Avoiding Legal Trouble

Three Examples Of Cognitive Biases That May Lead To Diagnostic Errors

Diagnostic errors are some of the leading causes of medical malpractice. Some of the top causes of diagnostic errors can be classified under cognitive traps. A cognitive trap is an erroneous conclusion an individual makes when they analyze a situation in an illogical manner. Cognitive traps have multiple causes, such as these three:


Filtering occurs when the doctor over focuses on one serious symptom at the expense of other less serious ones. When a doctor filters out the symptoms, it is as if the one they are focusing on and magnifying is the only (relevant) one. This can easily make the doctor exclude other possible diagnoses.

For example, symptoms of appendicitis and urinary tract infections (UTIs) sometimes overlap. This is why there are tests designed to lead doctors to correct diagnoses. However, when a doctor focuses on one symptom at the expense of others, they may diagnose a UTI when the patient has appendicitis or vice versa.

Confirmation Bias

Confirmation bias occurs when the doctor already has a preconception before coming up with a diagnosis. When such a physician examines a patient, they are only looking for information (read symptoms) to support their preconception. In the end, other possible diseases that the patient may be suffering from aren't considered.

For example, the medical community knows that smoking, lack of regular exercise, and being overweight are some of the risk factors for a heart attack.  Therefore, when a patient whose history checks all those boxes comes in complaining of chest pains, it's easy to assume that the patient has a heart attack. The doctor may then look for signs of a heart attack, which may be there even though the patient is actually suffering from ailments with similar symptoms, such as pneumonia or a panic attack.

The Ambiguity Effect

The ambiguity effect is likely to lead to wrong diagnoses in patients suffering from rare diseases. The ambiguity effect occurs when the physician is dealing with symptoms common to two diseases, one of which the doctor is experienced in and another in which the doctor has limited knowledge and experience. In such a case, the doctor is likely to go with the condition that they are fully conversant with.

For example, a patient complaining of coughs and chest pains may be diagnosed with a respiratory infection even if the doctor has heard that thymoma can also cause the same symptoms. This is possible if the doctor has more experience with respiratory infections than thymoma, which is a rare type of cancer.

Do you feel that your medical condition was misdiagnosed? Talk to a medical malpractice attorney, like one from Littman & Babiarz Law Office, whether or not you suspect the wrong diagnosis was caused by the doctor's cognitive bias. The attorney will analyze your case and help you decide whether you have a valid claim.