Background: The purpose of this study was to develop a short,
reliable, and valid measure of physical function and symptoms related to
upper-limb musculoskeletal disorders by shortening the full, thirty-item DASH
(Disabilities of the Arm, Shoulder and Hand) Outcome Measure.
Methods: Three item-reduction techniques were used on the
cross-sectional field-testing data derived from a study of 407 patients with
various upper-limb conditions. These techniques were the concept-retention
method, the equidiscriminative item-total correlation, and the item response
theory (Rasch modeling). Three eleven-item scales were created. Data from a
longitudinal cohort study in which the DASH questionnaire was administered to
200 patients with shoulder and wrist/hand disorders were then used to assess
the reliability (Cronbach alpha and test-retest reliability) and validity
(cross-sectional and longitudinal construct) of the three scales. Results were
compared with those derived with the full DASH.
Results: The three versions were comparable with regard to their
measurement properties. All had a Cronbach alpha of =0.92 and an intraclass
correlation coefficient of =0.94. Evidence of construct validity was
established (r = 0.64 with single-item indices of pain and function). The
concept-retention method, the most subjective of the approaches to item
reduction, ranked highest in terms of its similarity to the original DASH.
Conclusions: The concept-retention version is named the QuickDASH.
It contains eleven items and is similar with regard to scores and properties
to the full DASH. A comparison of item-reduction approaches suggested that the
retention of clinically sensible and important content produced a comparable,
if not slightly better, instrument than did more statistically driven
Clinical Relevance: The QuickDASH is a more efficient version of the
DASH outcome measure that appears to retain its measurement properties.