New South Wales Court of Appeal CITATION : A Mazzzaferro & Riverstone Pty Ltd t/as Family Medical Centre v Vozzo & 5 Ors [2004] NSWCA 271 HEARING DATE(S) : 04/08/04 JUDGMENT DATE : 5 August 2004 JUDGMENT OF : Mason P at 79; Handley JA at 80; Ipp JA at 2 DECISION : Appeal dismissed with costs. CATCHWORDS : WORKERS' COMPENSATION - Doctor contracted HIV and AIDS in the course of medical employment - Where precise date and occurrence of infection not identified - Where multiple employers - Causation - Where expert evidence given regarding the possible range of dates of infection - Whether any evidence supported finding of trial judge that employment by the appellants was a cause of injury - Whether evidence of arithmetic probability can sustain a finding on the balance of probabilities - Sufficiency of evidence - Whether question of fact or law - Whether absence of Reasons. D LEGISLATION CITED : Compensation Court Act 1984 (NSW), s 32 Workers Compensation Act 1987 (NSW), ss 36, 37, 40 Ambulance Service of New South Wales v Daniel (2000) 19 NSWCCR 697 Azzopardi v Tasman UEB Industries [1985] 4 NSWLR 139 Belmont Night Patrol Pty Ltd v Woolworths Ltd [2004] NSWCA 235 Bendix Mintex Pty Ltd v Barnes (1997) 42 NSWLR 307 E M Baldwin & Son Pty Ltd v Plane [1999] Aust Torts Reports 81-499 EMI (Australia) Ltd v Bes [1970] 2 NSWR 238 CASES CITED : Fernandez v Tubemakers of Australia Ltd [1975] 2 NSWLR 190 ICI Australia Operations Pty Ltd v Walsh (1997) 15 NSWCCR 279 McPhee v S Bennett Ltd (1935) 52 WN (NSW) 8 Rose v Abbey Orchard Property Investments Pty Ltd [1987] Aust Torts Reports 80-121 Seltsam Pty Ltd v McGuiness (2000) 49 NSWLR 262 Tenax Steamship Co Ltd v The Brimnes (Owners) [1975] QB 929 Wallaby Grip (BAE) Pty Limited (In Liq) v Macleay Area Health Service (1998) 17 NSWCCR 355 Angelo Mazzaferro & Riverstone Pty Ltd t/as Family Medical Centre (Appellants) Franck Anthony Vozzo (First Respondent) St Vincents Hospital Sydney Ltd (Second Respondent) PARTIES : Liverpool Hospital - Liverpool Area Health Service (Third Respondent) Griffith Base Hospital - Greater Murray Health Centre (Fourth Respondent) Camden Hospital - Macarthur Health Service (Fifth Respondent) Sutherland Hospital - Sutherland Eastern Sydney Area Health Centre (Sixth Respondent) FILE NUMBER(S) : CA 40048/04 A J Poulos QC/P Perry (Appellants) COUNSEL : P Blacket SC/R Hanrahan (First Respondent) B R Ferrari SC/E Techera (Second, Third, Fourth, Fifth Respondents) Rankin Nathan (Appellants) SOLICITORS : Morgan Ardino & Co (First Respondent) Hunt & Hunt Lawyers (Second, Third, Fourth, Fifth Respondents) LOWER COURT Compensation Court JURISDICTION : LOWER COURT CC 13543/02 FILE NUMBER(S) : LOWER COURT Hughes CCJ JUDICIAL OFFICER : IN THE SUPREME COURT OF NEW SOUTH WALES COURT OF APPEAL CA 40048/04 CC 13543/02 MASON P HANDLEY JA IPP JA Thursday 5 August 2004 ANGELO MAZZAFERRO & RIVERSTONE PTY LTD T/AS FAMILY MEDICAL CENTRE v FRANCK ANTHONY VOZZO & 5 ORS Judgment 1 MASON P: I will ask Ipp JA to give the first judgment. 2 IPP JA: This is an appeal against orders made by Hughes CCJ pursuant to ss 36, 37 and 40 of the Workers' Compensation Act 1987 (NSW). His Honour ordered the appellants to pay the first respondent ("Dr Vozzo") workers compensation at the maximum statutory rate for a man with a dependent wife and three dependent children "from 15 December 2000 to 15 June 2001 pursuant to s 36, then 16 June 2001 to 1 March 2002 pursuant to s 37 and then from 12 March 2002 to 11 March 2003 pursuant to s 40 and then from 12 March 2003 to date and continuing pursuant to s 37". The appellants appeal against these orders. 3 The judge, after reviewing the evidence, said: "I am satisfied that on the balance of probabilities the infection more likely than not occurred in the period [Dr Vozzo] was employed by [the appellants]". This is the finding that is challenged on appeal. 4 Section 32 of the Compensation Court Act 1984 (NSW) provides that an appeal against a decision of the Compensation Court can only be challenged on appeal "in point of law". In Azzopardi v Tasman UEB Industries Ltd [1985] 4 NSWLR 139 Glass JA (with whom Samuels JA agreed) at 155 followed McPhee v S Bennett Ltd (1935) 52 WN (NSW) 8 where Jordan CJ (with whom Davidson and Stephen JJ agreed) said (at 9): "The question whether there is any evidence of a particular fact is also a question of law … But if there is evidence of the fact, the question whether that evidence ought to be accepted in whole or in part, or ought to be accepted as sufficient to establish the fact, is itself a question of fact and not