Disabilities of the arm, shoulder, and hand - DASH: análise da estrutura fatorial da versão adaptada para o português

Abstract

Disabilities of the Arm, Shoulder and Hand (DASH) is a tool that assesses function and symptoms in the upper limbs from the patient's perspective. It is an instrument that evaluates the upper limb as a functional unit, regardless of the affliction or its location. It has been translated into a number of languages and has proven to be valid and reliable. It has also been used as a function measure in clinical outcome studies. Inter and intra-examiner reliability in patients with rheumatoid arthritis constituted the psychometric properties analyzed. The present study analyzed the behavior of the items on the translated and validated Portuguese version of DASH in a sample composed of patients with chronic or acute illness in the upper limb or limbs. A methodological study was carried out on a sample of 309 patients with repetitive strain injury or previous fractures, constituting two sub-samples. Principal component factorial analysis and discriminative factorial analysis were performed. The sub-samples presented significant differences in average scores regarding gender, age, working condition and location of injury. The KMO (Kaiser-Meyer-Olkin) Test and Bartlett Test (Bartlett Test of Sphericity) showed adequate adaptation of the data to the factorial analysis, which identified 3 factors with Cronbach alphas between 0.77 and 0.94, explaining 59% of the variance in the overall sample. Strong positive and negative correlations were observed among the items of the instrument. The discriminative analysis adequately classified 93% of the patients regarding group of origin and identified eleven items with a discriminative power between groups of individuals who reported symptoms and function (physical dimension). In the present study, DASH proved to be a valid, reliable measure in the identification of different degrees of function and diagnostic groups, enabling discrimination and comparative observation of the behavior of the items in the sub-samples studied.