I refer to my earlier posting on the first instance decision. The appeal was dismissed unanimously with respect to the ground of “lost chance”, but her Honour Margaret Wilson AJA dissented on causation.
The review by his Honour Martin J in respect of lost chance and causation has been repeated in full.
 Margaret McMurdo P: I agree with Martin J’s reasons for dismissing this appeal but wish to give some supplementary reasons.
A loss of a chance?
 The judge concluded from Dr Garrahy’s evidence that, if Ms Papa had been referred to him at that time, he was available to attend on her and would have treated her as he described. Had she undertaken this treatment, her risk of suffering a thromboembolism would have been ameliorated and it was probable that she would not have suffered a stroke on 1 March 2002. His Honour concluded on the balance of probabilities that SNPL’s failure to advise Ms Papa and Dr Powell appropriately by about 22 February 2002 was a breach of its duty of care to Ms Papa which was causative of her suffering a stroke on 1 March 2002.
 I cannot accept SNPL’s contention that Ms Papa’s claim was for the loss of a chance of a better medical outcome, and that the judge’s conclusion as to liability was contrary to the principle re-affirmed recently by the High Court in Tabet v Gett. The judge found on the balance of probabilities that, had SNPL given advice to Ms Papa and Dr Powell consistent with its duty of care to Ms Papa by 22 February 2002, Dr Powell would have referred her to her cardiologist, Dr Garrahy; she would have taken the treatment he recommended; her INR would have been raised to her therapeutic range; and she would not have suffered a stroke. These were certain findings, established on the balance of probabilities, consistent with the common law requirement that courts must reduce to legal certainty questions to which conclusive answers cannot be given: see Malec v J C Hutton Pty Ltd. This has the result that, when loss or damage is proved to have been caused on the balance of probabilities by a defendant’s act or omission, the plaintiff recovers the entire loss suffered, even if there was a forty-nine percent chance of it not occurring. Kiefel J in Tabet referred to this requirement as the “all or nothing rule”. SNPL’s contention that the primary judge’s findings on liability offended the principle in Tabet v Gett are baseless.
 Margaret Wilson AJA: I respectfully adopt the President and Martin J’s summaries of the facts and the trial judge’s findings.
 I agree with their Honours that the trial judge was correct in not characterising the respondent’s claim as one for the loss of a chance of a better medical outcome. I also agree with their Honours that the trial judge’s finding that the appellant breached its duty of care to the respondent was open on the evidence, although I wish to make some further observations in relation to that.
 I respectfully disagree with the President and Martin J’s conclusion in relation to causation. In my view the respondent failed to prove that the appellant’s breach of duty caused her to suffer a thrombotic stroke on 1 March 2002. For this reason, I would allow the appeal.
 On the appellant’s reasoning, the learned trial judge has, notwithstanding his clear disavowal of the claim for loss of a chance, nevertheless actually found for the respondent on that basis.
 In order to determine whether the learned trial judge made the error complained of it is appropriate to consider the manner in which his Honour assessed the evidence and whether he did so in accordance with the accepted test for whether compensable damage has occurred.
 In Gregg v Scott Lord Nicholls of Birkenhead described the test in the following way:
“ In the normal way proof of the facts constituting actionable damage calls for proof of the claimant’s present position and proof of what would have been the claimant’s position in the absence of the defendant’s wrongful act or omission. As to what constitutes proof, traditionally the common law has drawn a distinction between proof of past facts and proof of future prospects. A happening in the past either occurred or it did not. Whether an event happened in the past is a matter to be established in civil cases on the balance of probability. If an event probably happened no discount is made for the possibility it did not. Proof of future possibilities is approached differently. Whether an event will happen in the future calls for an assessment of the likelihood of that event happening, because no one knows for certain what will happen in the future.”
 In Tabet v Gett, Gummow A-CJ identified the issue for the High Court in this way:
“ In the present case, the Court of Appeal considered, and properly so, that it could only be for this Court “to reformulate the law of torts to permit recovery for physical injury not shown to be caused or contributed to by a negligent party, but which negligence has deprived the victim of the possibility (but not the probability) of a better outcome”.
 These reasons will seek to demonstrate that the reformulation of which the Court of Appeal spoke should not be made, and that the appeal to this Court must fail. However, this outcome will not require acceptance in absolute terms of a general proposition that destruction of the chance of obtaining a benefit or avoiding a harm can never be regarded as supplying that damage which is the gist of an action in negligence.
 The appellant sought to stigmatise the respondent’s case as being that, because the likelihood of this better outcome was less than 50 per cent, it followed (a) that on the balance of probabilities the appellant would still have suffered as much as she did, and therefore (b) the chance, prospect or opportunity had no worth.
 However, if the likelihood of a better outcome had been found to be greater than 50 per cent then on the balance of probabilities the appellant would have succeeded, not failed, on the main branch of her case in negligence. The question of principle thus becomes whether the law permits recovery in negligence on proof to the balance of probabilities of the presence of something else, namely a chance, opportunity or prospect of an outcome the eventuation of which, however, was less than probable.”
