Translation, cross-cultural adaptation and psychometric properties of the Urdu version of knee injury and osteoarthritis outcome score questionnaire for Pakistani population

BACKGROUND: Knee injury and osteoarthritis outcome score questionnaire is a widely used tool for measuring short and long-term patient-relevant outcomes following knee injury. KOOS is neither translated nor examined for psychometric properties before. Therefore, the aim of this study was to translate, culturally adapt and check the psychometric properties of the KOOS in Urdu. METHODOLOGY: The translation and cultural adaptation was performed according to pre-defined guidelines. A total of 117 participants (54 males and 63 females) were recruited. The study had two steps: 1) Translation and cultural adaptation 2) Reliability and validity testing. The reliability (test-retest and internal consistency at (95% confidence interval) as well as the validity (Convergent validity) of final Urdu version of KOOS was tested. RESULTS: For all five domains, the KOOS Urdu version (KOOS-U) has demonstrated high test-retest reliability ICC = 0.90–0.96(CI = 95%). For all domains, the internal consistency was determined to be excellent (α = 0.82–0.96). There were no floor or ceiling impacts noted. Convergent validity was found to be good, as measured by Pearson’s correlation coefficient. The findings revealed a strong negative association between the KOOS-U (QOL and pain) and the NPRS. And there was a low to high positive correlation between five KOOS-U domains and all SF-12 domains, i.e., there was a significant positive correlation between the pain domains of both KOOS and SF-12 with the r = 0.87(p < 0.05). CONCLUSION: The Urdu version of KOOS is a valid, reliable, and responsive instrument to assess functional disability of patients with Knee Osteoarthritis with excellent psychometric properties.