Seeking medical treatment—from a routine check-up to life-saving care for a serious medical condition—requires you to place significant trust in medical professionals. And unfortunately, sometimes the advice or diagnoses we receive from medical professionals aren’t accurate, resulting in injury or loss. 

So, what happens when misdiagnosis occurs? Can the patient bring a medical malpractice claim against the medical professional who misdiagnosed them? 

Below, we’ll cover misdiagnosis and medical malpractice—including what misdiagnosis is, the different types of misdiagnosis that can occur, and the elements required for a misdiagnosed patient to bring a medical malpractice claim against a medical professional. 

What is Misdiagnosis? 

Misdiagnosis, in its simplest form, is an incorrect diagnosis (or lack of diagnosis) of a medical condition. 

For example, misdiagnosis occurs when a medical professional diagnoses a patient with a condition they don’t have or a condition different from what they have. Alternatively, failing to diagnose a patient with a condition they have could also constitute misdiagnosis. 

While a misdiagnosis itself does not necessarily cause direct harm or loss to a patient (though, given the trust patients place in their medical treaters, it can certainly result in loss of trust, stress, and other challenging emotions), the events that occur following a misdiagnosis can be catastrophic for patients. 

Some of the potential impacts of misdiagnosis include: 

  • Worsening of a patient’s condition; 
  • A delay in receiving the correct diagnosis (and corresponding treatment); and
  • Negative health impacts from receiving inappropriate treatment (e.g., being prescribed medication for a condition you don’t have that negatively impacts your health). 

Can I Bring a Medical Malpractice Claim for Misdiagnosis? 

As each medical malpractice case is unique, speaking with a medical malpractice lawyer is essential if you believe a medical professional misdiagnoses you. They will be in the best position to assess the facts of your case and determine whether your situation is appropriate for advancing a medical malpractice claim. 

However, we have provided a summary below to provide further context on how the law treats misdiagnosis. 

Misdiagnosis and Negligence 

Misdiagnosis—and medical malpractice, generally—is assessed under the law of negligence. Under the principles of negligence, a patient claiming that a medical professional committed medical malpractice must prove the following: 

  • The medical professional who misdiagnosed the patient owed the patient a duty of care; 
  • The medical professional breached their standard of care by misdiagnosing the patient; 
  • The medical professional’s misdiagnosis and failure to meet their standard of care caused or contributed to the injury or loss claimed by the patient; and
  • The patient suffered actual injury or loss as a result of the misdiagnosis. 

We’ll explore each of these requirements in further detail below. 

The Duty of Care for Medical Professionals and Misdiagnosis 

In medical malpractice, medical professionals are generally considered to owe a duty of care to their patients.

However, when it comes to misdiagnosis claims, it can be challenging to identify which medical professionals owe the patient a duty of care, especially in cases where multiple medical professionals are involved (say, where a treating physician refers their patient for testing or specialists, and one or more of the medical professionals’ actions or inactions contribute to a misdiagnosis). To that end, misdiagnosis claims often require consideration of different actors’ respective duties to a patient. 

The Standard of Care for Medical Professionals and Misdiagnosis

Determining the standard of care required of medical professionals can become especially difficult when dealing with a misdiagnosis claim. After all, medical professionals are human and make mistakes. 

Ultimately, the question when determining whether a medical professional breached the standard of care owed to a patient due to a misdiagnosis is: did the medical professional’s action (or inaction) meet the standard expected of a reasonable, prudent, and diligent medical professional in the same circumstances? 

This analysis requires a thorough analysis of the circumstances and evidence available, keeping in mind that a medical professional could breach their standard of care in several different ways in relation to a patient’s care. 

Causation and Misdiagnosis 

Even if a medical professional breached their standard of care to a patient, it doesn’t necessarily mean that their breach caused the patient’s injury. 

For example, if a patient sues a medical professional and alleges that they failed to provide the patient with a particular treatment, but it is determined that the treatment in question would not have reduced the injury or loss claimed by the patient, the medical professional’s failure to provide the treatment would not be considered a cause or contributing factor for the plaintiff’s injury. 

In short, a “causal connection” must exist between the medical professional’s action (or inaction) and the patient’s alleged injuries. It may not be enough to claim that a medical professional failed to do something (like direct the patient to a particular treatment protocol) if that treatment protocol would not have made a difference to the patient’s condition. 

Injury or Loss and Misdiagnosis  

Finally, to establish entitlement to damages in a medical malpractice case, the patient must establish that they actually sustained injury or loss due to misdiagnosis. For example, if a doctor misdiagnoses a condition and the patient doesn’t suffer loss or harm as a result of that misdiagnosis (or if the misdiagnosis is caught quickly and corrected by the medical professional), the patient will almost certainly not be successful in establishing an entitlement to damages. 

Conclusions on Misdiagnosis and Medical Malpractice

While the above information should give you a good sense of the tests needed to establish a solid medical malpractice claim, every case is different. Medical malpractice claims are rarely clear-cut and require extensive knowledge of the law, investigation, and, often, the assistance of expert evidence. Regardless of your situation following a misdiagnosis, speaking with an experienced medical malpractice lawyer is a prudent step to learn more about your rights and determine whether you should start a claim. 

Experienced Medical Malpractice Lawyers Serving Ottawa, Cornwall, Kingston, and North Bay

Tierney Stauffer LLP’s experienced team of medical misdiagnosis lawyers have decades of experience working with victims of medical negligence. After meeting with you to discuss the details of your case, we will provide you with the advice and guidance you need to move forward. Contact us at 1-888-799-8057 or online for a consultation with one of our experienced medical malpractice lawyers.


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