Medical Malpractice: Misdiagnosis and Delayed Diagnosis

Some sources estimate that up to 40 percent of medical malpractice claims are based on either misdiagnosis or delayed diagnosis. Obviously, both of these errors can be harmless in certain circumstances and deadly in others. If you have been the victim of a diagnostic error, whether or not you have a valid medical malpractice claim depends on several factors.

The Doctor-Patient Relationship

To win a medical malpractice lawsuit based on a diagnostic error, you must prove that a doctor-patient relationship existed between you and the defendant. If there was no doctor-patient relationship at the time the alleged medical malpractice took place, you have no medical malpractice claim, although in certain circumstances you may still have an ordinary personal injury claim. Circumstances in which a doctor/patient relationship may be difficult or impossible to prove include:

  • You were injured in an auto accident witnessed by an off-duty doctor who proceeded to render first aid
  • You overheard the doctor offering medical advice at a party
  • The doctor acted as a consultant to your doctor and did not treat you directly

Generally speaking, to establish a doctor/patient relationship you must have asked the doctor to diagnose or treat you, and he must have agreed, although certain exceptions apply.


After establishing a doctor/patient relationship, you must also show that the doctor’s diagnosis (or lack thereof) was negligent in some way – in other words, your doctor must have failed to meet minimum professional standards. The mere fact that the doctor misdiagnosed your condition or failed to diagnose it at all is not enough to establish malpractice. You must show that the doctor breached his duty of care to you. Since a doctor is a highly trained professional, his duty of care to you is high – but that doesn’t mean he is expected to never make a mistake. The doctor’s precise duty of care may vary according to the circumstances – a specialist, for example, might be held to a higher duty of care than a general practitioner.


Even if the doctor was negligent, his negligence doesn’t matter if it wasn’t the cause of the illness or injury that you are complaining about. If your doctor failed to diagnose you with diabetes, for example, you will have no claim unless you can show that this failure harmed you in some way (you suffered kidney damage due to untreated diabetes, for example). A completely harmless error will not support a medical malpractice claim.

Causation is also relevant to the amount of damages you can recover. If your doctor misdiagnosed your stroke, for example, you cannot recover damages caused by the stroke itself (since it had already happened by the time the misdiagnosis occurred) – you can only recover an amount representing the extent to which the doctor’s misdiagnosis worsened your condition. If a patient dies because of a misdiagnosis, of course, a wrongful death lawsuit could be appropriate.

If you have suffered harm due to a doctor’s failure to properly diagnose you, you are likely to need a skilled medical malpractice lawyer to help you establish your claim.