Medical malpractice can lead to serious consequences, including injury, illness, disability and even death. One type of medical malpractice claim is medical misdiagnosis, which occurs when a patient is undiagnosed and therefore untreated, misinformed about their condition and given incorrect or improper treatment, or treated for a condition that they do not actually have. A victim may have grounds for damages against the doctor or health practitioner responsible.

The recent decision of the Court of Appeal for Ontario in Andrews v Pattison is an important reminder to seek early advice from a personal injury lawyer and file a medical malpractice claim in a timely manner in order to meet the limitation period. The Court rejected the plaintiff’s argument that the limitation period should start when the expert evidence was received.

What is the statutory limitation period?

According to section 4 of the Limitations Act 2002 and subject to exceptions, a proceeding must be commenced by the second anniversary of the day on which the “claim was discovered”.

Section 5(1) sets out a complex test for determining this day. 


5 (1) A claim is discovered on the earlier of,

(a) the day on which the person with the claim first knew,

(i) that the injury, loss or damage had occurred,

(ii) that the injury, loss or damage was caused by or contributed to by an act or omission,

(iii) that the act or omission was that of the person against whom the claim is made, and

(iv) that, having regard to the nature of the injury, loss or damage, a proceeding would be an appropriate means to seek to remedy it; 

However, if a reasonable person with the abilities and in the plaintiff’s circumstances ought to have known of these matters on an earlier day, that earlier day is the day that the claim is deemed to have been discovered.  Per section 5(2) of the Limitations Act, the plaintiff is presumed to have known of the four matters on the day the act or omission took place unless the contrary is proved.

Woman dies of lung cancer after complaining of shortness of breath

After complaining of shortness of breath and chest pain, the deceased received medical attention and treatment from the defendant’s doctor between 2008 and 2013. The defendant ordered a chest x-ray in late 2008 but discovered no anomalies. No further x-rays were ordered until May 2013, at which point an abnormality was identified, leading to a biopsy that confirmed a diagnosis of lung cancer.

The deceased sought legal counsel in February 2014 because she felt she might have lived longer if she had a chest x-ray earlier. She died in April 2014.

Plaintiffs commence negligence claim for misdiagnosis

The deceased’s family and estate trustees obtained expert opinions relating to the standard of care required by the doctor and whether the doctor’s treatment caused the deceased’s injury in the second half of 2015. They subsequently issued the claim in April 2016 – more than two years after the diagnosis of lung cancer and the deceased’s meeting with the lawyer, but slightly less than two years after her death.

The defendant applied to dismiss the action on the grounds that the plaintiffs discovered the claim more than two years before the date the claim was issued.

Motion judge determines claim was discovered at the time of the terminal cancer diagnosis

Justice McCarthy cited authorities that established that the commencement of the limitation period does not depend upon the plaintiff knowing with certainty that the defendant’s conduct was negligent or a lawyer advising a plaintiff that there is a valid cause of action. A plaintiff discovers a claim once in possession of sufficient facts upon which she could allege negligence.

His Honour recognized that in some medical malpractice cases, the plaintiff may require advice from a person who is medically trained. However, this would only be the case where the expert evidence contained new facts which had previously not been brought to light, which did not occur in this case.

Justice McCarthy held that the deceased and the plaintiffs had sufficient knowledge of the facts upon which to base a claim against the defendant as of May 2013 and certainly no later than February 2014. His Honour relied on the facts that the deceased was under the care of only the defendant for years prior to the diagnosis of advanced lung cancer, the plaintiffs were upset that a chest x-ray had not been previously ordered and questioned whether an earlier x-ray might have resulted in a different outcome, and they sought legal advice almost immediately.

Court of Appeal agrees and dismisses the plaintiffs’ claim

The plaintiffs appealed to the Court of Appeal, arguing that the limitation period did not begin to run until they received the expert reports in 2015. 

The Court of Appeal agreed with the motion judge’s findings, including the rejection of the plaintiffs’ argument that the potential negligence claim was not discoverable until the receipt of the expert reports. The Court explained that the determination of when a plaintiff has sufficient facts to discover the claim is not the same as the question of the discovery of the merits of the potential action. In other words, determining whether the person has a ‘good case’ can follow at a later stage.

As a result, the Court decided that the plaintiff’s claim was statute-barred because the court proceedings were commenced more than two years after the claim was discovered.  

Contact the Personal Injury Lawyers at Tierney Stauffer LLP for Advice on Medical Malpractice Claims

At Tierney Stauffer LLP, we know how overwhelmed you may feel about the prospect of launching a medical or hospital malpractice lawsuit. If you have a valid claim against a medical professional or hospital, you need a strong advocate by your side to fight their insurers and lawyers.
Our personal injury lawyers provide advice to those who believe they have been wronged by medical malpractice. If you have been injured, it is critical to receive expert legal advice to ensure that you meet any applicable deadlines. Contact us at 1-888-799-8057 or reach out online to set up a consultation today.


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