Cost-effectiveness analysis of the Ottawa Ankle Rules.

STUDY OBJECTIVE To conduct an incremental cost-effectiveness analysis of implementation of the Ottawa Ankle Rules in emergency departments in the United States and Canada. DESIGN A decision analytic approach to technology assessment. Clinical decision rules that allow physicians to be more selective in their use of radiography were compared with current practice in a decision analytic model. SETTING A university hospital adult ED. PARTICIPANTS ED physicians instructed in the use of the Ottawa Ankle Rules for adult patients with ankle injury. RESULTS Radiography, waiting time, lost productivity, and medicolegal costs were calculated. In the United States, the savings varied between US$614,226 and US$3,145,910 per 100,000 patients, depending on the charge rate for radiography. In Ontario, Canada, the total savings were CAN$730,145 per 100,000 patients. One- and two-way sensitivity analyses that varied the rate of missed fractures, cost of radiography, probability of lawsuits, and cost of lawsuits did not change the results substantially. CONCLUSION Implementation of the Ottawa Ankle Rules would result in significant savings of health care dollars despite the cost of missed fractures including litigation costs.