Use PROMs adapted for children and avoid PROMs developed for adults. Translation and Validation of paediatric IKDC subjective knee form in Lithuanian Children and Adolescents with Knee Disorders

Abstract Background/Purpose: The usage of children adapted PROMs is encouraged. This study is designed to translate and adapt the Pedi-IKDC for Lithuanian children with knee disorders and evaluate the psychometric properties of the new Pedi-IKDC version. Methods: The translation process was performed under international guidelines. Patients aged 11-17 years with various knee disorders participated at three surveys and completed the Pedi-IKDC, Lysholm and PedsQL questionnaires. The internal consistency and reproducibility were determined by Cronbach alpha (a) statistics and intraclass correlation coefficient (ICC) respectively. For evaluation of reliability the standard error of measurement (SEM) and the smallest detectable change (SDC) were estimated. Regarding criterion validity, the Pearson correlations were assessed between Pedi-IKDC and Lysholm, PedsQL scores. The responsiveness to change was checked by calculating the effect size (ES) and standardized response mean (SRM). The floor and ceiling effects were verified for content validity. Results: The Cronbach alpha (a) was 0.91 for overall score, 0.75 for symptoms and 0.92 for sport/function component of the score. The ICC for overall scores was 0.98 and from 0.87 to 0.98 for separate questions. SEM was 2.97 and SDC – 8.23. Moderate correlations (0.8> r > 0.5) were found to Lysholm and PedsQL physical functioning domain score, weak (0.5>r > 0.2) - to overall PedsQL score. Floor and ceiling effects were - 3,3%, and 1,6% respectively. The ES was 1,98 and SRM- 1,72. Conclusions: The Lithuanian Pedi-IKDC version is suitable measurement tool to assess outcomes within paediatric population with different knee disorders. All the psychometric properties demonstrated acceptable results.