Variation in the utilization and positivity rates of CT pulmonary angiography among emergency physicians at a tertiary academic emergency department.

We examined the patient and physician characteristics related to the use and yield of computed tomography pulmonary angiogram (CTPA) for the diagnosis of pulmonary embolism (PE) at a tertiary academic hospital emergency department (ED). A cross-sectional retrospective study was conducted on 835 consecutive ED patients with suspected PE who underwent CTPA. Radiology report data were extracted from our institution's RIS PACS software (Syngo Imaging, Siemens) based on a targeted search of all CTPA reports from 2010 to 2012. Utilization and PE positivity rates of CTPA were calculated and correlated with patient characteristics including age and gender, as well as emergency physician (EP) characteristics including gender, years in practice, and training certification. Acute PE was diagnosed in 17.8 % of patients. A further 32.9 % of the scans were negative for PE but had other clinically significant findings. We found higher utilization rates in female and older patients (p < 0.001), however, without corresponding differences in PE positivity rates compared to their male and younger counterparts. There was a high inter-physician variation in CTPA utilization rate (range 0.21-0.77 scans per 100 patients seen) and PE positivity rate (range 6.7-38.9 %). However, neither rates correlated with EP years of experience (p > 0.15 with cut-offs at 5, 10, and 20 years post-residency), gender (p = 0.59), or training certification (p = 0.56 between EPs certified by the 5-year program of the Royal College of Physicians of Canada versus the 3-year program of the College of Family Physicians of Canada). Our study demonstrated considerable inter-physician variability in the utilization and PE positivity rates of CTPA. These results suggest an opportunity for a more standardized approach to the use of CTPA among EPs at our institution.