a question of law, unless, of course, there is some law which provides that the particular evidence, when given, is to be taken to establish the fact." 5 Mr Poulos QC who, together with Mr Perry, appeared for the appellants pointed out, however, that in Ambulance Service of New South Wales v Daniel (2000) 19 NSWCCR 697 Hodgson CJ in Eq (with whom Sheller and Beazley JJA agreed) said (at 711) that in Azzopardi Glass JA distinguished between "the situation where the finding of fact in question is made in favour of a person bearing the onus of proof, and the situation where the finding of fact is made against the person bearing the onus of proof". His Honour concluded (at 713) that, consistently with Azzopardi, "the correct question, in relation to a matter where a finding has been made in favour of a person bearing the onus, is whether or not the finding could properly be made on the evidence, if fully accepted". In other words, his Honour held that where a finding of fact is made in favour of a person bearing the onus of proof, the question for an appellate court is not whether there is any evidence at all on the point, but rather whether the evidence on the point is sufficient, in the sense that it is evidence which, if fully accepted, could properly base the finding of fact. 6 I have reservations about this view of the reasons of Glass JA in Azzopardi and would observe that it appears to be contrary to McPhee v S Bennett Ltd. In the light of the conclusion to which I have come, however, on the facts of the case it is not necessary for me to express any firm opinion on this question. 7 I turn now to the evidence led at the trial. 8 Dr Vozzo graduated with Honours as a medical practitioner. He was then chosen to do his residency in the Professorial Unit at St Vincent's Hospital, Darlinghurst, the second respondent. He began his internship there on 1 January 1982 and remained employed by St Vincent's for a period of two years until 1984. 9 During this period of two years, St Vincent's sent Dr Vozzo to work at other of the respondent hospitals. He worked at Liverpool Hospital (the third respondent) for about ten weeks in early 1982 and for a further 12 weeks at the start of 1983. He worked at Griffith Base Hospital (the fourth respondent) for ten weeks in 1982 and in Camden Hospital (the fifth respondent) for 12 or 13 weeks in 1983. 10 In 1984 and 1985 Dr Vozzo worked at Sutherland Hospital (the sixth respondent). From January 1986 to August 1986 Dr Vozzo was employed as a registrar in casualty at Liverpool Hospital. 11 From mid-August 1986 to December 2000, a period of some fourteen years, Dr Vozzo was employed as a medical practitioner by the appellants. 12 In mid-1994 Dr Vozzo underwent a blood test and was found to be HIV positive. In 2000 he was diagnosed as suffering from AIDS. By the time of the trial, Dr Vozzo was a patient at St Vincent's Hospital, suffering from "encephalitis due to HIV and a secondary viral brain infection, cytomegalovirus". 13 An important question at the trial concerned the time at which Dr Vozzo was infected with the HIV virus. 14 Professor Carr, an expert in the management of HIV infection and its complications, said in a report dated 14 May 2002 that Dr Vozzo "would have been infected for over five to ten years [prior to July 1994], although this is obviously speculation in the absence of prior results". In cross-examination Professor Carr explained that in saying "over five to ten years" he meant "between five and ten years". He also said that the infection would be "closer to ten than to five", in other words, closer to 1984 than 1989. Nevertheless, he accepted that the period could be less than five or more than ten years. 15 In his examination in chief Professor Carr gave the following evidence: "A normal CD4 count is between about 500 and 1500 so let's for averages say it's about 1,000 although it can be very variable. In a population of adults infected with HIV the average decline in CD4 count is about 50 cells a year, give or take, so if 500 is normal and 100 or less is life threatening then you could see that it is about ten years between infection and severe illness, AIDS. Given that his count was 230 at diagnosis in 1994, on averages he would've been infected for five to ten years. It could be either side of that but it would be unlikely." 16 In cross-examination Professor Carr said that it was "quite conceivable" that Dr Vozzo had been infected for longer than ten years and repeated that the date of infection would be "closer to ten than five". 