Unnecessary diagnostic imaging requested by medical students during a first day of residency simulation: an...

Physicians' choice of appropriate tests in the diagnostic process is crucial for patient safety. The increased use of medical imaging has raised concerns about its potential overuse. How appropriately medical students order diagnostic tests is unknown. We explored their ordering behavior of diagnostic imaging during a simulated first day of residency.

In total, 492 undergraduate medical students participated in the simulation. After history taking with simulated patients, the students used an electronic system for requesting diagnostic tests. The analysis focused on 16 patient cases, each managed by at least 50 students. We calculated the total number of ordered images and unnecessary radiation exposure in millisievert per patient and performed one sample t-tests (one tailed) with an expected mean of zero on a Bonferroni-corrected alpha level of 0.003 for the independent variable of unnecessary radiation exposure.

Unnecessary diagnostic imaging was ordered across all patient cases. Ultrasound, especially abdominal ultrasound, X-rays of the thorax, and abdominal CTs were notably overused in 90.9%, 80.0%, and 69.2% of all patient cases, respectively. Unnecessary requests of imaging related to radiation resulted in radiation over-exposure for nearly all patients, with 37.5% of all patients being exposed to a significant radiation overdose on average.

Medical students' overuse of diagnostic imaging can be explained by patient-related factors like anxiety and medical factors like missing clinical information leading to cognitive biases in patient workup. This suggests the need for interventions to improve students' clinical decision-making and reduce cognitive biases. Investigating student-specific factors being associated with overuse of diagnostic imaging would be of additional interest.