Wuth v Comcare

The legislation 10 Before setting out the factual background to the proceeding in more detail, I will identify some relevant provisions of the SRC Act, as they form the framework around which the factual issues must be understood. The date of 12 February 2007 on which the applicant claimed she first noticed an injury is material to the determination of what version of the applicable provisions of the SRC Act are applicable to her claim. The following summary is based upon the compilation of the SRC Act prepared on 1 July 2006, prior to the commencement on 13 April 2007 of amendments effected by the Safety, Rehabilitation and Compensation and Other Legislation Amendment Act 2007 (Cth), which included substituted definitions of "injury" and "disease" which are not relevant to this appeal, because the applicable terms are those in the SRC Act prior to the 2007 amendments. All references to the SRC Act in these reasons are based upon that 2006 compilation. 11 Section 14 of the SRC Act is the central provision that provides for Comcare's liability to pay compensation in accordance with the Act in respect of an injury - 14 Compensation for injuries (1) Subject to this Part, Comcare is liable to pay compensation in accordance with this Act in respect of an injury suffered by an employee if the injury results in death, incapacity for work, or impairment. (2) Compensation is not payable in respect of an injury that is intentionally self-inflicted. (3) Compensation is not payable in respect of an injury that is caused by the serious and wilful misconduct of the employee but is not intentionally self-inflicted, unless the injury results in death, or serious and permanent impairment. 12 A key concept for the purposes of the liability under s 14 and other provisions of the SRC Act is "injury". Section 4(1) of the Act defined "injury" as follows - injury means: (a) a disease suffered by an employee; or (b) an injury (other than a disease) suffered by an employee, being a physical or mental injury arising out of, or in the course of, the employee's employment; or (c) an aggravation of a physical or mental injury (other than a disease) suffered by an employee (whether or not that injury arose out of, or in the course of, the employee's employment), being an aggravation that arose out of, or in the course of, that employment; but does not include any such disease, injury or aggravation suffered by an employee as a result of reasonable disciplinary action taken against the employee or failure by the employee to obtain a promotion, transfer or benefit in connection with his or her employment. 13 In turn, "disease" was defined in s 4(1) of the Act as follows - disease means: (a) any ailment suffered by an employee; or (b) the aggravation of any such ailment; being an ailment or an aggravation that was contributed to in a material degree by the employee's employment by the Commonwealth or a licensed corporation. 14 At the next level, "ailment" was defined as follows - ailment means any physical or mental ailment, disorder, defect or morbid condition (whether of sudden onset or gradual development). 15 Section 19 of the SRC Act provides for the payment, in respect of an injury, of weekly payments during a period of incapacity. Section 19 has a number of sub-sections, of which I will set out only s 19(1) and (2) - 19 Compensation for injuries resulting in incapacity (1) This section applies to an employee who is incapacitated for work as a result of an injury, other than an employee to whom section 20, 21, 21A or 22 applies. (2) Subject to this Part, Comcare is liable to pay to the employee in respect of the injury, for each week that is a maximum rate compensation week during which the employee is incapacitated, an amount of compensation worked out using the formula: NWE - AE where: AE is the greater of the following amounts: (a) the amount per week (if any) that the employee is able to earn in suitable employment; (b) the amount per week (if any) that the employee earns from any employment (including self-employment) that is undertaken by the employee during that week. NWE is the amount of the employee's normal weekly earnings. 16 The ascertainment of an employee's normal weekly earnings, or NWE, is necessary for the purposes of the calculation of weekly payments, and it was the subject-matter of the determination by the Tribunal that is the subject of this appeal. The calculation of normal weekly earnings is undertaken in accordance with the detailed provisions of s 8. For present purposes, it is necessary to set out only s 8(1) and (5) - 8 Normal weekly earnings (1) For the purposes of this Act, the normal weekly earnings of an employee (other than an employee referred to in subsection (2)) before an injury shall be calculated in relation to the relevant period under the formula: (NH x RP) + A where: NH is the average number of hours worked in each week by the employee in his or her employment during the relevant period; RP is the employee's average hourly ordinary time rate of pay during that