In Brief:
The psychometric properties of a new measure of functional status, the Pain Disability Questionnaire (PDQ), was evaluated in this study, and its validity and responsiveness were compared with traditional measures of functional status, such as the Oswestry, Million (VAS), and SF-36 instruments. Four groups of patients were used in this psychometric evaluation: an asymptomatic normative population (n = 50), an acute musculoskeletal disorder population (n = 52), a chronic disabled musculoskeletal disorder population (n = 230), and a heterogeneous pain population (n = 114). Results revealed the PDQ to have excellent psychometric properties, and it consistently demonstrated stronger correlation coefficients to a wide variety of physical and psychosocial measures of human function than other instruments. A factor analysis of the PDQ also revealed two factors: a Functional Status Component and a Psychosocial Component.
