Opera Services Pty Ltd v Williams - [2023] NSWPICPD 25

DETERMINATION OF APPEAL AGAINST A DECISION OF THE COMMISSION CONSTITUTED BY A MEMBER
CITATION:	Opera Services Pty Ltd v Williams [2023] NSWPICPD 25
APPELLANT:	Opera Services Pty Ltd
RESPONDENT:	Christopher Williams
INSURER:	Hotel Employers Mutual Limited
FILE NUMBER:	A1-W1186/22
PRESIDENTIAL MEMBER:	Acting Deputy President Geoffrey Parker SC
DATE OF APPEAL DECISION:	4 May 2023
ORDERS MADE ON APPEAL:	1. The Certificate of Determination dated 19 May 2022 is confirmed.
CATCHWORDS:	WORKERS COMPENSATION – Consideration of expert evidence – Member applying judicial notice to reasoning process – section 43(2) of the Personal Injury Commission Act 2020 and rule 73 of the Personal Injury Commission Rules 2021
HEARING:	On the papers
REPRESENTATION:	Appellant:
Mr M van der Hout, solicitor
BBW Lawyers
Respondent:
Mr R Hanrahan, counsel
AJB Stevens Lawyers
DECISION UNDER APPEAL
MEMBER:	Mr P Sweeney
DATE OF Member’s DECISION:	19 May 2022

INTRODUCTION AND BACKGROUND

This is an appeal from the Certificate of Determination dated 19 May 2022.
The respondent, Christopher Williams, was employed by the appellant, Opera Services Pty Limited, as a cellar man at the Opera Bar, Lower Concourse, Bennelong Point, Sydney.
On 19 January 2016, he was transferring stock using a walk behind electric pallet jack. As he was doing so, he slipped and fell backwards landing heavily on his buttocks sustaining injury to the lower back.
The appellant accepted that the respondent had suffered injury to the cervical and lumbar spines but disputed that he had sustained a consequential medical condition of the digestive system.
In the Application to Resolve a Dispute, the respondent claimed lump sum compensation pursuant to s 66 of the Workers Compensation Act 1987 (the 1987 Act), alleging a whole person impairment (WPI) of 22%.
The Member found in favour of the respondent. He determined that as a result of the injury of 19 January 2016, Mr Williams suffered a consequential medical condition of his upper and lower digestive tracts. In the circumstances, the Member remitted the matter to the President for referral to a Medical Assessor to certify the degree, if any, of whole person impairment as a result of the injuries to the respondent’s cervical spine, lumbar spine and upper and lower digestive tract on 19 January 2016.
The appeal challenges the determination that the respondent sustained consequential gastrointestinal injuries.