17 Despite the variations to which I have referred, the thrust of Professor Carr's evidence as a whole is that, when assessing the date of infection by working back from the date of infection with the HIV virus, Dr Vozzo was likely to have been infected between five to ten years prior to being diagnosed as suffering from the HIV virus. This view was consistent with the evidence of Dr Bodsworth, another expert in the field, who said: "Dr Vozzo tested positive to HIV on blood taken on 1st July 1994. This was his first test so it is impossible to determine how long he had been infected prior [to] this date. Specific testing of his immune system shortly after diagnosis revealed a degree of immune suppression consistent with HIV being present for a number of years, perhaps five to ten." 18 When it was put to Professor Carr that it would be possible to fix the date of infection substantially earlier than 1984, he replied that that was not possible. In explaining why this was the case, he gave a different basis for estimating the date when Dr Vozzo was infected with the HIV virus. One of the reasons for his view that the date of infection could not have been substantially earlier than 1984 was that "the population evidence is that the interval between infection and AIDS is eight to ten years in the absence of treatment and between AIDS and death is another two, so that 50% of people who get infected have a severe illness within ten years". In other words, he was saying that within a relatively short period prior to the eight to ten years from the diagnosis with the "severe illness", most sufferers from such an illness would have contracted the HIV virus. Applying that to Dr Vozzo's case, he having sustained a serious illness in 2000, there is little chance that he was infected with HIV earlier than 1984 (and the corollary to this is that it is likely that he was infected closer to the latter part of the 1980's rather than the earlier part of the decade). 19 In any event, according to Professor Carr, taking the diagnosis of AIDS as a starting point (and not the diagnosis of HIV), the period in which Dr Vozzo was likely to have been infected (based on "population evidence") was eight to ten years prior to 2000 (that is, from 1990 to 1992). 20 Professor Carr made it clear that the opinions he was expressing as to the period in which infection could have occurred were estimates only. This was necessary as, in his words, the theories applicable "are very hard to apply to an individual". 21 Hughes CCJ found as a fact that Dr Vozzo's infection "was caused by an injury some time between 1984 and 1992". In other words, he took the estimate of 1984 to 1989 based on the five to ten year period prior to diagnosis of HIV infection and extended it to 1992 by reason of Professor Carr's alternative basis which rested on the time prior to diagnosis of AIDS. There was plainly evidence on which his Honour could have made this finding and I do not think that it can be challenged on appeal. 22 It was accepted at the trial that Dr Vozzo was infected with the HIV virus in the course of his employment with his various employers during the relevant period. There was no suggestion that he was infected otherwise than by the virus being transmitted to him through his treatment of an infected patient. Dr Vozzo could only have become infected by cutaneous or mucosal exposure to blood or other body fluids contaminated with HIV. 23 While Dr Vozzo was employed with the appellants, there were instances in which he came into direct contact with the blood of patients. He said: "My fingers and hands would frequently come into contact with blood as a result of venesection and cannulation procedures on patients." This would occur particularly when blood would leak out through the site of a needle injection. He would then press on the site with a cotton ball or some gauze squares for as long as necessary to stop the bleeding. On occasions blood would come up through the wound and through the gauze and make contact directly with his fingers. 24 Often while cleaning wounds he would disturb a clot of blood and the blood would spurt on to his hands, arms or face. It is possible that blood might then have made contact with his eyes, but he was not certain about this. 25 During the process of venesection, blood would be collected into plastic collection tubes with plastic screw tops. The blood from time to time leaked from these tubes and on occasions would get onto Dr Vozzo's hands. 