Cross-cultural adaptation and validation of Korean Western Ontario and McMaster universities (WOMAC) and Lequesne Osteoarthritis Indices for ClinicalResearch

Objective: Our aims were to translate WOMAC and Lequesne osteoarthritis (OA ) indices into Korean (KWOMAC, KLequesne) and confirm their reliability, va lidity, and responsiveness. Design: The WOMAC and Lequesne indices were translated into Korean by three translators and translated back into English by three different translator s. Fifty consecutive patients with CA were asked to rate the comprehensibil ity of the questions on a 4-point scale. The comprehensibility (responding with 'good' and 'very good') ranged from 78% to 99%. Test-retest was perfor med in another 47 patients with knee OA. The final 53 patients with knee OA , within the context of a clinical trial of two non-steroidal antiinflammat ory drugs for 4 weeks, were studied to assess the internal consistency, con struct validity, and responsiveness of the Korean versions. Results: The test-retest reliability of the KWOMAC 3 subscales and the KLeq uesne yielded intraclass correlation coefficients of 0.79-0.89 and 0.87. Th e Cronbach standardized alphas were 0.81-0.96 and 0.75, respectively. For t he construct validity, the correlation coefficients of both the KWOMAC subs cales and the KLequesne with patient pain assessment and patient global ass essment were between 0.30 and 0.70 and the KWOMAC subscales correlated with the KLequesne (0.41-0.55). For responsiveness, the KWOMAC and KLequesne sc ores significantly improved by 4-week post-treatment compared with pre-trea tment; effect size values were between 0.41 and 0.69 for the KWOMAC subscal es and 0.70 for the KLequesne; and the relative efficiency values of the KW OMAC subscales vs the KLequesne were between 0.87 and 0.90. Conclusions: The reliability, validity, and responsiveness of the KWOMAC an d the KLequesne are confirmed. (C) 2001 OsteoArthritis Research Society Int ernational.