aimed to examine the validity and reliability of the Turkish version of the Disabilities of the Arm, Shoulder and Hand Problems (DASH-TR) questionnaire in rheumatoid arthritis (RA) using the Rasch analysis.
Method: A total 97 individuals (13 men, 84 women; mean age:51.99 ± 11.12 years, range: 20-65 years) diagnosed as having RA according to the criteria of the American College of Rheumatology were included. The functional status of the upper extremities was evaluated with the DASH-TR questionnaire, patient global health with a visual analog scale (VAS), disease activity with Disease Activity Score 28-C-reactive protein (DAS28-CRP), and disability with Health Assessment Questionnaire (HAQ). DASH-TR was applied to the patients with RA who did not receive any treatment for test-retest at 1-week intervals. DASH-TR results were analyzed using the Rasch analysis.
Results: In the sample of patients with RA, it was determined that the DASH-TR scale did not provide a unidimensional structure and the items were collected in two dimensions. The first 20 items and the last nine items were differentiated in the two-dimensional structure, and the factor load of m21 was low. Person separation index was obtained as 0.948. Internal consistency reliability was quite high. A significant positive correlation was found between the DASH-TR and VAS, DAS28 and HAQ. There was excellent test-retest reliability according to the intra-class correlation coefficient (0.921, 95% CI 0.882-0.947; P < 0.001).
Conclusion: The DASH-TR is a reliable and valid questionnaire and can be used for measurement of functional status of the upper extremities in RA.
(© 2022 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.)