Doctor’s Misdiagnosis


There have been many lawsuits that stem from the misdiagnosis or delayed diagnosis of a patient’s medical condition, injury, or illness.  When a doctor makes an error that results in the incorrect treatment, a delay in treatment, or a complete lack of treatment, then the patient’s condition may worsen, or the patient may even die.  However, even if the doctor makes a mistake while diagnosing the patient, that is not necessarily enough to have a successful medical malpractice lawsuit.

Doctors are not legally responsible for every diagnostic error.  Generally, in order prevail in a medical malpractice lawsuit for incorrect diagnosis; the patient must prove three things:

  1. That a doctor-patient relationship existed.
  2. The doctor was negligent (such as failed to provide treatment in a reasonably skillful and competent manner).
  3. The actual injury was caused by the doctor’s negligence.

Misdiagnosis or delayed diagnosis in itself is not necessarily evidence of negligence.  Diagnostic errors can be made by skillful doctors who use reasonable care.  The determination of whether the doctor acted competently is the key.  This involves evaluations of what the doctor did and did not do as they arrived at the diagnosis.  Determining this means looking at the “differential diagnosis” method used by the doctor as they make their treatment determinations.

A differential diagnosis is the systematic method used by doctors to identify a patient’s disease or condition.  The doctor uses their preliminary evaluation to make a list of diagnosis, ranked by order of probability.  The strength of each diagnosis is tested by making further medical observations of the patient.  Doctors will ask the patient detailed questions about their symptoms and medical history, order tests, or refer the patient to specialists.  As the investigation progresses, the doctor should be able to rule out several potential diagnoses, leaving only one diagnosis in the end.  However, this is not always the case.  Sometimes information will cause the doctor to add to the list.

To prove a case based on diagnostic error, the patient needs to show that a doctor in a similar specialty, under similar circumstances, would not have misdiagnosed the illness or condition.  The patient will need to prove two things:

  1. The correct diagnosis was not included on the differential diagnosis list, and a doctor of reasonable skill and competence would have under similar circumstances.
  2. The correct diagnosis was included on the differential diagnosis list, but the doctor did not perform the appropriate tests or seek the opinion of a specialist to investigate the diagnosis’ viability.

The misdiagnosis or delayed diagnosis must also have caused the patient to be injured or for the condition to have progressed beyond where it would have had the correct diagnosis been made in a timely manner, and that the progression of the condition had a negative impact on the patient’s treatment.

But what do you think?  I would love to hear from you!  Leave a comment or I also welcome your phone call on my toll-free cell at 1-866-889-6882 or you can drop me an e-mail at  You are always welcome to request my FREE book, The Seven Deadly Mistakes of Malpractice Victims, at the home page of my website at