Reliability, validity and responsiveness of Brazilian version of QuickDASH.

Objective: To analyse the construct validity, test-retest reliability and responsiveness of the Brazilian version of Quick-DASH (QD-Br) in patients with upper limb disorders.

Method: Participants completed the full Brazilian DASH, the QD-Br and the SF-12 Brazil questionnaires at the beginning of treatment, after 48-72h and the after 2-12 months. Construct validity was analysed by Pearson's correlation coefficient (r). To evaluate the test-retest reliability we used the Intraclass Correlation Coefficient (ICC) and the Cronbach's alpha coefficient to test the internal consistency. Responsiveness was analysed by Standardized Response Mean (SRM) and Effect Size (ES). The Minimal detectable change (MDC) score was based upon calculations of the standard error of measurement (SEM), confidence interval of 95%.

Results: The construct validity presented strong direct correlation with the total QD-Br score and the Brazilian DASH (r = 0.91), a moderate inverse correlation between the total QD-Br score and the physical component of the SF- 12 Brazil (r = -0.55) and weak inverse correlation between the QD-Br and the mental component of SF-12 Brazil (r = -0.49). The ICC test-retest showed good reliability of 0.81 (0.72-0.87). QD-BR presented high responsiveness, with ES of 1.06 and SRM of 0.94. The MDC was 17.27 points.

Conclusion: These results provide evidence that the QD-Br was a valid, reliable and responsive instrument when utilized in patients with upper limb traumatic and no-traumatic disorders in the Brazilian population.