period; and A is the average amount of any allowance payable to the employee in each week in respect of his or her employment during the relevant period, other than an allowance payable in respect of special expenses incurred, or likely to be incurred, by the employee in respect of that employment. … (5) Where, because of the shortness of the relevant period, the normal weekly earnings as calculated in relation to the relevant period under subsection (1) or (2) would not fairly represent the weekly rate at which the employee was being paid in respect of his or her employment before the injury, the normal weekly earnings before the date of the injury shall be calculated in relation to such other period as Comcare considers reasonable for the purpose of arriving at an amount that does fairly represent the weekly rate at which the employee was being so paid. 17 Sub-sections 8(1) and (5) set out above refer to the "relevant period". Subject to some qualifications, s 9 provides that the "relevant period" is the period of two weeks before the date of injury - 9 Relevant period (1) For the purposes of calculating the normal weekly earnings of an employee before an injury, a reference in section 8 to the relevant period is, subject to this section, a reference to the latest period of 2 weeks before the date of the injury during which the employee was continuously employed by the Commonwealth or a licensed corporation. 18 If an employee who is incapacitated for work as a result of an injury retires, either voluntarily or by compulsion, then under ss 20, 21 and 21A of the SRC Act any entitlement to weekly compensation is calculated differently, and takes account of any pension and lump sum benefits received by the employee under a superannuation scheme. 19 Amongst other compensation that is payable under the SRC Act in the event of an injury, are lump sum benefits payable under s 24 and s 27 in the event of permanent impairment. The entitlement to lump sum benefits is determined by reference to the degree of permanent impairment as assessed in accordance with the "Guide to the Assessment of the Degree of Permanent Impairment" prepared by Comcare and approved by the Minister under s 28 of the Act. 20 Part VI of the SRC Act is titled "Reconsideration and review of determinations". For the purposes of that Part a "determination" is defined by s 60(1) as meaning a determination, decision or requirement made under a range of provisions which, relevant to this appeal include ss 8, 14, 19, and 20. 21 Section 62 provides that a "determining authority" may reconsider a determination - 62 Reconsideration of determinations (1) A determining authority may, on its own motion: (a) reconsider a determination made by it; (b) cause such a determination to be reconsidered by a person to whom its power under this section is delegated, being a person other than the person who made, or was involved in the making of, the determination; whether or not a proceeding has been instituted or completed under this Part in respect of a reviewable decision made in relation to that determination. (2) A request to a determining authority to reconsider a determination made by it may be made by: (a) the claimant; or (b) if the determination affects the Commonwealth - the Commonwealth; or (c) if the determination affects a Commonwealth authority - that Commonwealth authority. … (5) Where a person reconsiders a determination, the person may make a decision affirming or revoking the determination or varying the determination in such manner as the person thinks fit. 22 Sub-section 60(1) defines "determining authority" in relation to a determination as the person who made the determination. 23 Section 64 provides for application to be made to the Tribunal for review of a "reviewable decision", which is defined by s 60(1) as including a decision made under s 62.

Background 24 The applicant was employed by the Commonwealth for a number of years. In December 2005, when the applicant worked in Canberra at the Department of Health and Ageing, she contracted a viral condition, referred to as Epstein-Barr virus, which resulted in migraine headaches. This condition was not alleged to be work-related. 25 On 14 November 2006, the applicant accepted an offer of permanent re-assignment from the Department of Health and Ageing to the Department of Finance and Administration (as it was then known) with effect from 27 November 2006. The offer of re-assignment stated that the applicant's employment would be part-time at 29.4 hours per week. A payroll check list that was in evidence noted that the applicant would be working Monday, Tuesday, Thursday and Friday. 