Five-point triage assessment scales currently used in many emergency departments (EDs) across the country have been shown to be accurate and reliable. We have found the system to be highly predictive of outcome (hospital admission, intensive care unit/operating room admission, or death) at either extreme of the scale but much less predictive in the middle triage group. This is problematic because the middle triage acuity group is the largest, in our experience comprising almost half of all patients. Patients triaged to the 2 highest acuity categories (A and B) have admission/ED death rates of 76% and 43%, respectively. In contrast, the 2 lowest acuity categories (D and E) have admission/ED death rates of 1% or less. The middle category (C), however, has an overall admission/ED death rate of 10%, too high to be comfortable with prolonged delays in the ED evaluation of these patients. We studied this group to determine if easily obtainable clinical factors could identify higher-risk patients in this heterogeneous category. Data were obtained from a retrospective, cross-sectional study of all patients seen in 2001 at an urban academic hospital ED. The main outcome measure for multivariate logistic regression models was hospital admission among patients triaged as acuity C. Acuity C patients who were 65 years or older, presenting with weakness or dizziness, shortness of breath, abdominal pain, or a final diagnosis related group diagnosis of psychosis, were more likely to be admitted than patients originally triaged in category B. These findings suggest that a few easily obtainable clinical factors may significantly improve the accuracy of triage and resource allocation among patients assigned with a middle-acuity score.