Stiell I G, Greenberg G H, McKnight R D, Nair R C, McDowell I, Reardon M, Stewart J P, Maloney J
Division of Emergency Medicine, University of Ottawa, Ontario, Faculty of Medicine, Canada.
JAMA. 1993 Mar 3;269(9):1127-32. doi: 10.1001/jama.269.9.1127.
To validate and refine previously derived clinical decision rules that aid the efficient use of radiography in acute ankle injuries.
Survey prospectively administered in two stages: validation and refinement of the original rules (first stage) and validation of the refined rules (second stage).
Emergency departments of two university hospitals.
Convenience sample of adults with acute ankle injuries: 1032 of 1130 eligible patients in the first stage and 453 of 530 eligible patients in the second stage.
Attending emergency physicians assessed each patient for standardized clinical variables and classified the need for radiography according to the original (first stage) and the refined (second stage) decision rules. The decision rules were assessed for their ability to correctly identify the criterion standard of fractures on ankle and foot radiographic series. The original decision rules were refined by univariate and recursive partitioning analyses.
In the first stage, the original decision rules were found to have sensitivities of 1.0 (95% confidence interval [CI], 0.97 to 1.0) for detecting 121 maleolar zone fractures, and 0.98 (95% CI, 0.88 to 1.0) for detecting 49 midfoot zone fractures. For interpretation of the rules in 116 patients, kappa values were 0.56 for the ankle series rule and 0.69 for the foot series rule. Recursive partitioning of 20 predictor variables yielded refined decision rules for ankle and foot radiographic series. In the second stage, the refined rules proved to have sensitivities of 1.0 (95% CI, 0.93 to 1.0) for 50 malleolar zone fractures, and 1.0 (95% CI, 0.83 to 1.0) for 19 midfoot zone fractures. The potential reduction in radiography is estimated to be 34% for the ankle series and 30% for the foot series. The probability of fracture, if the corresponding decision rule were "negative," is estimated to be 0% (95% CI, 0% to 0.8%) in the ankle series, and 0% (95% CI, 0% to 0.4%) in the foot series.
Refinement and validation have shown the Ottawa ankle rules to be 100% sensitive for fractures, to be reliable, and to have the potential to allow physicians to safely reduce the number of radiographs ordered in patients with ankle injuries by one third. Field trials will assess the feasibility of implementing these rules into clinical practice.
验证并完善先前得出的临床决策规则，以助于在急性踝关节损伤中高效使用X线摄影。
前瞻性调查分两个阶段进行：验证并完善原始规则（第一阶段）以及验证完善后的规则（第二阶段）。
两家大学医院的急诊科。
急性踝关节损伤成人的便利样本：第一阶段1130名符合条件的患者中有1032名，第二阶段530名符合条件的患者中有453名。
急诊医生对每位患者评估标准化临床变量，并根据原始（第一阶段）和完善后（第二阶段）的决策规则对X线摄影需求进行分类。评估决策规则正确识别踝关节和足部X线摄影系列骨折标准的能力。通过单变量和递归划分分析完善原始决策规则。
在第一阶段，发现原始决策规则检测121例踝关节骨折的敏感度为1.0（95%置信区间[CI]，0.97至1.0），检测49例中足骨折的敏感度为0.98（95%CI，0.88至1.0）。对于116例患者规则的解读，踝关节系列规则的kappa值为0.56，足部系列规则的kappa值为0.69。对20个预测变量进行递归划分得出了踝关节和足部X线摄影系列的完善决策规则。在第二阶段，完善后的规则显示检测50例踝关节骨折的敏感度为1.0（95%CI，0.93至1.0），检测19例中足骨折的敏感度为1.0（95%CI，0.83至1.0）。估计踝关节系列X线摄影潜在减少34%，足部系列减少30%。如果相应决策规则为“阴性”，踝关节系列骨折的概率估计为0%（95%CI，0%至0.8%），足部系列为0%（95%CI，0%至0.4%）。
完善和验证表明渥太华踝关节规则对骨折的敏感度为100%，可靠，并且有可能让医生安全地将踝关节损伤患者的X线摄影检查数量减少三分之一。现场试验将评估将这些规则应用于临床实践的可行性。