26 The applicant and the Secretary of the Department of Finance and Administration entered into an Australian Workplace Agreement under the Workplace Relations Act 1996 (Cth). The applicant executed the Agreement on 31 May 2007, and a delegate or agent of the Secretary executed the Agreement on 18 June 2007. As to the applicant's hours of work, the Agreement provided - 2.3 Hours of work You are required to work ordinary hours and such reasonable additional hours as are necessary for the performance of your duties. Your ordinary hours are 36 hours and 45 minutes per week or 7 hours and 21 minutes per day, subject to any part-time arrangements agreed between you and your Manager. If you work part-time your remuneration (salary and any performance bonus) and leave entitlements will be calculated on a pro rata basis, based on the full-time ordinary hours. Your remuneration includes payment for all hours worked, including reasonable additional hours. The relevant period for the purposes of calculating the average hours you work shall be 12 months. Time Off In Lieu (TOIL) may be granted by your Manager in consultation with the General Manager to recognise short term additional hours worked. Supplementary leave may be determined by the Remuneration Committee to recognise additional hours spent on specific, approved projects. 27 At the time of the applicant's transfer to the Department of Finance and Administration in November 2006, she was no longer experiencing headaches. However, subsequently the applicant was required to work more hours than those that had been specified, and between early 2007 and May 2007 she developed migraine headaches when she was working long hours and was fatigued. The applicant has not worked since May 2008 as a consequence of a debilitating condition from which she claims to suffer, which involves chronic daily headaches. 28 On 27 May 2010, the applicant's employment by the Commonwealth was terminated on the grounds of invalidity. Following her retirement, the applicant was in receipt of a superannuation pension. 29 The dispute that is the subject of the current appeal has its genesis in a decision by Comcare in August 2013 that the applicant's normal weekly earnings were to be calculated under s 8 of the SRC Act on the basis of 29.4 hours, and not the longer hours that the applicant was working at the time of the onset of her condition. Disputes relating to this issue have been the subject of a review by the Tribunal, an earlier appeal and cross-appeal to this court that was determined at first instance by Rares J, an appeal by Comcare from the decision of Rares J to the Full Court, a further determination by Comcare, and a further review by the Tribunal that is the subject of this appeal. Intertwined with the disputation about the applicant's normal weekly earnings was a claim by the applicant for lump sum payments under ss 24 and 27 of the SRC Act on the ground of permanent impairment. Those claims were also determined adversely to the applicant by the Tribunal's decision of 3 September 2020, but are not the subject of appeal. However, it will be necessary to refer to the issues arising on those claims as part of the context to this appeal. 30 Going back, on 29 April 2010 the applicant made a claim for statutory compensation, claiming that she suffered from "entrenched chronic daily headache (intractable migraine) arising from an exacerbation of post-viral fatigue". The applicant claimed that she had a "constant migraine quality headache with accompanying nausea, vertigo photophobia and phonophobia", and that she suffered an "exacerbation of fatigue symptoms with inability to undertake normal daily activities". In the claim form the applicant stated that she was first injured, or first noticed that she was ill, on 12 February 2007, and that she first sought medical treatment for her injury on that day. In an annexure to her claim form, the applicant detailed the circumstances and treatment of her condition, and supported her claim with references to diagnoses by treating medical practitioners, including specialists. Her treatment included several admissions to hospital as an inpatient. In a report dated 14 September 2009, the applicant's treating neurologist, A/Prof Raymond Garrick, identified a prominent inflammatory illness that the applicant suffered in December 2005, and gave the opinion that the applicant's headaches originated from an inflammatory process, but were now based on persisting disordered neurotransmission. Identifiable stressors contributing to the persistence of symptoms were said to include prolonged work times, the anxiety of work expectations, and the probability of postural factors. In short summary, the compensable circumstances were claimed to include aggravation of the applicant's condition by a requirement that the applicant work hours significantly in excess of those that had been recommended and agreed having regard to her condition and diagnosis. 