STATEMENT OF REASONS AND FINDINGS

The Member received submissions on 9 May 2022 and delivered oral reasons for determination on 17 May 2022. The Certificate of Determination is dated 19 May 2022. (The references are to the oral reasons for determination. The pagination is by reference to the pagination in the transcript (T) of the oral reasons, which has been provided to both parties.)
The Member defined the task before him in the following terms:
“As this is only a claim pursuant to section 66, the role of the Commission is simply to find that there is or is not a consequential medical condition which results from a compensable injury. Whether a consequential medical condition is transitory or permanent, and whether it is affected by prior or subsequent medical conditions, and certainly whether it gives rise to permanent impairment are solely within the prerogative of a medical assessor. Similarly, it is not relevant that the consequential medical condition is not compensable pursuant to section 66, because of limitations in the SIRA guidelines for the evaluation of permanent impairment.”[1]
[1] T 5.12–23.
The Member found it unnecessary to recite the parties’ submissions in detail. He said the appellant submitted that the evidence did not establish either a consequential injury or a medical condition of the digestive tracts, or alternatively that a causal connection existed between the gastrointestinal condition and the spinal injury. The appellant submitted that Dr Greenberg, general and gastrointestinal surgeon qualified by the respondent, had “patently not considered”[2] the full range of risk factors giving rise to or potentially giving rise to the respondent’s lower and upper digestive tract problems, whereas Dr Sethi, gastroenterologist who it had qualified, had considered the entirety of the range of matters that might cause such problems.
[2] T 5.1.
The “salient points” of the evidence were recounted so that the parties could understand the manner in which the Commission had resolved their dispute.
The injury of 19 January 2016 occurred when the respondent was walking backwards. He slipped and fell, striking his lower back on the ground. In addition, his head struck the floor. The respondent ceased working for the appellant in March 2016 when he obtained a less physical position at the Cronulla RSL. The respondent resigned from that position after three months because of spinal pain. The respondent had not worked since that time. He continued to complain of widespread symptoms in his spine, with restriction of movement in the upper and lower limbs.[3]
[3] T 6.1–14.
The respondent first attended his GP on 12February 2016. He was referred to two neurosurgeons, Drs McKechnie and Reddy. He was referred to a pain specialist, Dr Gorman, and a psychologist. He consulted with Dr McKechnie for neurosurgical review on 28February 2017. An MRI demonstrated disc protrusions in the cervical spine and in the mid-thoracic spine. Dr McKechnie expressed the opinion that the respondent was unfit for work but that he was not a candidate for surgery.[4]
[4] T 6.15–25.
Dr McKechnie prescribed Lyrica and, following a negative reaction to that medication, he prescribed Endep. The Member concluded that in the years following his injury, “the evidence established that the [respondent] was prescribed multiple medications, some of which can be identified as NSAIDs”. NSAIDs are non-steroidal anti-inflammatory drugs.
On 13 November 2019, the respondent underwent a colonoscopy, followed by an endoscopy, both procedures were performed by Dr Wassim Rahman, a gastroenterologist. The summary of the procedures refers to the removal of two polyps. The histopathology report referred, however, to features of mild, chronic gastritis. Dr Rahman noted that the respondent thought that his gastrointestinal symptoms followed the ingestion of medication.[5]
[5] T 7.10.
The Member observed that the opinion of Dr Rahman “in part” supported the respondent’s belief.[6]
[6] T 7.13–15.
In October 2021 a gastroscopy was performed. The Member noted that this was reported as showing reflux oesophagitis, gastritis and duodenitis.
The Member said:
“There is no report from Dr Rahman in respect of that investigation so it is difficult to form any view as to whether the [respondent’s] condition has remained the same or deteriorated and it is also difficult to know what impact it has on the issue that I have to resolve.”[7]
[7] T 7.18–23.
The appellant’s case was “put through two medical practitioners”. First was the report of Dr Carney, a neurosurgeon, which the Member regarded as “only of background significance”.[8]
[8] T 7.26–27.
The Member noted that the appellant’s defence of the claim was largely, if not entirely, based on the opinion of Dr Sethi.[9]
[9] T 8.1–3.
Dr Sethi took a history that the respondent developed gastrointestinal symptoms following treatment for his orthopaedic injury. His reports set out a series of drugs that the respondent was either prescribed or purchased over the counter at the chemist shop. These included Meloxicam, Panadeine, Gabapentin and Nurofen.[10]
[10] T 8.10.
Dr Sethi said that the respondent had reflux disease with irritable bowel syndrome, “which had developed independently of the medications he had been prescribed for his work injury.”[11]
[11] T 8.12–14.
Dr Sethi identified two risk factors for the development of those conditions, namely the respondent’s weight (approximately 90kg). Dr Sethi said this was in the obese range. The other factor was smoking. These were likely to have caused the conditions in the respondent’s upper and lower digestive tracts. The respondent had regularly given a history of smoking, albeit the history given to Dr Sethi was that he smoked minimally. However the Member discounted this because, he said, “it is a notorious fact that people tend to underestimate their consumption of cigarettes.”[12]
[12] T 8.23.
Dr Sethi had considered the diagnoses of Dr Greenberg and stated that he did not agree with them. Dr Greenberg diagnosed reflux and dysmotility syndrome in the lower digestive tract. The Member did not find the difference between Dr Sethi and Dr Greenberg’s diagnoses with respect to the upper digestive tract as “obvious”. He accepted, however, that there was a difference.[13]
[13] T 8.33.
Dr Rahman, the respondent’s treating gastroenterologist, said the condition of diarrhoea was casually related to the ingestion of medication. Dr Sethi in a supplementary report said he disagreed with that opinion.
The respondent’s case was almost completely contained in the opinion of Dr Greenberg. Dr Greenberg expressed the opinion that the respondent had medication induced problems with both the upper and lower digestive tract. Dr Greenberg had a history of the drugs that the respondent had ingested since the injury and noted that of those, two, Nurofen and Naproxen, were in the class of drugs known as NSAIDs.
Dr Greenberg had stated that those drugs were “recognised to cause disturbances of the gastrointestinal tract … documented in the current version of MIMS.”[14] The Member said Dr Greenberg had set out in detail the potential effect of the medication.
[14] T 9.17–18.
Dr Greenberg’s ultimate diagnosis was reflux as opposed to the diagnosis of GORD (gastro-oesophageal reflux disease) by Dr Sethi and so far as the lower digestive tract was concerned, Dr Greenberg diagnosed irritable bowel syndrome. Dr Greenberg “causally” related both to the ingestion of medication.
The Member said:
“I have considerable doubt about the diagnosis reached by Dr Greenberg in respect of the lower digestive tract. Dr Rahman, as I indicated, diagnosed non-erosive reflux and diarrhoea in his report of 26 February of 2020. I think the evidence, taken as a whole, establishes that they are more likely to describe or characterise the condition than the terminology adopted by Dr Greenberg, however, terminology is probably unimportant in the ultimate resolution of the case.
Dr Rahman expressed the opinion, as I earlier indicated, that medication was probably the cause of diarrhoea, although it is not clear from his report that he thought that the medication was the cause of the mild erosive gastritis that he found on his examination. He noted, however, that the [respondent] had gained substantial weight following his work injuries and that this was: ‘the most significant risk factor for reflux disease’.”[15]
[15] T 9.25–10.7.
The Member noted that the comment by Dr Rahman that the increased weight was caused by the injury was an assumption that had not been proven by the evidence.[16]
[16] T 10.14.
The Member said this:
“Given the lay of the land, however, and the different medical opinions, I have reached the unusual conclusion that it is difficult to entirely discount or reject Dr Greenberg’s opinions on causation. As I indicated, he stated that the [respondent’s] gastritis, GORD, whatever one might wish to call it, was related to the use of NSAIDs and backed that up by referring to MIMS as supporting the contention. I have not gone to MIMS to read the relevant paragraph as I was not referred to it in argument. I have, however, heard evidence in many cases over the last decade or so, from gastroenterologists on both sides of the record, which leads to a view [that] the use of NSAIDs or the ingestion of that medication is a risk factor for gastritis. Obviously, what I had heard over the years is not determinative but it does lead me to the view that the report of Dr Greenberg on that issue is the more persuasive opinion.”[17]
[17] T 10.16–33.
The factors identified by Dr Sethi as relevant may have contributed to the onset of the respondent’s gastrointestinal problems. However, the Member said:
“the evidence establishes that those problems came on at a time when the [respondent] was using medications which were also a significant risk factor for gastritis.”[18]
[18] T 11.3–6.
The Member’s ultimate dispositive conclusion is summarised in the following passages:
“While it is easy to commit the logical fallacy of post ergo propter hoc, the sequence of events historically, in my opinion, is quite compelling. It leads to the conclusion that one should prefer Dr Greenberg’s opinion to that of Dr Sethi. It leads to the conclusion that [it] is likely that the [respondent’s] gastritis is, in part, related to the medication that he was ingesting at the time that he developed the symptomatology.
In those circumstances, I propose to accept that the [respondent] has gastritis and diarrhoea, both of which are causally related to the medication that he has ingested in 2016 and beyond. I prefer the opinion of Dr Greenberg on the issue of causation, although I do not accept all that he says about the characterisation or the diagnosis of the condition.
While it may not ultimately assist the [respondent’s] case, I propose to find that he did suffer a consequential medical condition of the upper and lower digestive tract, gastritis and diarrhoea. I propose, therefore, to remit the matter to the President for referral to a Medical Assessor to assess WPI in respect of the cervical and lumbar spines, and the consequential medical condition of both the upper and lower digestive tract.”[19]
[19] T 11.7–30.

