INTRA- AND INTER-OBSERVER AGREEMENT OF PROXIMAL HUMERAL FRACTURES CLASSIFICATIONS IN ADULTS

ABSTRACT Objective: Evaluating intra- and inter-observer agreement of the Neer, AO, and AO/OTA proximal humerus fractures classification systems in adults. Methods: In total, 100 X-rays of patients with proximal humerus fractures were selected according to the inclusion and exclusion criteria established in this study. They were evaluated by four evaluators with different levels of expertise. The evaluation was performed at two distinct moments, with an interval of 21 days between each analysis. Images were randomized for the second evaluation by a researcher who did not participate in the image selection process. A Fleiss Kappa test was performed to evaluate intra- and inter-observer agreement. Results: We observed a substantial agreement with k = 0.669, k = 0.715, and k = 0.780 for the Neer, AO, and AO/OTA classification systems, respectively. Conclusion: In the second evaluation, intra-observer agreement improved. In the first evaluation, we obtained values of k = 0.724, k = 0.490, and k = 0.599 for the evaluation of the Neer, AO, and AO/OTA classifications. In the second evaluation, the values k = 0.759, k = 0.772, and k = 0.858. Therefore, the evaluations went from moderate to substantial for the AO classification and from moderate to practically perfect for the AO/OTA classification. The level of inter-observer agreement was substantial (0.61-0.80), with k = 0.669, k = 0.715, and k = 0.780 for the Neer, AO, and AO/OTA classifications, respectively. Level of Evidence III, Cross-Sectional Observational Study.

摘要
研究目的：评估成人肱骨近端骨折Neer分型、AO分型及AO/OTA分型的观察者内部一致性与观察者间一致性。
方法：本研究依据既定纳入与排除标准，共选取100例肱骨近端骨折患者的X线影像。由4名专业水平各异的评估者开展阅片评估，评估分为两个独立阶段，两次评估间隔时长为21天。由未参与影像遴选流程的研究人员对第二次评估所用影像进行随机化处理。采用弗莱斯Kappa检验（Fleiss Kappa test）评估观察者内部及观察者间一致性。
结果：Neer分型、AO分型及AO/OTA分型的Kappa值分别为0.669、0.715和0.780，均达到显著一致性水平。
结论：第二次评估中，观察者内部一致性有所提升。首次评估时，Neer、AO及AO/OTA分型的Kappa值分别为0.724、0.490和0.599；第二次评估时则分别为0.759、0.772和0.858。由此可见，AO分型的一致性从中度提升至显著水平，AO/OTA分型则从中度提升至近乎完美水平。观察者间一致性整体处于显著水平（0.61~0.80），Neer、AO及AO/OTA分型的Kappa值分别为0.669、0.715和0.780。本研究为横断面观察性研究，证据等级为III级。