31 On 24 August 2010, Comcare rejected the applicant's claim that she had suffered injury. Comcare's written reasons for rejection included references to the definition of "disease" in s 5B of the SRC Act, and a requirement that employment contribute to a "significant" degree, and not merely to a "material" degree as the definition of "disease" in s 4(1) of the Act prior to the amendments had provided. Section 5B was inserted by the Safety, Rehabilitation and Compensation and Other Legislation Amendment Act 2007 (Cth), to which I referred earlier, and commenced operation on 13 April 2007, which was after the applicant's claimed date of injury. The transitional provisions in item 41 of Schedule 1 of the amending Act provided that the amended definition of disease applied to an ailment or an aggravation of an ailment that an employee suffered on or after the day after which the amending Act received Royal Assent, which occurred on 12 April 2007. The time at which an employee suffers an ailment or aggravation is determined under s 7(4) of the SRC Act and, relevantly, is the earlier of the date on which the employee first seeks medical treatment for the disease or aggravation, or the date on which the disease or aggravation first resulted in incapacity for work. As I referred to above, in her claim form the applicant stated that she first sought medical treatment on 12 February 2007. Comcare's rejection of the applicant's claim was affirmed upon reconsideration of the claim on 29 July 2011. 32 On 30 September 2011, the applicant applied to the Tribunal for review of Comcare's rejection of her claim of compensable injury. 33 On 14 September 2012, and following an alternative dispute resolution process, pursuant to s 34D(2) of the Administrative Appeals Tribunal Act the Tribunal set aside Comcare's decision of 29 July 2011, and in substitution decided that - 1.1. the Applicant suffered Chronic Daily Headache being a disease that was significantly contributed to by the Applicant's employment with the Department of Finance and Deregulation (Agency) with a deemed date of injury of 27 February 2007; 1.2. the Respondent is liable to pay compensation to the Applicant, pursuant to section 14 of the Safety, Rehabilitation and Compensation Act 1988 (Cth) (SRC Act) in respect of Chronic Daily Headache; and 1.3. the Respondent is not liable under section 14 of the SRC Act to pay compensation to the Applicant in respect of post-viral fatigue . 34 Paragraph 1.1 of the Tribunal's decision, and its reference to "significant contribution", reflected the terms of the definition of "disease" in s 5B of the SRC Act, and not the definition of "disease" in s 4(1) of the Act that was in force at the time the applicant stated that she first sought medical treatment, which as I have mentioned referred to contribution by employment "in a material degree". The Tribunal's order contained an indorsement as follows - The Tribunal NOTES the parties' agreement as to the following: 1. Chronic Daily Headache may have caused symptoms of tiredness or fatigue; and 2. that the Respondent must deduct, or pay, from compensation payable under the SRC Act in respect of the injury: 2.1 any monies payable to Medicare Australia under the Health and Other Services (Compensation) Act 1995 (Cth); and 2.2 any monies payable to the Department of Families, Housing, Community Services and Indigenous Affairs and/or Centrelink under the Social Security Act 1991 (Cth). 35 Subsequently, Comcare determined that the applicant was entitled to weekly payments for various periods from 30 April 2007 until 27 May 2010. Comcare determined that by operation of the statutory formula in s 20 of the SRC Act, the applicant's entitlement to weekly payments was reduced to $nil from 28 May 2010. 36 For the purposes of calculating the applicant's entitlement to weekly payments, during the course of 2013, Comcare made a number of determinations under s 8 of the SRC Act as to the amount of the applicant's normal weekly earnings for various periods of her incapacity, all of which were calculated by reference to 29.4 average hours worked each week. The determinations were dated 15 May 2013, 27 June 2013, 14 August 2013, and 21 August 2013. Why these determinations occurred in a confusing, piecemeal fashion is not apparent on the material. 37 The applicant requested that Comcare reconsider the determination dated 14 August 2013, and upon that request for reconsideration, the decision was affirmed by Comcare on 23 December 2013. 38 On 5 February 2014, the applicant applied to the Tribunal for review of Comcare's decision to calculate normal weekly earnings on the basis of average hours of 29.4 per week. 39 Separately, on 19 February 2014 the applicant made a claim under ss 24 and 27 of the SRC Act for lump sum payments on the ground of permanent impairment and economic loss, citing the accepted injury as "chronic daily headache", which corresponded to the terms of paragraph 1.1 of the Tribunal's decision of 14 September 2012. 40 On 21 March 2014, Comcare disallowed the applicant's claims for lump sum payments. In its reasons, Comcare stated that the relevant guides for the assessment of impairment, namely the American Medical Association's Guides to the Evaluation of Permanent Impairment, Fifth Edition (AMA5) provided that an assessment was not to be made for "chronic pain conditions, except in the case of migraine or tension headaches". Comcare concluded that the Tribunal in its decision (see [33] above) found that the applicant suffered from "chronic daily headache", and that the Tribunal had not accepted "migraine headache" or "tension headache" as part of the applicant's compensable condition. Upon the applicant's request for reconsideration, Comcare affirmed this decision on 2 July 2014. The reviewing officer provided, as one of the reasons, that AMA5 contained no table for the assessment of a standalone headache not associated with identifiable organ dysfunction. 