CERTIFICATE OF DETERMINATION

The determination of the Commission was as follows:
“1.     Order the [respondent] to lodge under Cover of an Application to Admit Late Documents the gastroscopy report of Dr Rahman forwarded during the arbitration hearing.
2.      The [respondent] suffered injury to his cervical and lumbar spine arising out of and in the course of his employment on 19 January 2016.
3.      As a result of that injury the [respondent] suffered a consequential medical condition of his upper and lower digestive tract.
4.      Remit the matter to the President for referral to a Medical Assessor to certify the degree, if any, of whole person impairment as a result of injury to the [respondent’s] cervical spine, lumbar spine, and upper and lower digestive tract on 19 January 2016.
5.      Medical assessor to have access to the Application, the Reply, the Application to Admit Late Documents referred to in order 1 and the documents attached to each.”

GROUNDS OF APPEAL

The appellant challenges order 3 on two grounds, namely:
“Ground 1: The Member erred in applying ‘judicial notice’ to his reasoning process in respect of matters that were beyond those for which inferences could be drawn.
Ground 2: The Member erred in the reasoning process concerning the non-acceptance of Dr Sethi’s views in that he failed to comply with the principles of Wiki v Atlantis Relocations (NSW) Pty Limited.[20]”
[20] [2004] NSWCA 174 (Wiki).

ON THE PAPERS

The parties submit that the appeal can be dealt with “on the papers”.
Section 52(3) of the Personal Injury Commission Act 2020 (the 2020 Act) provides:
“(3) If the Commission is satisfied that sufficient information has been supplied to it in connection with proceedings, the Commission may exercise functions under this Act and enabling legislation without holding any conference or formal hearing.”
Procedural directions PIC2 and WC3 provide that I may be satisfied that the documents and submissions of the parties provide me with sufficient information so that the appeal can be determined on the papers without holding any formal hearing. I am so satisfied and intend to deal with the matter accordingly.

