Ordering CT pulmonary angiography to exclude pulmonary embolism: defense versus evidence in the emergency room.

Purpose: To identify reasons for ordering computed tomography pulmonary angiography (CTPA), to identify the frequency of reasons for CTPA reflecting defensive behavior and evidence-based behavior, and to identify the impact of defensive medicine and of training about diagnosing pulmonary embolism (PE) on positive results of CTPA.

Methods: Physicians in the emergency department of a tertiary care hospital completed a questionnaire before CTPA after being trained about diagnosing PE and completing questionnaires.

Results: Nine hundred patients received a CTPA during 3 years.