Fig. 16

Availability and regret bias causing faulty reasoning error. A 41-year-old male patient with aortic valve stenosis was admitted to the Emergency Department with epigastric pain during the COVID-19 pandemic. A thoracoabdominal CT was ordered to assess the aortic stenosis, lung parenchyma and possible causes of epigastric pain. The on-call radiologist on the night-shift correctly described the CT findings as cardiomegaly, bilateral ground-glass opacities predominantly in the upper lobes of the lungs (blue arrows, b), thickening of the interlobular septae (red arrows, a, d) and bilateral pleural effusion. Before the CT of this patient, the radiologist had reported a large number of CTs compatible with viral pneumonia during the night-shift. In addition, he had overlooked a patient with positive chest CT finding for COVID-19 pneumonia on a previous night-shift, so he was overly sensitive about the diagnosis of COVID-19. Having been “burned once,” he did not want to underdiagnose the possibility of COVID-19. Therefore, these CT findings were attributed to pulmonary infection by indicating that COVID-19 pneumonia could not be excluded in the differential diagnosis. However, he did not mention the possibility of pulmonary edema. Viral pneumonia treatment was started due to the radiologist's opinion, and a reverse transcriptase polymerase chain reaction (RT-PCR) test for COVID-19 was ordered and reported as negative. On the following day, the attending emergency radiologist informed emergency physicians that the CT findings were primarily suggestive of cardiogenic pulmonary edema. The patient then showed a dramatic response to cardiogenic pulmonary edema treatment. As the frequency of viral pneumonia was greatly increased during the pandemic, and the radiologist had a lot of experience about this condition, availability bias resulted in misjudgment and faulty reasoning error. Although regret bias due to previous negative experience eliminated the possibility of overlooking another case of COVID-19 pneumonia for the radiologist, it also contributed to the error by affecting the thought process