26 Also, while employed with the appellants, Dr Vozzo suffered needle stick injuries. This occurred when he pricked his fingers as he attempted to re-cap needles before disposing of them. He said that such injuries occurred about two or three times a year. 27 Sometimes his hands would come into contact with the blood of patients when he was suturing or otherwise treating their open wounds without wearing gloves. This would occur once or twice each year. 28 Occasionally, he had to insert medication intravenously using a needle and syringe. He would do this by inserting a cannula or "butterfly needle". Sometimes, after inserting the cannula into the vein, the blood would come back into the hollow section of the cannula from the vein and then on to the patient's body. Dr Vozzo would clean the blood by using gauze squares. In attempts to cap the cannula, blood sometimes came on to his hands. He would not always wear gloves while carrying out these procedures. 29 From time to time the skin around Dr Vozzo's fingernails would break and would be pulled back. He said that this occurred about once every six to eight weeks. The cause was the dryness of his skin resulting from frequent hand washing in the course of his work as well as minor trauma sustained to his fingers from time to time at work or at home. Sometimes the skin at the base of his nails was pulled back so far that it would bleed. He would treat this open wound with a bandaid unless the wound was trivial. 30 He also sustained other minor injuries to his hands whilst carrying out gardening, household maintenance or other chores. These included minor cuts to his hands and fingers and involved broken skin and abrasions. These did not prevent him from carrying out his daily work duties. 31 In the period of four years prior to his employment with the appellants (that is, from 1982 to 1986), while he was employed by the respondent hospitals, Dr Vozzo came into contact with the blood of patients in the same way as he did when, later, he was employed by the appellants. 32 Dr Vozzo testified as to specific incidents when he came into contact with the blood of patients. He recalled one incident in about 1983 at Liverpool Hospital when he applied his right thumb to stop a patient bleeding profusely from the back of his hand. At that time Dr Vozzo had a 1 cm cut on his thumb. Another incident occurred in 1985 whilst he was employed as a resident doctor at Sutherland Hospital. He attempted to stop a patient bleeding from a stab wound in the neck. Although he was wearing gloves the patient's blood came into direct contact with his skin. 33 On other occasions blood from patients with profuse nose bleeds would come into contact with his skin. Whilst working at the various respondent hospitals he would regularly treat known intravenous drug addicts. Sometimes he would have to insert a cannula in their veins in order to take blood and on occasions their blood would come into contact with his skin. Other instances of blood coming into contact with Dr Vozzo occurred when he was treating scalp wounds. All these instances took place whilst Dr Vozzo was employed with the respondent hospitals. 34 Hughes CCJ considered several factors before concluding Dr Vozzo was infected while in the appellants' employ. Some of these favoured Dr Vozzo, others favoured the appellants. 35 The judge said: "[T]he prevalence of the HIV virus in the population must have increased between 1982 and some time late in the 1990's. The best evidence for that and I do not think it is controversial is that there had been an increase in diagnosed cases." 36 Mr Poulos submitted that there was no foundation for this observation. 37 While Professor Carr was testifying, the judge said: "[T]he likelihood of anyone having AIDS in 1983 is lower than it is now or subsequent. There is nothing controversial about that is there." Trial counsel for the appellants replied: "No, nothing at all." 38 Mr Poulos submitted that, as counsel was replying to a question about AIDS and not the HIV virus, counsel's reply did not justify his Honour's finding that the prevalence of the HIV virus in the population must have increased between 1982 and some time late in the 1990's. 39 In context, however, it is plain that at the time this exchange took place, the judge and counsel were using the terms "AIDS" and "HIV" interchangeably. For example, immediately prior to the judge's question about AIDS in 1983, he referred to Professor Carr's evidence that St Vincent's Hospital had a "higher population of HIV infected people" than Liverpool Hospital. Counsel for the respondent hospitals replied "I think the Doctor said that if the patient had HIV or AIDS". Then followed the judge's question and the reply by counsel for the appellants. 