Study objectives: We determine whether the use of abdominal computed tomography (CT) alters diagnosis and disposition in elderly patients presenting to the emergency department (ED) with abdominal pain. Methods: This prospective, observational, multicenter study consisted of a convenience sample of patients aged 60 years and older presenting to 1 of 4 participating EDs with abdominal pain. Patients with abdominal trauma or surgery within the previous 4 weeks were excluded. We analyzed the overall rate of CT use and compared the concordance of ED diagnosis (diagnosis) to final diagnosis (discharge or 2-week follow-up). ED diagnosis was considered concordant to final diagnosis if the ED diagnosis was included among the final diagnoses. In a subgroup of patients (N=100), we used a real-time questionnaire to determine percentage of change (95% confidence interval [CI]) in diagnosis and disposition after CT scan results. Results: Four hundred thirty-eight (87%) of 501 consenting patients were enrolled. Of these, 179 (41%) patients had a CT scan as part of their evaluation. Concordance of ED diagnosis to final diagnosis in admitted patients was 74.1% (95% CI 65.0% to 81.6%) in those receiving CT versus 74.5% (95% CI 66.1% to 81.3%) in those without CT. In the subgroup of patients with real-time questionnaire information, 54 (54%) had CT performed. The percentage of change in diagnosis or disposition after CT in this group was 17 of 54 (32%, 95% CI 19.9% to 45.7%) and 19 of 54 (35%, 95% CI 23.0% to 49.4%), respectively. Conclusion: CT is used for more than 40% of elderly patients treated in the ED for abdominal pain. No difference was observed in concordance of ED to final diagnosis between patients with or without CT. Diagnosis and disposition were each altered about one third of the time in patients for whom CT was obtained. Study objectives: We determine whether the use of abdominal computed tomography (CT) alters diagnosis and disposition in elderly patients presenting to the emergency department (ED) with abdominal pain. Methods: This prospective, observational, multicenter study consisted of a convenience sample of patients aged 60 years and older presenting to 1 of 4 participating EDs with abdominal pain. Patients with abdominal trauma or surgery within the previous 4 weeks were excluded. We analyzed the overall rate of CT use and compared the concordance of ED diagnosis (diagnosis) to final diagnosis (discharge or 2-week follow-up). ED diagnosis was considered concordant to final diagnosis if the ED diagnosis was included among the final diagnoses. In a subgroup of patients (N=100), we used a real-time questionnaire to determine percentage of change (95% confidence interval [CI]) in diagnosis and disposition after CT scan results. Results: Four hundred thirty-eight (87%) of 501 consenting patients were enrolled. Of these, 179 (41%) patients had a CT scan as part of their evaluation. Concordance of ED diagnosis to final diagnosis in admitted patients was 74.1% (95% CI 65.0% to 81.6%) in those receiving CT versus 74.5% (95% CI 66.1% to 81.3%) in those without CT. In the subgroup of patients with real-time questionnaire information, 54 (54%) had CT performed. The percentage of change in diagnosis or disposition after CT in this group was 17 of 54 (32%, 95% CI 19.9% to 45.7%) and 19 of 54 (35%, 95% CI 23.0% to 49.4%), respectively. Conclusion: CT is used for more than 40% of elderly patients treated in the ED for abdominal pain. No difference was observed in concordance of ED to final diagnosis between patients with or without CT. Diagnosis and disposition were each altered about one third of the time in patients for whom CT was obtained.