Evaluation of Coronary CTA Appropriateness Criteria^® in an Academic Medical Center

Background: The aim of this study was to evaluate published appropriateness criteria for CT angiography (CTA) at the authors' academic medical center. Methods: Two observers independently reviewed the medical records of 251 patients who had undergone dual-source coronary CTA from June 1 to December 31, 2007. Patients were assigned to indications from 1 of 7 tables from the American College of Cardiology Foundation and ACR Appropriateness Criteria^®. Agreement between the two observers was assessed using κ statistics. Disagreements were resolved by consensus panel. The final numbers of appropriate, uncertain, inappropriate, and not classifiable indications were recorded. Results: Indications for testing were classified as appropriate in 69 patients (27%), inappropriate in 42 patients (17%), and uncertain in 25 patients (10%). One hundred fifteen indications for coronary CTA (46%) were not classifiable. Analysis of interobserver variability for overall appropriateness yielded a κ value of 0.31, which was considered to indicate fair agreement. Conclusion: The results of this study suggest that a significant proportion (46%) of the coronary CTA studies performed at the authors' institution are for indications that are not covered by the published appropriateness criteria. Modifications to these criteria could help decrease the number of studies that are not classifiable. Physician education could decrease the number of inappropriate studies.