Purpose: To cross-culturally adapt and validate the International Knee Documentation Committee Subjective Knee Form to Simplified Chinese (SC-IKDC-SKF).
Methods: The original version was translated and cross-culturally adapted into Simplified Chinese according to standard guidelines. A total of 103 patients enrolled in our research. Each participant was asked to complete three instruments including the SC-IKDC-SKF, the Lysholm knee score, and the Short Form-36 (SF-36). Each participant was asked to complete the SC-IKDC-SKF twice with an interval of 7 days. A portion of the participants (n = 51) finished the SC-IKDC-SKF a third time with an interval of 12 months after arthroscopic treatment. Psychometric assessments included internal consistency, test-retest reliability, content and construct validity, and responsiveness.
Results: Strong internal consistency was proved with Cronbach's α = 0.92. The intraclass correlation coefficient reached 0.94, indicating high test-retest reliability. No ceiling or floor effect was observed. Compared with the Lysholm knee score and the subscales of SF-36, good convergent and divergent validity of the SC-IKDC-SKF were demonstrated. The standard response mean was 2.39 and the effect size was 1.33, indicating high responsiveness.
Conclusions: The SC-IKDC-SKF was demonstrated to be a reliable, valid and responsive instrument for evaluating knee functions and symptoms of patients with knee pathology in mainland China.
Level of evidence: II.
Keywords: Instrument; International Knee Documentation Subjective Knee Form; Knee; Simplified Chinese; Validation.