THRESHOLD MATTERS

The appeal has been commenced within 28 days of the Certificate of Determination dated 19May 2022.
The parties agree that the monetary threshold pursuant to s 352(3) of the Workplace Injury Management and Workers Compensation Act 1998 (the 1998 Act) is satisfied having regard to the amount claimed by the respondent for his whole person impairment (22% WPI $56,076.29).

INTERLOCUTORY DECISION: SECTION 352(3A) OF THE 1998 ACT

Section 352(3A) provides:
“There is no appeal under this section against an interlocutory decision except with the leave of the Commission. The Commission is not to grant leave unless of the opinion that determining the appeal is necessary or desirable for the proper and effective determination of the dispute.”
On 5 April 2023, I directed that the parties should provide written submissions as to whether the decision under appeal was interlocutory and whether in that event leave is sought to bring the appeal pursuant to s 352(3A) of the 1998 Act.
The appellant filed written submissions in which it noted that the Member’s determination relevantly included:
“2. The [respondent] suffered injury to his cervical and lumbar spine arising out of and in the course of his employment on 19 January 2016.
3. As a result of that injury the [respondent] suffered a consequential medical condition of his upper and lower digestive tract.”
The appellant makes the substantial submission:
“The Appellant submits that the above findings/orders are conclusive and bind the parties. Member Sween[e]y’s determination define[d] the rights and liabilities of each concerning liability for both injuries and the possible entitlement to compensation benefits provided by the Acts. As an (alternative) example, if Member Sween[e]y had (originally) determined in favour of the Appellant employer, the Respondent worker’s right from claiming compensation (permanent impairment or otherwise) for any condition to the upper and lower digestive tract would be prohibited. Overall, the decision has the effect of determining injury and thus fixing liability. The Appellant, in this Appeal, challenges findings made by the Member Sween[e]y with respect to injury.”[21]
[21] Appellant’s submissions dated 12 April 2023, [9].
The respondent in his submission on this point dated 19 April 2023 submits:
“the decision of Member Sweeney was final in the sense that it determined the issue of whether or not the digestive condition was a result of the pleaded injury”.[22]
[22] Respondent’s submissions dated 19 April 2023, [a].
The appellant’s submission should be accepted. The determination in order 3 which is challenged is a final determination, appeal from which does not require leave.
It is unnecessary to deal further with the parties’ submissions made on the basis that had I reached the conclusion that leave was required, why such leave should be granted having regard to s 352(3A).

NATURE OF THE APPEAL PURSUANT TO SECTION 352(5) OF THE 1998 ACT

The jurisdiction provided in s 352(5) of the 1998 Act is:
“An appeal under this section is limited to a determination of whether the decision appealed against was or was not affected by any error of fact, law or discretion, and to the correction of any such error. The appeal is not a review or new hearing.”
It is important to appreciate that the right of appeal requires the appellant to establish that the decision appealed against is affected by error. Sub-section 352(5) is not engaged merely because on appeal it is thought that a different outcome is preferable. Furthermore, the appeal is not a review.[23]

GROUND 1: THE MEMBER ERRED IN APPLYING “JUDICIAL NOTICE” TO HIS REASONING PROCESS IN RESPECT OF MATTERS THAT WERE BEYOND THOSE FOR WHICH INFERENCES COULD BE DRAWN

[23] See Northern NSW Local Health Network v Heggie [2013] NSWCA 255; 12 DDCR 95 per Sackville AJA; Raulston v Toll Pty Limited [2011] NSWWCCPD 25, [20].

Appellant’s submissions

The appellant submits that the Member was presented with two competing medical cases from different forensic experts (Dr Greenberg and Dr Sethi) relating to the disputed gastrointestinal conditions. The respondent failed to serve any opinion from his treating gastroenterologist (Dr Wassim Rahman) commenting on causation. As a consequence of this, the Member was required to perform an evaluative based fact-finding exercise, weighing the expert evidence and explaining why he preferred one case over another.

