FAILED VALIDATION OF A CLINICAL DECISION RULE FOR THE USE OF RADIOGRAPHY IN ACUTE ANKLE INJURY

Aim. To validate the Ottawa clinical decision rule for the use of radi ography in acute ankle injuries. Method. A prospective, multicentre tr ial of 350 adult patients presenting with acute ankle injuries consist ing of correlation of the features of the Ottawa clinical decision rul e with the results of x-rays. Results. There were 75 fractures in 350 patients, five of which would have been missed by the clinical decisio n rule. The sensitivity of the rule was 93% with a specificity of 11%. The positive predictive value was 22%, the false negative rate 14%. F ractures that would have been missed by the clinical decision rule inc luded one unstable fracture of the ankle, one fracture of the talus, o ne calcaneal fracture and one fracture each of the cuboid and navicula r. Conclusion. The Ottawa clinical decision rule for the use of radiog raphy in acute ankle injuries is unacceptable for application in emerg ency departments in New Zealand due to a high false negative rate.