WOrk-Related Questionnaire for UPper extremity disorders (WORQ-UP): Factor Analysis and Internal Consistency.

OBJECTIVE:To test a 17-item questionnaire, the WOrk-Related Questionnaire for UPper extremity disorders (WORQ-UP), for dimensionality of the items (factor analysis) and internal consistency. DESIGN:Cross-sectional study. SETTING:Outpatient clinic. PARTICIPANTS:A consecutive sample of patients (N=150) consisting of all new referral patients (either from a general physician or other hospital) who visited the orthopedic outpatient clinic because of an upper extremity musculoskeletal disorder. INTERVENTIONS:Not applicable. MAIN OUTCOME MEASURES:Number and dimensionality of the factors in the WORQ-UP. RESULTS:Four factors with eigenvalues (EVs) >1.0 were found. The factors were named exertion, dexterity, tools & equipment, and mobility. The EVs of the factors were, respectively, 5.78, 2.38, 1.81, and 1.24. The factors together explained 65.9% of the variance. The Cronbach alpha values for these factors were, respectively, .88, .74, .87, and .66. CONCLUSIONS:The 17 items of the WORQ-UP resemble 4 factors-exertion, dexterity, tools & equipment, and mobility-with a good internal consistency.