The Member’s statement, “I have, however, heard evidence in many cases over the last decade or so, from gastroenterologists on both sides of the record, which leads to a view that the use of NSAIDs or ingestion of that medication is a risk factor for gastritis”, is emphasised as indicating that he was not satisfied to a level of “actual persuasion” that the ingestion of medication materially contributed to the upper digestive tract condition.
It is acknowledged that the Member stated that his prior involvement in other cases and consequent understanding of the medical literature were not determinative, but the appellant submits nevertheless “it appears that this was the foremost reason for his preference of Dr Greenberg’s opinion; and ergo the acceptance of the fact in issue.”[24]
[24] Appellant’s submissions, [11].
The appellant refers to the decision of the Court of Appeal in Strinic v Singh[25] where Beazley JA at [60] said the fundamental judicial obligation was to make findings of fact on proved evidence (not being matters of common knowledge or judicial knowledge). The fact of the judge’s experience in adjudicating medical cases does not replace the requirement for findings based on the evidence. Familiarity with the material does not make the judge an expert in the case.
[25] [2009] NSWCA 15 (Strinic).
The appellant submits that there are two exceptions to the principles set forth in Strinic relevant to the Personal Injury Commission, namely:
(a) the Commission is not bound by the rules of evidence but may inform itself of any matter in such manner as it thinks appropriate.[26] However, the Commission must comply with the rules of procedural fairness in r 73 of the Personal Injury Commission Rules 2021 (the 2021 Rules), and
(b) “as a specialist tribunal, the Commission’s Members (like Judges of the Compensation Court before it) have experience enabling them to draw inferences from facts which an ordinary tribunal may not and are entitled to rely upon general knowledge acquired in that capacity in certain circumstances.”[27]
[26] Section 354(2) of the 1998 Act.
[27] Appellant’s submissions, [17], citing MMI Workers Compensation (NSW) Ltd v Kennedy [1993] NSWCC 26; 9 NSWCCR 482; ICI Australia Operations Pty Ltd v WorkCover Authority of New South Wales [2004] NSWCA 55.
The Member’s reference to not having read the relevant paragraph in MIMS meant that “the basis of his reasoning was an unsubstantiated assumption and an unqualified opinion”.[28]
[28] Appellant’s submissions, [16].
The appellant submits it was not open to the Member to accept the respondent’s medical case “because of his own experience and involvement in other matters. The Appellant has no outward knowledge of which certain cases [led] to the knowledge acquired by the learned Member. His approach involved a breach of the rules of procedural fairness and, though he gave one other brief reason for accepting the Respondent’s medical case, one cannot be satisfied that his error made ‘no possible difference to the result’”.[29]
[29] Appellant’s submissions, [20] citing Stead v State Government Insurance Commission [1986] HCA 54; 164 CLR 141, 146.
The appellant’s submission is that the Member “effectively decided the case on evidence which he conceded was never argued by the Respondent’s representatives during the Arbitration hearing and without giving the Appellant the opportunity to be heard”.[30]
[30] Appellant’s submissions, [19].

Respondent’s submissions

The respondent submits that the Member referred to the salient points extracted from the doctors’ reports and clinical notes that enabled him to legitimately infer matters that were ultimately persuasive as follows:
(a)    The respondent informed Dr Rahman that he thought his gastrointestinal symptoms followed the ingestion of medication. The Member accurately recorded that Dr Rahman opined that “medication was probably the cause of diarrhoea”.[31]
(b)    Dr Rahman reported on 2 June 2020 that “Christopher states that his diarrhoea started after using multiple analgesics including non-steroidal anti-inflammatory drugs (NSAID) for his various joint pains. This is the most likely cause and no other abnormalities have been identified on his investigations.”[32] (emphasis in the original submission).
(c)    Dr Rahman had taken a history of the other relevant potential causal factors as suggested by Dr Sethi, namely moderate abdominal obesity and smoking 8 cigarettes per day.
(d)    Dr Rahman noted the worker had gained substantial weight following his work related injuries. Evidence of this fact in the report is admissible for all purposes even though not referred to in the worker’s statement and is sufficient to found a factual finding. Moreover the doctor expresses the view that “this is his most significant risk factor.”[33]
[31] T 10.1.
[32] Respondent’s submissions, [1(a)(i)].
[33] ARD, p 480.
The respondent submits that:
“It can therefore be seen that the worker’s increased weight as well as his NSAID consumption persuaded the Member that one or both [of] those factors played a material part in the occurrence of the worker’s digestive symptoms, particularly in the context of the worker not being able in the course of his earlier treatment to tolerate a variety of medications over several years”.[34]
[34] Respondent’s submissions, [1(b)].
The Member performed a nuanced evaluative normative fact finding exercise and made clear that his experience from previous cases was not determinative. It was nevertheless “of undoubted assistance in helping him understand the evidence”.[35] His previous knowledge led him to take an informed position concerning the relative persuasiveness of the evidence as it stood including the diametrically opposed expert medical opinions. The respondent cites Adelaide Stevedoring Co Ltd v Forst[36] for the proposition that the Member “proceeded by a course of reasoning which combined common sense with the application of logic to physiological facts.”
[35] Citing Strinic.
[36] [1940] HCA 45; 64 CLR 538, per Rich ACJ.

