Secondary Outcomes
Questionnaires. The 24-item disease specific Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was used to assess pain, stiffness, and physical function in the
primary OA joint over the previous 48 hours. This measure has been validated with respect to reliability, face validity, content validity, construct validity, and responsiveness for people with OA of the hip or knee.20 Health-related quality of life over the previous week was assessed with the 15-item Assessment of Quality of Life scale.21 This scale has been validated for use in the general population.Physical activity levels over the previous week were assessed with the
Physical Activity Scale for the Elderly (PASE) (with supervised aquatic physical therapy sessions excluded from the analyses to accurately measure independent activity). The PASE demonstrated good test-retest reliability,convergent validity, and construct validity in older adults with knee pain.