AbstractPurpose:This study is an evaluation of the ability of medically trained and controlled emergency medical dispatchers to use telephone triage techniques to direct the appropriate prehospital unit to an emergency scene.Methods:Emergency dispatchers, educated in a formal emergency medical dispatch program, were assigned one of four triage priorities to incoming 9-1-1 calls. The actual field management delivered for each patient was compared with the dispatcher's triage to determine the appropriateness of triage.Results:A total of 1,045 consecutive calls were reviewed with 74.4% sorted as needing advanced life support (ALS) units on scene; 65.3% (95% CI, 61.9 to 68.6%) of these calls required ALS intervention. A total of 3.4% of the runs sorted to the non-ALS response groups were identified to have required ALS intervention. Comparing the need for ALS intervention, a significant difference was found between the triage groups.Conclusion:Emergency medical dispatchers, using a formal system for telephone triage, are able to direct appropriate prehospital resources to the emergency scene.