Reliability and validity of modified western ontario and mcmaster universities osteoarthritis index gujarati version in participants with knee osteoarthritis

Abstract

BACKGROUND: Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) is the most widely used condition-specific self-reported multidimensional instrument for the assessment of hip or knee osteoarthritis (OA).OBJECTIVE: The objective of this study is to translate and to investigate the reliability and validity of modified WOMAC (mWOMAC) Gujarati version in participants with knee OA.MATERIALS AND METHODOLOGY: The Indian version mWOMAC English questionnaire was translated into Gujarati with forward and backward method, and its psychometric properties were analyzed on 230 Gujarati-speaking participants with knee OA (mean age = 58.4 years). The visual analog scale (VAS) for pain and handheld dynamometer (HHD) for isometric quadriceps strength along with mWOMAC was recorded twice within 2 days, and data were used to assess the reliability and convergent validity.RESULTS: The mWOMAC Gujarati version questionnaire was internally consistent with Cronbach's alpha 0.936 (test), 0.940 (retest), respectively. Test-retest reliability was analyzed using mixed model intraclass correlation coefficient (ICC) and found satisfactory with ICCs of 0.986. Convergent validity was analyzed using Pearson's correlation coefficient between mWOMAC and VAS (P < 0.05, r = 0.716); mWOMAC and HHD (P < 0.05; r = −0.915) and significant correlation was found.CONCLUSION: The mWOMAC Gujarati version is a reliable and valid self-rated clinical instrument for the assessment of symptoms and function in OA knee.