There is a point that confuses many doctors about cases that allege a failure to diagnose. These are ones in which the patient is healthy but is still suing over the care based on the possibility that they might get sick in the future. How is it possible for a plaintiff to do that?

Let’s say that a doctor is sued by a patient who claims that a mammogram that the doctor read 2 years ago actually showed a small early cancer that was not diagnosed. The cancer is now stage 2B and she’s alleging that she would’ve been stage 1 when the cancer was found. She sues for all the additional treatment that she had to undergo due to her delayed diagnosis. But even though she’s currently cancer free, she also alleges a decrease in her chance to survive. That her cancer might recur is only a possibility and people cannot sue over possibilities.

This is called “speculative damages.” We disallow them, but in this case, she’s not suing for future damage. She’s suing for a present one that has already attached the loss of a substantial chance to be cured. We call this the “loss of chance” doctrine, which dates to 1867. In 1966, the fourth circuit stated that when a defendant’s negligent action or inaction has effectively terminated a person’s chance of survival, it does not lie in the defendant’s mouth to raise conjectures as to the measure of the chances that he’s put beyond the possibility of realization.

Courts Separating Causation from Damages

The rule used to be that the pre-negligence survival had to be more likely than not. In other words, over 50% below that level, any harm that the plaintiff suffered was attributed to their disease, even if the doctor was held to have been negligent. What this came down to, though, was that negligent physicians who happened to have been negligent on people with worse illness were protected. Courts began to separate causation from damages.

This changed the analysis from the preponderance of the evidence, the greater than 50% standard that we use to determine if there’s negligence in the first place, to one of pure damages. The loss of chance for a better outcome or a cure is now gradable on its own value. Just as, for example, the loss of a chance to make a living is due to the malpractice.

When there is a treatment failure after a negligent act, it’s likely that jurors, who have faith in modern medicine and who believe that early detection leads to cure, will conclude that the harm must have occurred solely because of the negligence. So actual limitations in the given case such as the inherent aggressiveness of the disease or the patient’s own physical limitations should, therefore, be made clear to the jury.

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