Observer variation in the radiographic classification of fractures of the neck of the femur using Garden's system.

By means of Kappa statistics, we calculated the inter- and intra-observer variation in the classification of fractures of the neck of the femur according to Garden's system. Radiographs of 96 consecutive patients were assessed independently by six observers who agreed on classification for only 14 fractures (15%). The level of agreement was poor for the overall classification (Kappa = 0.39). When reducing Garden's system into non-displaced (Stage I and II) and displaced fractures (Stage III and IV) the level of agreement became acceptable (Kappa = 0.68). However, problems remain in distinguishing Stage II and Stage III fractures, and further improvements in the classification system are necessary.