40 In these circumstances, I am not persuaded that the judge erred in the particular finding he made. 41 The second factor to which Hughes CCJ had regard is what he described as "the susceptibility of the population". He said that there was evidence that the population most at risk were those who "have homosexual practises or drug addicts". The judge observed that an expert had said, "95% of those suffering from HIV were people at risk". His Honour remarked that the people more at risk "were and are more likely to be concentrated in the areas around St Vincent's Hospital than they are at Helensburgh and places in the south". This is a factor that tended to support the appellants (the appellants' hospital being in Helensburgh). 42 The third factor the judge took into account was expressed by him as follows: "I asked the Professor were there more HIV cases from hospital [sic], being a more dangerous place than a private practice and he agreed with that too." This, again, is a factor that tends to support the appellants. 43 The fourth factor was that Dr Vozzo worked for the appellants for a period longer than the periods for which he worked for the other respondents. There can be no challenge to this fact. If the material period is taken as being from 1984 from 1992 (as the judge found), Dr Vozzo worked for 32 months of this period at the respondent hospitals and 64 months for the appellants. This is a factor that tends to support Dr Vozzo. 44 The fifth factor was that the only known HIV patients treated by Dr Vozzo were patients treated while he was employed with the appellants. This factor tends to support Dr Vozzo. 45 The sixth factor was that the occurrence of known incidents when blood came into contact with Dr Vozzo's skin took place both while Dr Vozzo was in the employ of the appellants and when he was working for the respondent hospitals. This factor tends to be neutral. 46 There was evidence that supported each one of the factors specifically taken into account by the judge when coming to the conclusion that it was more probable that Dr Vozzo was infected by the HIV virus whilst in the employ of the appellants than while working for the other respondent hospitals. 47 In written submissions the appellants argued that his Honour took into account matters that were not relevant to his conclusion. Principally, the appellants challenged the relevance of the increased prevalence of the HIV virus, progressively, as from 1982 onwards, the fact that Dr Vozzo worked for the appellants for a longer period than the periods for which he worked for the hospital respondents, and the risk to Dr Vozzo of contracting the virus. 48 In my view, however, these matters were all relevant to the question of causation and his Honour was properly influenced by them. As a matter of logic, the greater the prevalence of the virus, the greater the risk of infection; the longer Dr Vozzo was employed by the appellants, the greater the prospect of him having been infected while in their employ (as long as there was a risk of infection – which there was). 49 In Seltsam Pty Ltd v McGuiness (2000) 49 NSWLR 262 Spigelman CJ (at 278) referred to some of the epidemiological evidence in that case which suggested "some increase in risk". The Chief Justice said that that evidence was relevant. He observed: "[c]ourts must determine the existence of a causal relationship on the balance of probabilities. However, as is the case with all circumstantial evidence, an inference as to the probabilities may be drawn from a number of pieces of particular evidence, each piece of which does not itself rise above the level of possibility. Epidemiological studies and expert opinions based on such studies are able to form 'strands in a cable' of a circumstantial case." His Honour observed that evidence of increased risk may be taken into account "for the purpose of drawing the inference that the particular exposure caused or materially contributed to the injury in the specific case". 50 The same point was made in E M Baldwin & Son Pty Ltd v Plane [1999] Aust Torts Reports 81-499 by Fitzgerald AJA who said (at 65,639): "All relevant circumstances, including an increase in the risk to the plaintiff from the defendant's breach of duty and the character and sequence of events, must be considered in deciding whether a defendant's breach of duty which is a possible cause of the plaintiff's damage probably materially contributed to that damage. Circumstances are relevant for this purpose if they assist in establishing or strengthening a causal connection between the defendant's breach of duty and the plaintiff's damage according to expert opinion or by the application of logic, common sense or experience." The present is not a case of breach of a duty, but the approach articulated by Fitzgerald AJA is of general application. 