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Errors and matters of judgment

Even good doctors make mistakes

Exercise of judgment

Close up of young male physician thinkingThe term error in judgment is used frequently in medical practice but this term is a misnomer. In fact, an error in judgment is not an error; it refers to the exercise of judgment in clinical decision making.

An error in judgment (or more accurately, a matter of judgment or the exercise of judgment) is a reasonable decision or choice made carefully at the time, but in retrospect might not be considered by some as the best choice or decision.

After an examination and thoughtful analysis of a patient's condition, a physician is not necessarily in breach of the duty toward a patient simply because the physician made a choice or a decision that was reasonable given the circumstances.

Diagnosing a condition or choosing among different therapeutic approaches are often exercises in clinical judgment.

Delays in diagnosis may occur because many conditions must progress to a clinical degree where the symptoms and signs suggest the diagnosis or at least indicate the need for further testing.

Reaching a final and confirmed diagnosis often requires assessing a patient several times, sometimes over a long period of time. Sometimes, however, system failures or problems in provider performance, or both, contribute to the delay.

Here are some representative Canadian court judgments:

"It is easy to be wise after the event and to condemn as negligence that which was only a misadventure."
    Lord Denning, 1954, a judgment cited in Canada

"(PGY4)... was not being faulted for her misdiagnosis of ... the patient's condition or for failing to recognize subtle changes in ECGs, this was a matter of judgment."

  • "median nerve block was a surprising choice but not a negligent one..."
  • "This choice was an error in judgment, not a negligent one."

"An error of judgment has long been distinguished from an act of unskilfulness or carelessness or due to lack of knowledge. Although universally accepted procedures must be observed, they furnish little or no assistance in resolving such a predicament as faced the surgeon. In such a situation a decision must be made without delay based on limited known and unknown factors; and the honest and intelligent exercise of judgment has long been recognized as satisfying the professional obligation." [REF]

Picard, E., Robertson, G. Legal liability of doctors and hospitals in Canada, 4th ed., 2007.

Case: A middle-aged man coming into ER with chest pain
Middle age man with chest pain in ER


A middle-aged male who smokes presents to the emergency department for evaluation of sudden onset of left-sided chest discomfort. His symptoms include dyspepsia, and numbness and tingling in the left arm and leg.

Blood pressure is normal in both arms, the cardiovascular and neurological examinations are normal, and repeated ECGs and serial cardiac markers remain negative.

After 8 hours of observation, the patient is discharged home to follow up with his family physician.

The patient continues to have intermittent chest pain, especially on inspiration.

Background continued

Three days later, when examined by his family physician, the patient is febrile and a chest X-ray infiltrate suggests left lower lobe pneumonia. He is started on antibiotics.

Three days later — 6 days after the initial hospital visit — the patient is seen by the family physician again and referred to an internist.

The internist documents a blood pressure that is the same and is within normal limits in each arm, no cardiac murmurs or rubs, and a normal neurological examination.

Another chest X-ray reveals a patchy consolidation in the left lung base. Laboratory work and an ECG remains normal, apart from a mildly elevated white blood count.

The internist also diagnoses pneumonia but changes the antibiotics to cover a wider spectrum of organisms.

Think about it

What do you think about the clinical care so far?


Two days later the patient collapses at home and cannot be resuscitated. A ruptured dissection of the descending thoracic aorta is found at autopsy.  

The many unusual features of the case, such as:

  • the pleuritic nature of the pain,
  • the signs and symptoms suggesting pneumonia,
  • the normal blood pressure in both arms, and
  • the absence of a cardiac murmur
would understandably make aortic dissection difficult to suspect prior to any further clinical deterioration.