Volume 196 - Issue 3
Legal clarification of “loss of chance of a better outcome” in Australia
Authors: Neera Bhatia and James Tibballs
Med J Aust 2012; 196 (3): 167-168. || doi: 10.5694/mja10.10225
Published online: 20 February 2012
Published online: 20 February 2012
A High Court of Australia ruling has reinstated the need for patients to prove causation of injury. The tort (ie, civil wrong) of medical negligence has recently changed, to the advantage of doctors. By its judgment in the case of Tabet v Gett in 2010....
A High Court of Australia ruling has reinstated the need for patients to prove causation of injury
The tort (ie, civil wrong) of medical negligence has recently changed, to the advantage of doctors. By its judgment in the case of Tabet v Gett in 2010 (Box 1),1 the High Court of Australia has effectively removed the concept of “loss of chance” (Box 2) as a possible course of action by patients against doctors. The doctrine of loss of chance had enabled a patient to obtain partial compensation for injury without having to prove causation.6
The decision of the High Court of Australia confirms that medical negligence claims must be based on actual measurable harm or injury; whereas in loss of chance, the harm is speculative and immeasurable. Had this decision not been made, the implications for doctors, hospitals and insurance providers may have been vast. While the traditional legal nature of medical negligence has been reinstated, law, like medicine, evolves. It is possible that loss of chance may be reconsidered in the future, as indicated in the following examples of legal discussion.
In Tabet v Gett,1 Acting Chief Justice Gummow conceded that the all or nothing outcome based on the balance of probabilities leads to “rough justice” — a doctor who negligently causes 51% of an injury must pay 100% compensation, while a patient gets nothing if the doctor was responsible for (only) 49% of the injury. Neither outcome appears fair. However, the legal rationalisation for retaining the probability of causation is that it represents
... a balance between the competing interests of the parties, [whereas] the substitution of the loss of a chance as the actionable damage represents a shift in that balance towards claimants.1
Furthermore, undesirably, although loss of chance may
especially with respect to medical treatment ... assist in the maintenance of standards where there is a less than even chance of a cure ... any such potential benefit to the public weal [good fortune] has to be weighed against, for example, the prospect of “defensive medicine” with emphasis upon costly testing procedures in preference to a sequential deductive approach to diagnosis and treatment.1
... there is no reason in principle why loss of a chance ... should not constitute damage for the purposes of the law of tort where no other loss is involved.7
... the chance of obtaining a benefit or avoiding a harm has value in itself that is entitled to legal protection ... destruction of this chance ought to be regarded as damage giving rise to an actionable tort.8
Reema Tabet, aged 6, claimed that delayed diagnosis of a medulloblastoma caused her brain damage that was equivalent to compensation of $6.1 million. She had presented with headaches, nausea, vomiting and a right pupil unreactive to light after a bout of chickenpox. A diagnosis of viral meningitis or encephalitis was considered. A lumbar puncture was performed but was followed by an episode of decerebrate posturing, possibly due to a seizure or “coning”. A computed tomography (CT) scan was performed the next day, and the tumour was diagnosed. Miss Tabet’s claim was that if a CT scan had been performed earlier, the tumour would have been discovered and the lumbar puncture and subsequent brain damage would have been averted.
In initial proceedings, the Supreme Court of New South Wales ruled that 25% of the brain damage was caused by the decerebrate episode (but not due to the lumbar puncture), while 75% was caused by residual medulloblastoma, its seeding and hydrocephalus, and by non-negligent incomplete surgical removal and subsequent radiotherapy.2 Dr Gett was found negligent for not performing a CT scan earlier, but this was ruled not to be the cause of the brain damage. Nonetheless, the judge estimated that Miss Tabet had lost a 40% chance of a better outcome, and therefore could have avoided 40% of her brain damage. She was awarded damages of $610 000 (40% of 25% of $6.1 million).
Dr Gett appealed, while Miss Tabet cross-appealed.3 Both claimed that the doctrine of “loss of chance” was wrong, but for different reasons. Dr Gett challenged the finding of negligence, and the application and calculation of loss of chance, claiming lack of scientific and epidemiological evidence to support it. Miss Tabet claimed that the doctor’s negligence caused all of her brain injury and that she was entitled to $6.1 million. Although the Court of Appeal found that there was no error in the previous ruling that Dr Gett had been negligent by failing to order a CT scan, it reconsidered the application of loss of chance. It conceded that, being bound by the decision in the earlier case of Rufo v Hosking,4 the judge had been obliged to award damages even when the doctor’s negligence contributed less than 51% to the injury. Indeed, it speculated that negligence contributed only 15% to the injury. However, the Court of Appeal ruled that the decision in Rufo v Hosking4 was “plainly wrong” and hence rejected Miss Tabet’s claim.3 The reasons for rejection were (among others) that loss of chance came from no recognised stream of authority; it did not consider the difficulties, complexities and limitations of judgments; and it was inconsistent with the nature of harm and the requirement to establish causation on the balance of probability that is currently expressed in various state Civil Liability Acts. Miss Tabet subsequently appealed unsuccessfully to the High Court of Australia.1
“Loss of chance” cases typically involve a doctor negligently failing to diagnose or treat an illness. A patient claims damages for a lost chance of a better outcome. The patient’s “loss” is estimated by comparing the actual outcome to an outcome that could be foreseen if negligence had not occurred. The percentage loss is then calculated, and the patient is awarded that percentage of full compensation.
Although negligence and existence of a chance of a better outcome must still be proven on the balance of probabilities, the patient does not need to prove that the negligence caused the harm. It is not necessary to show that “but for” the doctor’s action, the outcome would have been better. In essence, the concept of loss of chance relates to “... whether, on the balance of probabilities, the breach of duty deprived the plaintiff [the patient] of between a 1% and 50% chance of a better clinical outcome”.5
Competing interests
No relevant disclosures.
References
- Tabet v Gett [2010] HCA 12. 0_i1115640
- Tabet v Mansour [2007] NSWSC 36. 0_i1115642
- Gett v Tabet [2009] NSWCA 76. 0_i1115644
- Rufo v Hosking [2004] NSWCA 391. 0_i1115646
- Bowen T, Saxton A. The changing face of causation — denial of damages for possibilities and lost chances. Aust Health Law Bull 2009; (May): 117-122. 0_i1115650
- Tibballs J. Loss of chance: a new development in medical negligence law. Med J Aust 2007; 187: 233-235. 0_i1115651
- Naxakis v Western General Hospital [1999] HCA 22. 0_i1115653
- Fischer DA. Tort recovery for loss of chance. Wake Forest Law Rev 2001; 36: 605. 0_i1115655
Provenance: Not commissioned; externally peer reviewed.