 Hayne and Bell JJ referred to Gregg v Scott when they said:
“ For the purposes of the law of negligence, ‘damage’ refers to some difference to the plaintiff. The difference must be detrimental. What must be demonstrated (in the sense that the tribunal of fact must be persuaded that it is more probable than not) is that a difference has been brought about and that the defendant’s negligence was a cause of that difference. The comparison invoked by reference to ‘difference’ is between the relevant state of affairs as they existed after the negligent act or omission, and the state of affairs that would have existed had the negligent act or omission not occurred.” (emphasis added)
“ As Gummow A-CJ explains, to accept that the appellant’s loss of a chance of a better medical outcome was a form of actionable damage would shift the balance hitherto struck in the law of negligence between the competing interests of claimants and defendants. That step should not be taken. The respondent should not be held liable where what is said to have been lost was the possibility (as distinct from probability) that the brain damage suffered by the appellant would have been less severe than it was.”
 Where it is found that a particular event was more likely than not to have occurred, then the law raises that finding to a certainty. As Kiefel J (with whom Hayne, Crennan and Bell JJ agreed on this point) said:
“ Once causation is proved to the general standard, the common law treats what is shown to have occurred as certain. The purpose of proof at law, unlike science or philosophy, is to apportion legal responsibility. That requires the courts, by a judgment, to “reduce to legal certainty questions to which no other conclusive answer can be given”. The result of this approach is that when loss or damage is proved to have been caused by a defendant’s act or omission, a plaintiff recovers the entire loss (the “all or nothing” rule).
 When an issue is proved to the general standard the court treats the damage caused as certain, thus giving rise to the all-or-nothing rule of recovery. The rule is strongly criticised by those who favour acceptance of loss of chance as damage. However, the rule reflects the certainty that the law considers to be necessary when attributing legal responsibility for harm caused. To replace it with a rule which limits damages awarded according to the degree of probability of causation has its own limitations. It would suggest, if not require, a degree of precision in the assessment of probabilities which is not part of the more liberal, common sense, approach presently undertaken. And, as Baroness Hale of Richmond observed in Gregg v Scott, proportionate recovery cuts both ways.” (emphasis added)
 The appellant’s contentions are not supported by an analysis of his Honour’s reasons. He did compare “the relevant state of affairs as they existed after the negligent act or omission, and the state of affairs that would have existed had the negligent act or omission not occurred”. He then found, on the balance of probabilities that, had SNPL given the respondent the appropriate advice, then certain events would have occurred and she would not have suffered the stroke. The complaint made by the appellant is more properly categorised as a complaint about the way in which the learned trial judge went about the fact finding exercise. It is argued that he could not have come to the conclusion he did had he taken into account certain evidence, namely, that which related to the possibility of Ms Papa suffering a haemorrhage. That is considered later in these reasons, but, assuming the appellant’s contention is correct, that does not mean that his Honour’s finding was based on the loss of a chance.
Liability finding contrary to the evidence – Grounds 2,3 and 4
 Under this heading the appellant attacks the following findings made by his Honour:
“ Whilst it was not, for the reasons I have given above, appropriate for the defendant itself to instigate alternative treatment with Clexane or Heparin, it seems to me, in the circumstances of this case, that when advising the GP to undertake or investigate management of the risks then faced by the plaintiff, it would have been reasonably appropriate for the defendant at least to raise the prospect of the GP investigating alternative or supplementary forms of anti-coagulation and also to raise the prospect of this needing to be done in consultation with the plaintiff’s cardiologist.
 In reaching this conclusion, I draw not merely on the consistent evidence among the experts as to the desirability of appropriate communication between the Warfarin care haematologist and the patient and the patient’s GP, but also Dr Davidson’s evidence to the effect that not all GP’s are up to date in managing complex anti-coagulation problems and would probably need some guidance. A fortiori in a case such as the present, which Dr Rowbotham described as having presented her with a “difficult management problem” because of the need to balance the risks of a thromboembolic event and an haemorrhagic event, and which involved a patient with an artificial mitral valve who in the weeks immediately preceding the persistent sub-therapeutic levels had demonstrated INR instability. In my view, a reasonable Warfarin care provider would have given the kind of advice and guidance to which I referred in para , as part of the guidance expected of and from a specialist Warfarin care service. The giving of this advice and guidance did not involve questions of clinical judgment. By not communicating this advice to the plaintiff and this advice and guidance to her GP, the defendant failed to meet the standard of care required of a reasonable Warfarin care haematologist.” (emphasis added)
 These determinations were based upon, and had been preceded by, these matters:
“ Having regard to the situation of this particular plaintiff, with an artificial mitral valve which of itself dictated caution in respect of the risk of clotting and a recent history of INR instability, and also having regard particularly to the evidence of both Professor Metz and Professor Eikelboom as to the desirability, if not the necessity, to communicate with the patient, I consider that a reasonable Warfarin care haematologist in the position and having the knowledge of the defendant would have contacted the plaintiff:
(a) To advise of the unstable history of INR readings and of the persistent sub-therapeutic levels;
(b) To advise (or at least reaffirm) the risks associated with sub-therapeutic INR readings;
(c) To advise of the approach which was being adopted to incrementally increase dosage levels in an attempt to bring her INR back into range;
(d) To advise the plaintiff that she should consult her G P with respect to management of the risks associated with her sub-therapeutic INR levels.”
