Interobserver Agreement Between On-Call Radiology Residents and Radiology Specialists in the Diagnosis of Pulmonary Embolism using Computed Tomography Pulmonary Angiography

Objective: The objective of this study was to assess the interobserver agreement between on-call radiology residents and radiology specialists in the evaluation of pulmonary embolism (PE) using computed tomographic pulmonary angiography (CTPA). Materials and Methods: Single center, prospective cohort study of 119 consecutive inpatients and outpatients with clinically suspected PE in whom CTPA was performed during out-of-office hours and weekends. The on-call radiology resident interpreted the CTPA for the presence of PE. An experienced radiology specialist, without knowledge of earlier reading, reviewed the CTPA the following morning. In discordant cases, a consensus reading was conducted. The radiology specialists' assessment and the consensus reading in case of discordance were considered as the gold standard. Results: Five CTPA studies were excluded from the analysis. In the remaining cases, radiology residents and radiology specialists agreed on the interpretations of CTPAs (no PE vs PE present) in 106 (93%) of the 114 cases, with a K value of 0.84 (95% confidence interval, 0.74-0.95). The consensus reading equally disagreed with both radiology resident and radiology specialist in 8 (7%) of the 114 discordant cases. Seven out of 8 discordant cases had suboptimal scan quality. Conclusions: The assessment of CTPA in patients with suspected PE by radiology residents seems reliable during out-of-office hours.