Appellant’s submissions in reply

The appellant submits that the respondent has not completely recognised and addressed what the particular ground of appeal seeks to achieve, namely, that it was not open to the Member to accept the respondent’s medical case on the basis of his own experience and involvement in other matters. The appellant makes further reference to the decision of Strinic and submits that the respondent has failed to address the fact that the Member took an informed position not on the foundation of the evidence, but rather on an unsubstantiated assumption and unqualified opinion.
The Member did not adequately weigh the expert evidence or explain why one view was necessarily preferred over the other. Instead, his own experience was introduced. The process to arrive at the ultimate conclusion was affected by error and if that is wrong, the respondent has not demonstrated why this is so.
The appellant reiterates the proposition that there was no report from Dr Rahman commenting on the worker’s condition and any relationship to employment.
The appellant submits that the respondent did not argue before the Member at first instance that the alleged weight gain following the injury was a factor which played a material part in the occurrence of his gastrointestinal issues. The appellant submits that that submission should be disregarded.

Consideration

It is appropriate to note that the Commission is not bound by the strict rules of evidence but may inform itself on any matter in the manner the Commission thinks appropriate and as the proper consideration of the matter permits.[37]
[37] Section 43(2) of the 2020 Act.
However, r 73 of the 2021 Rules applies. The Member is to have regard to four principles:
(a)    evidence should be logical and probative;
(b)    evidence should be relevant to the facts in issue and the issues in dispute;
(c)    evidence based on speculation and unsubstantiated assumptions is unacceptable, and
(d)    unqualified opinions are unacceptable.
The brevity of the Member’s reasoning, which does not descend to a detailed analysis of the reports of either Dr Greenberg or Dr Sethi, makes tenuous a conclusion that s 43(2) and r 73 have been satisfied. Notwithstanding, for the reasons that follow I do not accept that the Member’s preference for the evidence of Dr Greenberg was in error, and Ground One of the appeal is rejected.
The Member’s reasons for preferring the respondent’s case may be summarised as follows:
(a)    Dr Greenberg’s opinion on causation that the respondent’s gastritis or GORD was related to the use of NSAIDs was supported by entries in MIMS.[38]
(b)    The evidence established that the respondent’s gastrointestinal problems “came on at a time when the [respondent] was using medications which were also a significant risk factor for gastritis.” The sequence of events historically was “quite compelling”.[39]
(c)    The Member said that his own experience with previous cases that he had heard was “not determinative” but did assist in being persuaded by Dr Greenberg.[40]
(d)    Dr Rahman’s opinion that post-injury weight gain was “the most significant risk factor for reflux disease”, which the Member thought was of “theoretical importance”, had not been proven by the evidence.[41]
[38] T 10.20.
[39] T 11.3–9.
[40] T 10.30.
[41] T 10.5–14.
It is necessary to consider Dr Greenberg’s report of 9 February 2021 in more detail than may otherwise have been the case had the Member’s reasons being more extensive.
Dr Greenberg said:
“Nurofen and Naproxen are a class of drugs known as non-steroidal anti-inflammatory or NSAIDs. In particular, NSAIDs are recognised to cause disturbance to the gastrointestinal tract and documented in the current version of MIMMS (2014).
NSAIDs are also recognised to cause significant GI side effects particularly affecting the upper GI tract. It is accepted that on occasions the effects on the stomach can be serious and on occasions cause serious GI bleeding.
The most common adverse reaction occurring with Nurofen Plus is gastrointestinal.
…
· Gastritis
…
· Diarrhoea
…
Nurofen Plus is a combination of Ibuprofen and 200mg Codeine Phosphate 12.8mg. Nurofen Plus is used for mild to moderate pain. Codeine is recognised to be associated with a number of GI side effects.
…
Panadeine Forte is known to cause a disturbance of gastrointestinal motility and as [a] consequence resulting in delay of gastric emptying. This would almost certainly aggravate any existing gastroesophageal reflux and aggravate the symptoms.
…
Mr Williams has no previous history of any gastrointestinal problems.”[42]
[42] ARD, pp 436–437.
Dr Greenberg supported the respondent’s case by reference to the following:
(a)    the scientific material contained in the MIMS confirming side effects from the consumption of NSAIDs;
(b)    the correspondence between the “documented” side effects of the medications, and
(c)    the absence of a previous history of gastrointestinal problems.
It is important to note that no objection was taken by the appellant at the hearing before the Member of the reference to MIMS by Dr Greenberg. I do not accept the appellant’s submission[43] that the Member not having read the relevant paragraph in MIMS meant that the “basis of his reasoning was an unsubstantiated assumption and an unqualified opinion”.
[43] Appellant’s submissions, [16].
The statement that NSAIDs were recognised to cause disturbance to the gastrointestinal tract was derived from Dr Greenberg’s report and was Dr Greenberg’s paraphrase of the entry in MIMS. Dr Greenberg’s paraphrasing of the entry in MIMS was not objected to or the subject of qualification or contradiction by evidence from Dr Sethi or otherwise. It was available for the Member to act on for all purposes. It follows the Member had not merely the opinion evidence of Dr Greenberg but also evidence in the form of the MIMS entry. The latter was evidence which could not seriously be disputed.
The respondent is correct to point out that Dr Rahman’s evidence in the report dated 2June 2020 was that the respondent’s diarrhoea started after the worker commenced using multiple analgesics including NSAIDs. He corroborated the assumption that the diarrhoea was “most likely” caused by the injury.
Dr Sethi concedes in his report of 5 July 2021:
“The analgesic medications that Mr Williams was prescribed can potentially cause constipation but do not usually cause diarrhoea.”[44]
[44] Reply, p 22.
The Member said that his experience with previous cases was not “determinative”.
I am not persuaded that the Member used his knowledge from other cases to do more than enable him to understand the evidence of the medical referees. Although the brevity of the Member’s reasoning is to be regretted, I am not persuaded that there is evidence of error.
It seems to me that the Member was entitled to accept that the entry in MIMS relied upon by Dr Greenberg was objective support from a source which could not reasonably be challenged in support of the respondent’s case. In the circumstances, I am not persuaded that the Member was in error and reject Ground 1 of the appeal.

