The Pedi-IKDC is an English-language, knee-specific, paediatric questionnaire used by orthopaedic surgeons around the world as a valuable patient-reported outcome measure (PROM). The objective of this study was thus to extend the applicability of the Pedi-IKDC to French-speaking Canadian patients, for both clinical practice and research, by developing a French-language cross-cultural adaptation of the original version.

The French adaptation of the Pedi-IKDC is valid and reliable for evaluating French-speaking children with knee conditions.

The Pedi-IKDC was translated to French by a panel of orthopaedic surgeons then back-translated by a professional translator. The original English version and the back-translation were compared to assess their similarity and confirm the faithfulness of the French translation. The validity of the French version was then tested at a major paediatric hospital in French-speaking Canada, in 203 children, including 163 with knee pain and 40 without knee symptoms. Internal consistency, construct validity, and discriminant capacity of the French version were assessed.

Internal consistency of the Pedi-IKDC adaptation was excellent (Cronbach's alpha, 0.934 in the knee-pain group). Construct validity was robust, with all nine hypotheses adapted from the original Pedi-IKDC article demonstrating strong (n=7) or moderate (n=2) correlations (p<0.001). The evaluation of discriminant capacity identified no statistically significant score differences according to most of the respondent characteristics (body mass index, age group, type of diagnosis, and type of treatment). However, scores differed significantly between females and males.

The French-language cross-cultural adaptation of the Pedi-IKDC obtained using a universally recognized method for translating PROMs demonstrated good performance, with psychometric properties similar to those of the original Pedi-IKDC and of its Danish, Italian, and Russian adaptations.

II.