51 On this basis, the other factors to which Hughes CCJ had regard are relevant and were properly taken into account. These factors include what his Honour described as the "susceptibility of the population", and the fact that Dr Vozzo treated known HIV patients while he was employed with the appellants. 52 I now come to the specific grounds of appeal. 53 The first ground is that Hughes CCJ erred in law in directing himself that expert evidence supported his Honour's conclusion that Dr Vozzo had sustained injury in the employ of the appellants. As I understand it, this ground is directed to the evidence of Professor Carr. That evidence was relevant and supported Dr Vozzo's case in the respects to which I have already referred. Mr Poulos did not take up this ground in oral argument. I would not uphold this ground. 54 Ground 2 is that his Honour erred in law in finding that it was open to him to conclude that Dr Vozzo had sustained injury subsequent to 1989, when the only evidence was that injury occurred a minimum of five years prior to July 1994. This ground challenges the following statement by the judge: "Secondly, the professor said and Ms Techera submitted that, the manifestation of full blown AIDS was in 2000 and Professor Carr said that could only result or that would have resulted in an, and I emphasise again we are talking about probabilities here, eight to ten years before 2000 which would have made it 1990 to 1992." 55 I have recounted above the evidence that supports the proposition that Dr Vozzo may have been infected between 1989 and 1992. In my view, it was open to his Honour to conclude that Dr Vozzo could have been infected while he was in the employ of the appellants up to 1992. 56 Ground of appeal 3 is that his Honour erred in law in concluding that Dr Vozzo had proven causation on the balance of probabilities. This can only be an error of law on the view adopted in Ambulance Service of New South Wales v Daniel, namely, that it is a question of law whether the evidence is sufficient, in the sense that it is evidence which if fully accepted could properly base the finding of fact. As I have mentioned, I shall assume, without deciding, that this is the correct approach. 57 Mr Poulos rightly pointed out that there was no proof that any particular incident led to Dr Vozzo being infected. He submitted that, for that reason, the judge was not entitled to find that the infection had been caused while Dr Vozzo was employed by the appellants. I do not accept this submission. While it would have assisted Dr Vozzo to be able to prove that a particular incident that occurred while he was in the employ of the appellants caused the infection, proof of a particular incident is not essential to proof that an incident, resulting in infection, occurred while he was employed by the appellants. If the evidence showed that it was more likely than not that Dr Vozzo was infected at some time while he was in the employ of the appellants, that would be sufficient to establish causation. 58 Mr Poulos rightly submitted that there was no evidence that while Dr Vozzo was in the employ of the appellants, the blood of any infected person came into contact with his skin. Further, there were incidents that occurred while Dr Vozzo was in the employ of the respondent hospitals when blood came into contact with open wounds on Dr Vozzo's body. These matters however, while they are not without force, are by no means conclusive. 59 There was other evidence, to which I have already referred, that tended to support Dr Vozzo's case on causation. One aspect of Professor Carr's evidence that is of powerful probative value in regard to the question of proof of causation is his testimony that "50% of people who get infected [with the HIV virus] have a severe illness within ten years". On this basis, 50% of persons who (as was the case with Dr Vozzo) suffered a severe illness in 2000 were infected no later than 1990. It follows that well over 50% of persons who were infected in 2000 were infected after 1986. 