Section of Sports Traumatology, Orthopedic Surgery Department, Bispebjerg and Frederiksberg Copenhagen University Hospital, Copenhagen, Denmark
Section of Sports Traumatology, Orthopedic Surgery Department, Bispebjerg and Frederiksberg Copenhagen University Hospital, Copenhagen, Denmark.
Br J Sports Med. 2022 Nov;56(22):1284-1291. doi: 10.1136/bjsports-2021-105311. Epub 2022 Aug 9.
Knee injury and Osteoarthritis Outcome Score (KOOS)-Child is a modification of the adult KOOS aiming to evaluate knee injury, including ACL deficiency. However, the measurement properties of KOOS-Child have not been assessed in a cohort of children with ACL deficiency. We aimed to study the structure of KOOS-Child using modern test theory models (Rasch analysis and confirmatory factor analysis (CFA)).
Data were collected prospectively in a cohort of children with ACL deficiency at three time points: before-and-after ACL surgery, and at 1-year follow-up. For each subscale, structural validity through the fit of a CFA model was evaluated for 153 respondents. Modification indices were examined to find the model of best fit, confirmed using Rasch analysis. Responsiveness was reported for each subscale. Reliability was calculated for each item. Floor and ceiling effects, and Person-item distribution were reported.
All subscales showed inadequate fit to a unidimensional CFA model. Rasch analysis confirmed these results. Adjusting the subscales improved model fit, although this was still quite poor, except for the quality of life subscale. With one exception, all items demonstrated ceiling effects. Person-item distribution confirmed this. Due to lack of fit, reliability was not reported. All subscales were able to detect change from baseline to 1-year follow-up.
KOOS-Child exhibits inadequate measurement properties in its current form for children with ACL deficiency. Suggestions to make the subscales fit the models better and improve accuracy of KOOS-Child are presented. However, the large ceiling effects observed may reduce sensitivity and induce type 2 errors.
膝关节损伤和骨关节炎结局评分（KOOS）-儿童版是对成人 KOOS 的修订版，旨在评估膝关节损伤，包括 ACL 缺失。然而，在 ACL 缺失的儿童队列中，尚未对 KOOS-儿童的测量性能进行评估。我们旨在使用现代测试理论模型（Rasch 分析和验证性因子分析（CFA））来研究 KOOS-儿童的结构。
前瞻性地在 ACL 缺陷儿童队列中收集数据，共三个时间点：ACL 手术前后和 1 年随访。对于每个子量表，通过对 153 名受访者的 CFA 模型拟合来评估结构效度。检查修正指数以找到最佳拟合模型，使用 Rasch 分析进行验证。报告每个子量表的反应性。为每个项目计算可靠性。报告地板和天花板效应以及人员-项目分布。
所有子量表的一维 CFA 模型拟合均不理想。Rasch 分析证实了这些结果。调整子量表可以改善模型拟合，但除生活质量子量表外，拟合仍然很差。除一项外，所有项目均显示出天花板效应。人员-项目分布证实了这一点。由于拟合不佳，未报告可靠性。所有子量表均能从基线到 1 年随访检测到变化。
ACL 缺失儿童的 KOOS-儿童在其当前形式下表现出测量性能不足。提出了改进子量表拟合模型和提高 KOOS-儿童准确性的建议。然而，观察到的较大天花板效应可能会降低敏感性并引起第二类错误。
