Dimech v. Osman contains a useful summary of the limitation of claims for non-pecuniary losses arising from a motor vehicle accident:
 Under s. 4(1) of the Limitations Act, 2002 a person loses the right to sue for a claim two years after she “discovers” the claim. Under s. 5(2) of the Limitations Act, 2002 a plaintiff injured in a car accident will be presumed to have discovered her claim on the day of the accident unless she proves that she did not discover the claim that day and that a reasonable person with her abilities and in her circumstances would not have discovered the claim until a later time.
 While one might normally think that being injured in a car accident automatically gives one a claim or the right to sue, that is not necessarily the case. Under s.267.5(5) of the Insurance Act, RSO 1990, c I.8 a person injured in a car accident in Ontario can only sue for non-pecuniary losses if the accident caused her to suffer “permanent serious impairment of an important physical, mental or psychological function.” This is commonly referred to as the “threshold”. If a plaintiff cannot prove that her injuries meet the threshold, her claim for non-pecuniary loss will be dismissed.
 While a plaintiff can sue for pecuniary loss without meeting the threshold, case law provides that for the limitation period to commence in Ontario in relation to a motor vehicle accident lawsuit in which both pecuniary
and non-pecuniary damages are claimed, the plaintiff must have known or ought reasonably to have known that she could likely meet the threshold so as to have the right to sue. In Ioannidis v. Hawkings 1998 CanLII 14822 (ON SC), Justice Langdon held that for the two-year limitation period to start running, there must be,
…a sufficient body of evidence available to be placed before a judge that, in counsel’s opinion, has a reasonable chance of persuading a judge, on the balance of probabilities that the injury qualifies.
 The question of when the limitation period commences is a question of fact. See: Farhat v Monteanu, 2015 ONSC 2119 (CanLII), at para. 33. It requires a finding of a date when a plaintiff or her lawyer knew or ought reasonably to have known that she had a reasonable chance to prove that she suffered permanent serious impairment of an important physical, mental or psychological function as a result of the car accident.
The decision also provides an example of the consequences of failing to adduce the evidence material to the limitation of these claims:
 There is no evidence from Mr. Bekiaris as to whether he, as the plaintiff’s counsel, had formed an opinion during the 37-day pre-limitation period window that the plaintiff had a reasonable chance of persuading a judge that his injuries would meet the threshold. I offered Mr. Bekiaris an opportunity to consider refraining for acting as counsel on this motion both due to this evidentiary issue and in consideration of the fact that if the defendants succeed in having this action dismissed, Mr. Bekiaris could possibly face a claim for having missed the limitation period. He determined to proceed as counsel.
 With no evidence from counsel, and no evidence of any contemporaneous prognosis from a doctor, I am left to try to determine by inference whether the plaintiff or his counsel ought reasonably to have known that his injuries reasonably could have met the threshold during the 37-day pre-limitation period window.
 The defendants argue that with the burden lying on the plaintiff to prove that he could not reasonably have discovered his claim in the 37-day pre-limitation period window, it was incumbent upon him to adduce evidence to show that he or his counsel acted with diligence by asking a doctor for a prognosis. The defendants argue that the plaintiff has failed to prove that he asked any doctor whether his injuries were likely to permanently seriously impair an important function right up to the time that the claim was issued. As such, he cannot meet his burden to show that he acted with diligence as required to rebut the presumption in s. 5(2) of the Limitations Act, 2002. Like the plaintiff, the defendants have adduced no evidence to establish that a reasonable person, in the first 37 days after this type of accident, suffering injuries like those of the plaintiff, would likely know that he or she is likely to meet the threshold. There is no expert prognosis. There is no evidence about whether in the 37-day pre-limitation period window the plaintiff’s counsel ought to have concluded that he had a sufficient body of evidence to provide a reasonable chance of persuading a judge that the plaintiff’s injuries will meet the threshold.
 In my view, the defendants have not met their evidentiary burden to allow me to fairly and justly adjudicate the limitation period issue summarily. While there may perhaps be cases where a plaintiff’s injuries are so severe that they can confidently be said to meet the threshold from day one, I cannot tell if this is such a case. The defendants have given me the plaintiff’s medical records. But I have nothing to allow me to draw an inference that the plaintiff or his lawyer ought to have concluded in the first 37 days after the accident that the injuries met or were likely to meet the threshold at some time in future. Similarly, while I was able to conclude at first instance in Yasmin that the plaintiff had not diligently pursued a claim on the facts, I have nothing to allow me to reach the same conclusion here and now. I do not know if a reasonable patient 37 days into treatment ought to have been asking his doctors for long term prognoses about serious impairment of important functions. Neither is there any evidence before me to let me weigh or conclude whether a reasonable personal injury lawyer ought to have been seeking reports from the doctors about threshold issues within the 37-day pre-limitation period window.