GROUND 2: THE MEMBER ERRED IN THE REASONING PROCESS CONCERNING THE NON-ACCEPTANCE OF DR SETHI’S VIEWS IN THAT HE FAILED TO COMPLY WITH THE PRINCIPLES OF WIKI

Appellant’s submissions

The appellant submits that the principle established in Wiki at [62] was that in order to reject a coherent and reasoned opinion expressed by a suitably qualified expert, it should be the subject of a coherent and reasoned rebuttal, unless it can be discounted for other reasons. The appellant’s submission is that Dr Sethi provided a coherent and reasoned opinion as to causation concerning the gastrointestinal conditions which Dr Greenberg did not. There was no evidence produced from the respondent’s treating gastrointestinal surgeon commenting on causation.
Dr Sethi’s opinion should have been preferred because he examined the clinical notes from the treating gastroenterologist. Dr Greenberg was never furnished with the clinical file from Dr Rahman, nor was he requested to comment in reply on the reports and alternative opinion of Dr Sethi. It is submitted that before Dr Greenberg could be preferred, he needed to have considered all the alternatives and explained why he preferred his own conclusions regarding causation.
The appellant sets out the description of the “post hoc fallacy” from Nguyen v Cosmopolitan Homes (NSW) Pty Ltd.[45] There are two passages, but that of most significance and emphasised by the appellant is as follows:
“Where B (not having occurred before) closely follows A, and where there is expert evidence to suggest that an event of the nature of A may cause a result of the nature of B, then the inference of causation may be drawn if, on the evidence, there is no acceptable alternative cause available. … I would add that the same inference may be available if ordinary human experience, rather than expert evidence, suggests that ‘A’ events have been known to cause ‘B’ results, and if there is no evidence of any other acceptable cause.”[46]
[45] [2008] NSWCA 246 (Nguyen).
[46] Nguyen, [63].
The appellant submits that in the present matter:
“… the difficulty with the learned Member’s approach is that he failed to properly consider the contrary opinion expressed by the Appellant’s expert. Rather than engaging with the competing views, and properly analysing them, to determine which was to be preferred and why, he committed the logical ‘post hoc propter hoc’ error. In these circumstances the process of fact finding has miscarried.
The mere inference that any gastrointestinal condition occurred as a result of the work-related condition, simply because the Respondent was ingesting medication at a time his symptoms manifested, was not open to the learned Member in the presence of alternative causes identified by Dr Sethi. Although he understood the alternative ‘risk factors’, the learned Member did not provide a coherent rebuttal against Dr Sethi’s well-reasoned opinion.”[47]
[47] Appellant’s submissions, [29]–[30].

