Cross‐cultural adaptation and initial evaluation of selected measurement properties of the simplified chinese version of the knee injury and osteoarthritis outcome score joint replacement in patients with knee osteoarthritis

Purpose This study aimed to translate and culturally adapt the knee injury and osteoarthritis outcome score joint replacement (KOOS‐JR) into simplified Chinese and provide an initial evaluation of selected measurement properties in patients with knee osteoarthritis (OA) scheduled for total knee replacement (TKR). Methods Eighty‐five patients completed the simplified Chinese KOOS‐JR and International Knee Documentation Committee (IKDC) at baseline, and clinically stable participants repeated the KOOS‐JR after 10–14 days. Selected properties included supervised data completeness, floor and ceiling effects, provisional internal consistency, test‐retest reliability, measurement error and construct validity. Results All 85 participants completed baseline and retest assessments. No floor or ceiling effects were observed. Cronbach's alpha was 0.849 at baseline and 0.816 at retest. intraclass correlation coefficient (A,1) was 0.791 (95% CI, 0.695–0.859). The mean test‐retest difference was −0.39 points, with an individual‐level smallest detectable change of 11.69 points. KOOS‐JR and IKDC scores were strongly correlated ( r s = 0.766; 95% CI, 0.646–0.850; p < 0.001). Conclusion The simplified Chinese KOOS‐JR showed reasonably stable test‐retest performance and initial supportive construct validity in this preoperative TKR cohort. Internal‐consistency evidence remains provisional because structural validity was not assessed. Further studies should evaluate structural validity, measurement invariance, responsiveness and practical burden. Level of Evidence N/A.