Evaluation of clinical decision rules

The final goal of decision making rules is to help the clinician make a med ical decision and limit heterogeneous practices. Three steps are needed to develop decision making rules for use in daily practice: 1) construction, 2 ) prospective validation, 3) study of its impact in terms of clinical pract ice and economics. The aim of this work was to review, the details of these different steps basing the research on the Ottawa rules aimed at defining indications for radiography in patients presenting at the emergency room fo r ankle trauma.