The care team demonstrated anchoring, a diagnostic cognitive error that results from “locking” onto features of a patient's initial presentation and providing treatment for that diagnosis despite the appearance of new clinical information. In this patient, the care team anchored on the initial history and radiographic findings of constipation and failed to recognize or act upon additional clinical clues, including fever, leukocytosis, and worsening abdominal pain despite treatment, related to the correct diagnosis of cholecystitis.
Confirmation bias involves using or interpreting information (for example, diagnostic studies) in a way that confirms a current hypothesis. This cognitive error results from the tendency to look for evidence that confirms a suspected diagnosis rather than considering evidence that refutes that diagnosis and may lead to another diagnostic option. Because of anchoring to the initial diagnosis, the care team did not seek additional clinical evidence that could be interpreted to support that diagnosis.
Framing bias is a form of cognitive error that occurs when the way clinical information is presented, or “framed,” affects decisions based on that information. An example is the perception of increased effectiveness of a specific therapy when the benefit of treatment is reported in relative instead of absolute terms, since relative benefits frequently appear larger than absolute benefits. Similarly, clinical decisions based on cardiovascular risk may differ if the assessed risk is based on an annual event rate compared with a cumulative 10-year risk. Framing bias does not appear to be a significant factor in the outcome of this case.
Triage cueing occurs when the manner in which triage decisions are made influences the evaluation and diagnosis (for example, when a patient with chest pain is admitted to a cardiology service and receives an extensive evaluation for myocardial infarction rather than an evaluation for gastroesophageal reflux). This patient appears to have been appropriately triaged for initial management, but the subsequent changes in his clinical course were not addressed due to anchoring to the initial diagnosis.