We sought to determine if CT utilization rates varied by characteristics of the physician. A chart review was performed at an urban academic emergency department (ED) to identify all the CT scans ordered and patients seen for subjects 21 years of age and older by physicians between January 2001 and December 2008. "Years of experience" was defined as years of practice after residency. Various experience cutoffs were determined a priori. Physicians were labeled "academic" if they had reduced clinical hours for academic duties and "clinical" if they were physicians without "protected time." We categorized physicians as "high users" (top quartiles) and "low users" (bottom quartiles), and compared utilization rates from 2001 to 2003 to utilization rates from 2005 to 2007. There were 280 physician-years of practice, with an average experience of 6.1 years. When comparing groups of physicians with more or less than 3, 5, 10, and 15 years of experience, there were no statistically significant differences between the number of CT scans per 1,000 visits (p = 0.85; p = 0.21; p = 0.57; p = 0.08, respectively). Comparison between clinical and academic physicians yielded no differences (clinical = 98.4, academic = 104.2, p = 0.10). Low users ordered 78 CT scans per 1,000 patient visits (95 % CI 76.6-78.5), as compared to the high users that ordered 135 CT scans per 1,000 patient visits (95 % CI 131.8-139.0). We found that all of physicians stayed within their quartiles except one. While there was substantial variation among CT utilization rates by physicians at this urban emergency department, our data shows no differences between physicians with more or less clinical experience and no change in individual utilization patterns during the study period.