RÉSUMÉ
PURPOSE: To comparatively evaluate the reliability and validity of the Western Ontario and McMaster (WOMAC) and the Lequesne algofunctional indices in Greek patients with hip or knee osteoarthritis (OA). METHODS: The Greek versions of WOMAC LK 3.1 and Lequesne indices were administered to 97 outpatients with OA. Internal consistency reliability was assessed by Cronbach's alpha and item-scale correlations. Test-retest reliability was examined with intraclass correlations. Patients were also asked to complete the Short Form 36 (SF-36) and a Visual Analog Scale capturing strength of pain, in order to assess construct validity. Additional demographic and clinical data were also recorded to evaluate further associations. RESULTS: Cronbach's alpha values of the WOMAC ranged between 0.92 and 0.98 for hip and 0.89-0.97 for knee OA. The respective values for Lequesne were 0.63-0.74 and 0.74-0.80. Item-scale correlations confirmed the superiority of WOMAC with respect to internal consistency reliability. Intraclass correlations were 0.79-0.97 and 0.57-0.98 for hip and 0.86-0.97 and 0.82-0.97 for knee OA, for WOMAC and Lequesne, respectively. The two indices showed high correlations with comparable subscales of SF-36 and the Visual Analog Scale. Significant relationships were identified for age, body mass index, duration of disease, duration of stiffness and radiographic classification. CONCLUSIONS: Our findings, in samples of knee and hip OA patients, indicate that the WOMAC index demonstrates better internal consistency reliability than the Lequesne counterpart, as well as equivalent test-retest reliability and construct validity.
