2.4.2. Disability
The T-WOMAC was used as a self-reported questionnaire for patients with hip or knee OA. It was a 24-item questionnaire and consisted of three subscales: pain, stiffness and physical function.
The WOMAC used a visual analog scale (0–10), 0 meaning ‘‘totally unaffected’’ and 10meaning ‘‘totally affected’’. In this study we used the third part, the physical functioning subscale, as the outcome measure. There were 17-items in this subscale; a higher score means more severe disability. The reliability and validity of WOMAC has been well established (Cronbach’s a = 0.70–0.93), including the use of subscales separately (Bellamy et al., 1988).