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Quality Care Begins with an Accurate Diagnosis

VisualDx can help physicians avoid diagnostic pitfalls by guiding a process of expert reasoning to assist in the building of strong differentials, and by providing visuals for direct comparison with patient presentations. The use of diagnostic decision support to increase cognitive awareness helps physicians recognize knowledge limitations and cognitive biases, such as confirmation bias and premature closure of a diagnosis, to reduce misdiagnosis and optimize patient care.

Cognitive Reasoning and Diagnostic Error

Research has examined how doctors think to investigate cognitive biases that could potentially lead to error and patient harm.1 In one study of 100 cases of diagnostic error (90 injuries including 33 deaths), 74% were attributed to errors in cognitive reasoning, with the most common cause of misdiagnosis being the failure to consider reasonable alternatives after early possible diagnosis.2 Other common causes include physician overconfidence,3 faulty context generation, misjudging findings, faulty perception, and errors connected with the use of shortcuts (heuristics).4


Prevent Cognitive Errors with VisualDx – Case Studies


Case 1:

The patient was a 66-year-old female being treated for multiple medical problems including new-onset seizures (medication: Dilantin [phenytoin]) and lobar pneumonia (medication: IV cephalosporin). She developed a widespread exanthematous rash while in the ICU. There was an elevated WBC with eosinophilia, and LFTs were elevated. IV antibiotic therapy was felt to be the cause of the rash and discontinued. The rash persisted, and liver enzymes continued to rise. The persistence of the rash at 7 days after discontinuing the antibiotic was felt to be secondary to the antibiotic, as the rash appeared like a common antibiotic-induced “drug rash.”

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Case 2:

The patient was a 42-year-old HIV-positive male with a history of non-compliance with medications. He was admitted for pneumonia. The attending physician was told by the emergency room nurse that the patient had a past history of psoriasis. The patient was noted to have a rash on admission. The attending physician concluded that the rash was consistent with psoriasis, even though it was in a new location for the patient.

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Case 3:

The patient was a 52-year-old smoker evaluated for a dental abscess at a primary care walk-in clinic. The clinician noted a white plaque on the contralateral tongue. The diagnosis of oral candidiasis was made, and the patient was discharged with a prescription for oral nystatin.

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Case 4:

The patient was a 55-year-old female with two prior hospital admissions for cellulitis. She presented to the emergency department with itchy redness of the lower leg and was admitted for IV antibiotic therapy for cellulitis.

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Case 5:

A 23-year-old male presented to the emergency room with eye pain. He regularly wore contact lenses. On slit lamp examination in the emergency room, a corneal defect was observed. The diagnosis of traumatic erosion of the cornea was made. The emergency physician prescribed an antibiotic ophthalmic ointment and instructed the patient to follow up with ophthalmology. The patient was seen by an ophthalmologist 1 week later.

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  1. Groopman J. How Doctors Think. New York, NY: Houghton Mifflin; 2007.
  2. Graber ML, Franklin N, Gordon R. Diagnostic error in internal medicine. Arch Intern Med. 2005;165(13):1493-1499. [PubMed].
  3. Berner ES, Graber ML. Overconfidence as a cause of diagnostic error in medicine. Am J Med. 2008;121(5 Suppl):S2-S23. [PubMed].
  4. Croskerry P. The importance of cognitive errors in diagnosis and strategies to minimize them. Acad Med. 2003;78(8):775-780. [PubMed].