Respondent’s submissions

The respondent submits:
“The principle cited [i.e. from Wiki] is intended to ‘enable the losing party to understand properly the grounds upon which the case was lost’. It is clear that even so, in the present case the Member found that when all the circumstances were considered and weighed up it was the temporal connection that was overall ‘quite compelling’.”[48]
[48] Respondent’s submissions, [2(b)].
In Wiki the error was the “preference for medical evidence from a practitioner merely because of his reputation. A decision based solely on demeanour will not always provide the losing party with a satisfactory explanation. The Court confirmed that what is required is a rational examination and factual analysis within a reasoned framework.”[49]
[49] Respondent’s submissions, [2(c)].
Here the Member pointed to a sequence of events historically. He recognised that on a common sense basis the view expressed by Dr Greenberg, that the medication consumed contributed, at least in part, and in a material way to the symptoms experienced by the worker, should be accepted.
Dr Sethi’s opinion that the medications consumed by the worker played no part at all in the aetiology of the worker’s gastric symptoms is difficult to accept. In this case there are multiple factors all capable of (separately or together) playing a part in the genesis of and the maintenance of the condition in the worker.
The respondent makes the point:
“The Member did not deny that the factors that Dr Sethi relied upon in the formation [of] his opinion were relevant, and that they may also have contributed to the onset or maintenance of the worker’s gastrointestinal problems, he simply distilled with them the obvious additional factor, namely the consumption of medication, to conclude that multiple factors, including the medication ‘in part’ were factors leading to and causative of the worker’s gastric condition.”[50]
[50] Respondent’s submissions, [2(f)].
The Member’s conclusion was fortified by “notorious scientific facts of which he is able to take judicial notice both by reason of his experience and by reference to accepted scientific material (MIMS) that the drugs consumed by the worker namely Nurofen and Naproxen were NSAIDs of a type well known to contribute to gastrointestinal disturbance.”[51]
[51] Respondent’s submissions, [2(g)].
The respondent concludes:
“It is not that it was ‘never argued’, as submitted by the appellant, rather it is not arguable, as a notorious scientific fact that even the layman would be aware of from common experience (likely having been told by a medical practitioner not to consume drugs on an empty stomach) that certain medications are indeed capable of causing gastric problems.”[52]
[52] Respondent’s submissions, [2(h)].

Appellant’s submissions in reply

In reply, the appellant refers to Kooragang Cement Pty Ltd v Bates[53] to the effect that certain events occurring which “predisposed the worker” to subsequent injury would not of itself be sufficient to establish that such incapacity or death results form a work injury. The appellant quotes then from March v Stramare (E & MH) Pty Ltd[54] to the effect that “the educative effect of the expert evidence makes an appeal to common sense notions of causation largely meaningless or produces findings concerning causation which would often not be made by an ordinary person uninstructed by the expert evidence.”
[53] (1994) 35 NSWLR 452, 463–464.
[54] [1991] HCA 12, [19] per McHugh JA.
The appellant submits that the supposed notorious scientific fact that ingesting medication is capable of causing gastrointestinal issues “lacks any substance and probative value”. It is asserted that one cannot favour speculative arguments of common knowledge or notorious scientific fact over expert medical opinion. To do so would undermine the necessity for expert opinion in establishing causation and would lead to gross error of law.

Consideration

In my view, the respondent’s argument is correct.
The Member was supported by Dr Greenberg’s opinion and recitation of the support from MIMS. That was objective and scientific evidence not rebutted and, in my view, to some extent is supported by Dr Sethi.
Dr Greenberg relied on the entries in MIMS which presumably accorded with his clinical experience to offer his opinion of the likely effect of Nurofen and Naproxen on the worker. This was a conventional application of established scientific data to the circumstances of Mr Williams’ medical condition. This was neither speculative nor unscientific. The Member was entitled to act on Dr Greenberg’s opinion.
The Member was not required to give elaborate reasons rebutting Dr Sethi’s opinion. An alternative hypothesis to Dr Sethi’s opinion was provided by the scientific content of the MIMS; the opinion of Dr Greenberg and to a degree by Dr Rahman’s partial agreement with the respondent’s assumption.
Furthermore, the Member was not required to discount his acceptance of Dr Greenberg’s reliance on MIMS by reason of Dr Sethi’s reports because those reports made no rebuttal of that aspect of Dr Greenberg’s report.
In my view, the Member is not shown to be in error in the manner in which he dealt with Dr Sethi’s material. It was inevitable, given that he preferred Dr Greenberg’s material, supported as it was by the MIMS entry, that Dr Sethi’s report would be rejected. He was not required to give an elaborate explanation as to why that was so.
This was not a matter in which the Member determined to prefer Dr Greenberg because of demeanour or Dr Greenberg’s eminence over Dr Sethi. He preferred Dr Greenberg because of the support for Dr Greenberg’s hypothesis contained in the MIMS and the correlation between the respondent’s consumption of NSAIDs and the development of gastrointestinal symptoms.
There was no other acceptable alternative cause available because Dr Sethi in his hypotheses failed to address the MIMS entry. The objective scientific material in the MIMS entry, together with the temporal correlation, was sufficient to persuade the Member that Dr Greenberg’s report and hypothesis should be preferred.
No error is demonstrated in that conclusion on his part. Ground 2 of the appeal is rejected.

CONCLUSION

In my view it was open to the Member to make the determination that he did. The appellant has failed to demonstrate error so as to engage the jurisdiction provided for in s 352(5) of the 1998 Act. The appeal is rejected.

DECISION

The Certificate of Determination dated 19 May 2022 is confirmed.

Geoffrey Parker SC
Acting Deputy President

4 May 2023