60 I have pointed out that on Professor Carr's evidence, within a relatively short period prior to the eight to ten years from the diagnosis with the "severe illness", most sufferers from such an illness would have contracted the HIV virus. That is why there is little chance that Dr Vozzo was infected with HIV prior to 1984. I have also pointed out that the further inference is open that it is likely that Dr Vozzo was infected closer to the latter part of the 1980's rather than the earlier part. Professor Carr, as I have noted, did give other evidence that the infection would be closer to 1984 than 1989, but it was open to the judge to draw the inference to which I have referred. 61 These matters have to be taken together with the fact that, over the relevant period (1984 to 1992), Dr Vozzo worked for the appellants for twice as long he worked for the respondent hospitals, and the fact that, during that period, as found by the judge, the incidence of infection was progressively increasing. These matters constitute evidence on which the judge was entitled to find (as he did) that, as a matter of probabilities, Dr Vozzo was infected whilst in the employ of the appellants. 62 As Hodgson JA points out in his article "The Scales of Justice: Probability and Proof in Legal Fact finding" (1995) 69 ALJ 731 (at 738) bare numerical probability can be sufficient to establish proof on a balance of probabilities. This proposition is supported by Rose v Abbey Orchard Property Investments Pty Limited [1987] Aust Torts Reports 80-121 and Tenax Steamship Co Ltd v The Brimnes (Owners) [1975] QB 929. 63 In his article, his Honour observes at 739: "In both those cases [ Rose v Abbey Orchard Property Investments Pty Limited and Tenax Steamship Co Ltd ], it appears that the party bearing the onus had led all evidence reasonably available to that party, and that there was adequate material concerning the circumstances; and I suggest it is on that basis that the court in each of those cases was prepared to act on a bare numerical probability". In the present case Dr Vozzo led all evidence reasonably available to him and in my view there was adequate material concerning the relevant circumstances. 64 As Glass JA observed in Fernandez v Tubemakers of Australia Ltd [1975] 2 NSWLR 190 (at 197), the issue of causation involves a question of fact and a finding of causal connection may be open without any medical evidence at all to support it. Evidence will be sufficient if the materials offered "justify an inference of probable connection". 65 Mahoney JA in Fernandez (at 200) followed the approach of Herron CJ who said in EMI (Australia) Ltd v Bes [1970] 2 NSWR 238 (at 242): "Medical science may say in individual cases that there is no possible connection between the events and the death, in which case, of course, if the facts stand outside the area in which common experience can be the touchstone, then the judge cannot act as if there were a connection. But if medical science is prepared to say that it is a possible view, then, in my opinion, the judge after examining the lay evidence may decide that it is probable." 66 In the present case medical science does say that it is possible that Dr Vozzo was infected while in the employ of the appellants. Mr Poulos himself conceded that there was evidence that established that it was possible that Dr Vozzo was infected in the appellants' employ. There was lay evidence that went further and tended to support a finding of probable causation. In all the circumstances, it seems to me, it was open to the judge to find that causation had been established. 67 Mr Poulos submitted that the reasoning in Bendix Mintex Pty Ltd v Barnes (1997) 42 NSWLR 307 and Seltsam Pty Ltd v McGuiness was in conflict with any finding that causation was established on a balance of probabilities. 68 Bendix, as well as ICI Australia Operations Pty Ltd v Walsh (1997) 15 NSWCCR 279 (which was to like effect) were discussed in Wallaby Grip (BAE) Pty Limited (In Liq) v Macleay Area Health Service (1998) 17 NSWCCR 355. There Beazley JA (with whom Sheller JA and Sheppard AJA agreed) pointed out (at 362) that neither Bendix nor Walsh established any new principle. Rather, each case applied well-known principles of causation. 69 Both in Bendix and Walsh, the evidence went no further than establishing that the defendant's negligence could not be excluded as a cause of the injury. Here, as I have attempted to demonstrate, the evidence did go further and was sufficient to support a finding that causation had been proved on a balance of probabilities. In this way it differs from Bendix where Mason P pointed out (at 319) that: "The evidence does not establish the probability that it was any of the appellants (as distinct from the Royal Navy) whose negligence was the cause of [the plaintiff's] injuries. Indeed the evidence points firmly in the opposite direction." This of course was a finding of fact in an appeal by way of rehearing. It is not to be read as a statement about absence of evidence. 