 SNPL did not provide any of that advice to the respondent. This part of his Honour’s reasons was not the subject of criticism yet it is the basis upon which the later findings (in  and ) were made.
 The appellant submits that there was no basis for the learned trial judge to conclude that it had a duty to consider, and to advise Ms Papa or Dr Powell, that they investigate alternative or supplementary forms of anti-coagulation. This, it was said, is the inevitable conclusion to be drawn where there were no suitable alternatives available. It is on that point that this part of the appellant’s case turns, but before I consider whether there was evidence to support his Honour’s conclusions I will briefly refer to the authorities which deal with the duty of care of a medical practitioner.
 In Rogers v Whitaker the duty was explained in this way:
“The law imposes on a medical practitioner a duty to exercise reasonable care and skill in the provision of professional advice and treatment. That duty is a ‘single comprehensive duty covering all the ways in which a doctor is called upon to exercise his skill and judgment’; it extends to the examination, diagnosis and treatment of the patient and to the provision of information in an appropriate case. It is of course necessary to give content to the duty in the given case.
The standard of reasonable care and skill required is that of the ordinary skilled person exercising and professing to have that special skill …”
 The content of the duty of care to be observed is not static – it changes with the particular circumstances:
“The duty of a medical practitioner to exercise reasonable care and skill in the provision of professional advice and treatment is a single comprehensive duty. However, the factors according to which a court determines whether a medical practitioner is in breach of the requisite standard of care will vary according to whether it is a case involving diagnosis, treatment or the provision of information or advice; the different cases raise varying difficulties which require consideration of different factors. Examination of the nature of a doctor-patient relationship compels this conclusion. There is a fundamental difference between, on the one hand, diagnosis and treatment and, on the other hand, the provision of advice or information to a patient. In diagnosis and treatment, the patient’s contribution is limited to the narration of symptoms and relevant history; the medical practitioner provides diagnosis and treatment according to his or her level of skill. … Whether a medical practitioner carries out a particular form of treatment in accordance with the appropriate standard of care is a question in the resolution of which responsible professional opinion will have an influential, often a decisive, role to play …” (emphasis added)
 In order to determine the content of the duty in a particular case expert evidence as to the relevant professional practice and opinion is relevant to, but not conclusive of, that content. In this case there was a substantial amount of such evidence and, on some important areas, there were differences of opinion or of emphasis.
 These principles were noted by the learned trial judge as well as the obligation to consider these matters prospectively and not with the benefit of hindsight. As Hayne J said in Vairy v Wyong Shire Council  HCA 62; (2005) 223 CLR 422:
“ The central issue in the appeal is whether the Council breached a duty of care it owed to the appellant by not erecting one or more signs warning against, or prohibiting, diving from the rock platform. Resolving that question, a question of fact, hinges critically upon recognising that what has come to be known as the “Shirt calculus” is not to be undertaken by looking back at what has in fact happened, but by looking forward from a time before the occurrence of the injury giving rise to the claim. …
 Again, because the inquiry is prospective, it would be wrong to focus exclusively upon the particular way in which the accident that has happened came about. In an action in which a plaintiff claims damages for personal injury it is inevitable that much attention will be directed to investigating how the plaintiff came to be injured. The results of those investigations may be of particular importance in considering questions of contributory negligence. But the apparent precision of investigations into what happened to the particular plaintiff must not be permitted to obscure the nature of the questions that are presented in connection with the inquiry into breach of duty. In particular, the examination of the causes of an accident that has happened cannot be equated with the examination that is to be undertaken when asking whether there was a breach of a duty of care which was a cause of the plaintiff’s injuries. The inquiry into the causes of an accident is wholly retrospective. It seeks to identify what happened and why. The inquiry into breach, although made after the accident, must attempt to answer what response a reasonable person, confronted with a foreseeable risk of injury, would have made to that risk. And one of the possible answers to that inquiry must be “nothing”.
 When a plaintiff sues for damages alleging personal injury has been caused by the defendant’s negligence, the inquiry about breach of duty must attempt to identify the reasonable person’s response to foresight of the risk of occurrence of the injury which the plaintiff suffered. That inquiry must attempt, after the event, to judge what the reasonable person would have done to avoid what is now known to have occurred. Although that judgment must be made after the event it must seek to identify what the response would have been by a person looking forward at the prospect of the risk of injury.” (emphasis added)
Brisbane Barrister – David Cormack