The Physical Activity and Disability Survey - Revised (PADS-R): an evaluation of a measure of physical activity in people with chronic neurological conditions

Objective: To revise the Physical Activity Disability Scale (PADS) and to explore the acceptability and test-retest reliability of the revised measure, the PADS-R, in people with multiple sclerosis. Design: This study was conducted over three phases: (1) PADS-R questionnaire development including modification to the original PADS, field testing and refinement; (2) PADS-R scoring; (3) PADS-R acceptability and reliability assessment, where participants completed the PADS-R twice over the telephone, three days apart, and then answered a series of semi-structured questions on the instrument's acceptability. Subjects: Participants were recruited from the local Multiple Sclerosis Society, Stroke Foundation and Auckland District Health Board depending on the purpose of each phase: (1) PADS-R questionnaire development (n = 30, multiple sclerosis); (2) PADS-R scoring (n = 293, multiple sclerosis; and n = 83, stroke); and (3) PADS-R acceptability and reliability assessment (n 29, multiple sclerosis). Main measures: Physical Activity Disability Scale-Revised (PADS-R) Results: The PADS-R took approximately 20 minutes to administer and most (n = 25; 86%) participants reported it to be easy to understand and complete. All participants reported that it enabled them to give an accurate picture of their physical activities. In terms of test-retest reliability, the intraclass correlation coefficient was high (0.87 (95% confidence intervals (CI) 0.78, 0.96)), but the 95% limits of agreement were wide (+/- 1.13). When observations which potentially represented important changes in activity were excluded, these limits narrowed considerably (+/- 0.89). Conclusions: The PADS-R appears to be a conceptually and psychometrically sound measure of physical activity for people with chronic neurological conditions.