70 Similarly, in Seltsam the trial judge, as Davies AJA pointed out (at 305), treated the case essentially as if it turned on a contest between two epidemiologists who both testified as to possibilities. The evidence was simply not sufficient to establish causation on a balance of probabilities. 71 Accordingly, in my view neither Bendix nor Seltsam assists in the present case where the facts are fundamentally different. I would dismiss this ground. 72 Ground 4 is that his Honour erred in law in failing to direct himself that Dr Vozzo could not prove causation merely by establishing that injury in the employ of the appellants could not be excluded. This ground rests on the proposition that the facts in this case are on all fours with Bendix and Seltsam. That proposition cannot be accepted. The judge did not direct himself that causation could be established merely by the fact that injury in the employ of the appellants could not be excluded. His Honour, having assessed the evidence, determined, positively, that it was more probable on the facts that Dr Vozzo was injured in the employ of the appellants. This ground fails. 73 Ground 5 is that his Honour erred in law in concluding that it was more probable than not that Dr Vozzo had sustained injury in the employ of the appellants when the only evidence was that it was improbable. This ground, in essence, is no different to ground 3 and it is not necessary for me to deal with it separately. 74 The sixth ground is that his Honour erred in law in permitting his judgment on matters of probability to be influenced by matters of which there was no evidence, namely, of "the drug squad camped out [at Cabramatta]", and that "[Sutherland Shire] now at least is an area where the scourge of drug taking has necessarily grown". In my view, these remarks by the judge were only by way of side comments and were not matters that he took into account in coming to his judgment. 75 The seventh ground of appeal is that his Honour erred in law in purporting to conclude that because there was a risk of Dr Vozzo sustaining injury while in the employ of the appellants, he had sustained that injury. His Honour did not so conclude. The judge did take into account the risk of Dr Vozzo sustaining injury in the employ of the appellant, but merely as one of the relevant factors. As I have pointed out, that being a relevant factor, it was perfectly permissible for his Honour to have regard to it. 76 The last ground is that his Honour erred in failing to articulate the ground or grounds upon which his decision rested. 77 The judge expressly mentioned three matters that led him to determine that it was more likely than not that Dr Vozzo's infection occurred from 1986 to 1992 while he was in the appellants' employ. These were, firstly, the length of time that Dr Vozzo worked for the appellants in comparison with the time he worked for the respondent hospitals; secondly, the risk of injury he incurred while working for the appellants, thirdly, the means whereby, while working for the appellants, he might have been infected. In addition, the judge explained that he was taking into account the prevalence of the virus and specific aspects of Professor Carr's evidence. It is true that he did not expressly set out all of his reasoning that led him to make the value judgment that resulted in him considering that on the weight of the evidence causation had been proved. But, I think that the appellants could be under no misunderstanding as to why they lost. In my view the judge's reasons adequately set out the facts found and the reasoning applied. The judge's conclusion can be understood from the circumstances and from what was said: Belmont Night Patrol Pty Ltd v Woolworths Ltd [2004] NSWCA 235 at [29]. 78 In the circumstances I would dismiss the appeal with costs. 79 MASON P: I agree. 80 HANDLEY JA: I agree. 81 MASON P: The order of the Court will be appeal dismissed with costs. ********** Last Modified: 08/11/2004 DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. The onus remains on any person using material in the judgment or decision to ensure that the intended use of that material does not breach any such order or provision. Further enquiries may be directed to the Registry of the Court or Tribunal in which it was generated.