Frequency of Use of Imaging Tests in the Diagnosis of Pulmonary Embolism: Effects of Physician Specialty, Patient Characteristics, and Region

The purpose of this study was to ascertain whether clinical practice in diagnosing pulmonary embolism is consistent with recommendations in the literature and to explore variations in practice across site of care (e.g., emergency department), physician and patient characteristics, and geographic location. Medicare 5% research identifiable files were analyzed. The cases of patients with emergency department visits or inpatient stays for a diagnosis of pulmonary embolism or for symptoms related to pulmonary embolism (shortness of breath, chest pain, and syncope) were identified. We determined the number of patients who underwent each type of relevant imaging test and evaluated variations in the first non-chest-radiographic test by site of care and treating physician specialty. Using logistic regression, we studied variations in the use of common imaging tests, exploring variations associated with patient characteristics, physician specialty, site of care, and geographic location. For patients in whom pulmonary embolism might have been suspected, the most common tests were echocardiography (26% of the patients), CT or CT angiography of the chest (11%), cardiac perfusion study (6.9%), and duplex ultrasound (7.3%). For patients with an inpatient diagnosis of pulmonary embolism, the most common tests were chest CT or CT angiography (49%), duplex ultrasound (18%), echocardiography (10.9%), and ventilation-perfusion scintigraphy (10.9%). For patients for whom pulmonary embolism might have been suspected, many large variations were found in practice patterns among physician specialties and geographic locations. There were fewer variations among patients with the inpatient diagnosis of pulmonary embolism. Physician practice in the diagnosis of pulmonary embolism is broadly consistent with recommendations. However, variations by physician specialty and geographic location may be evidence of inappropriate imaging.