Concurrent validity study of QuickDASH with respect to DASH in patients with traumatic upper extremity amputation.

BACKGROUND

The Disability of the Arm, Shoulder and Hand Outcome Measure (DASH) is a validated patient-reported outcome measure (PROM) for many upper extremity musculoskeletal disorders. In patients with severe traumatic conditions, limited evidence exists regarding the equivalence between DASH and its shortened version, QuickDASH, which is more feasible in clinical practice. The rationale of this study was to analyze the concurrent validity of QuickDASH with respect to DASH in patients with traumatic upper extremity amputation.

METHODS

This study is based on a consecutive cohort of traumatic upper extremity amputation patients treated with replantation or revision (completion) amputation at Tampere University Hospital between 2009 and 2019. We estimated the concurrent validity of QuickDASH with respect to DASH by correlation coefficients, mean score differences, Bland-Altman plots, and distribution density. Additionally, we assessed internal reliability with Cronbach's alpha coefficients and item-total correlations.

RESULTS

We found a very strong linear correlation between DASH and QuickDASH scores (r = 0.97 [CI 95% 0.97-0.98], p < 0.001). The mean difference between DASH and QuickDASH was minor (MD = -1, SD 4 [CI95% from -1 to 0] p = 0.02). The mean sub-score for the activity domain was higher for QuickDASH than DASH (MD = -3 [CI95% from -4 to -3] p < 0.000) and lower for the symptom domain (MD = 7 [CI95% from 6 to 9] p < 0.000). The Bland and Altman plot showed good agreement between DASH and QuickDASH scores, but there was measurement error in QuickDASH with high scores (r = -0.20, [CI95% from -0.31 to -0.09], p = 0.001).

CONCLUSION

QuickDASH demonstrates higher total scores than the full DASH and emphasizes rating of activity over symptoms. Still, on average the differences in total scores are likely less than the MCID of DASH, and consequently, this study shows that QuickDASH can be recommended instead of the full DASH when assessing a traumatic condition.

TRIAL REGISTRATION

Retrospectively registered.