[Transcultural adaptation and validation of the DASH questionnaire in Mexican healthy volunteers and patients with neurogenic disorders of the upper extremity].

Background: The Disability of the Arm, Shoulder and Hand (DASH) questionnaire assesses the impact of upper extremity disorders on quality of life. However, its use in the Mexican population has not been formally validated.

Objective: To conduct a cultural adaptation and validation of the DASH questionnaire to evaluate the perspective of patients with neurogenic disorders of the upper extremity regarding the impact on their quality of life.

Method: We performed an adaptation of the Spanish version of the DASH questionnaire to the Mexican vocabulary and applied it to 478 volunteers. Ceiling effect, floor effect, item-total correlation, descriptive statistics of items and total score, internal consistency, precision, cross-sectional and longitudinal validity were estimated by comparing healthy controls and affected individuals with different disability levels.

Results: Our DASH questionnaire version was equivalent to those previously approved and showed homogeneity of the items with respect to the total value of the questionnaire (Cronbach's alpha > 0.96). In addition, it showed an accuracy of 7.25 points and the crosssectional and longitudinal validity was documented with significant differences between groups and subgroups with distinct disability levels.

Conclusions: The DASH questionnaire can be used with a high level of confidence in the Mexican population.