41 On 31 July 2014, the applicant applied to the Tribunal for review of the decision to reject her claim for lump sum payments, thereby resulting in two extant applications by the applicant to the Tribunal for review of separate decisions of Comcare. The two applications for review were heard together. 42 On 9 December 2015, the Tribunal affirmed Comcare's decision in relation to the calculation of normal weekly earnings under s 8 of the SRC Act, but set aside Comcare's decision in relation to the assessment of permanent impairment. The Tribunal decided that the applicant's degree of permanent impairment was 14%, and that Comcare was liable under ss 24 and 27 of the Act to make payments to the applicant: Wuth and Comcare (Compensation) [2015] AATA 947. 43 Comcare appealed the Tribunal's decision that it was liable to make payments to the applicant under ss 24 and 27 of the SRC Act, and the applicant cross-appealed the Tribunal's decision to affirm the calculation of average weekly hours at 29.4. The appeal and cross-appeal were heard and determined by Rares J, and orders were made on 27 April 2017: Comcare v Wuth [2017] FCA 433; 72 AAR 84. Rares J dismissed the appeal, but allowed the cross-appeal. In relation to the cross-appeal, his Honour's decision turned on a factual finding by the Tribunal that the applicant had actually worked more than 36.75 hours per week in the two week period that constituted the "relevant period" for the purposes of the calculation under s 8 of the SRC Act. His Honour held that the Tribunal had failed to apply this finding to the statutory calculation. In relation to the cross-appeal, Rares J made an order that the Tribunal's decision be set aside and that the following decision of the Tribunal be substituted in lieu thereof - 1. In Application 2014/0673, Comcare's decision on 23 December 2013 is set aside and in substitution the following decision is made: Comcare is liable, under s 19 of the Safety, Rehabilitation and Compensation Act 1988 (Cth), to pay compensation to the applicant in respect of her chronic migrainous headaches, on the basis that the average number of hours worked in each week by the applicant in her employment during the relevant period was 36.75 hours. 44 Rares J dismissed Comcare's appeal from the Tribunal's decision relating to the applicant's impairment assessment under AMA5. Comcare had argued, among other things, that the Tribunal lacked medical qualifications to arrive at its own clinical judgment, and that the Tribunal had failed to accord Comcare procedural fairness by determining for itself a degree of impairment of 14% under AMA5 on the basis of its own "clinical judgment", in circumstances where it decided that the applicant's impairment could not be rated conventionally under the tables in AMA5. The Tribunal's process of reasoning was summarised by Rares J at [46]-[50]. On the two issues that I have identified, Rares J held at [78] that the Tribunal was entitled to make its own assessment of impairment, because it was performing an administrative function which used the assessments made by medical practitioners to arrive at its own assessment. Justice Rares also held that Comcare was not denied procedural fairness, for reasons that his Honour gave at [81]-[85]. 45 Comcare appealed the decision of Rares J to the Full Court. Comcare challenged his Honour's decisions relating to both the calculation of average weekly hours, and the impairment assessment. The Full Court (Siopis, Flick and Perry JJ) rejected the grounds of appeal relating to the calculation of average weekly hours: Comcare v Wuth [2018] FCAFC 13; 260 FCR 89. However, in relation to the impairment assessment the Full Court held that the Tribunal did not accord procedural fairness because it failed to disclose to the parties the prospect that it would invoke Chapter 13 of AMA5, upon which no indication had been given as to its potential significance. 46 The consequences of the Full Court's decision and the orders which it made on 18 April 2018 were as follows. First, the orders of Rares J set out under [43] above relating to the calculation of the average number of weekly hours were not disturbed. Second, in allowing the appeal in part, the Full Court ordered that the matter involving the impairment assessment be remitted to the Tribunal for reconsideration according to law. 47 The next relevant event is that on 11 May 2018, which was less than one month after the Full Court's decision, Comcare made another decision involving the calculation of the applicant's normal weekly earnings. By this decision, Comcare did not calculate the applicant's normal weekly earnings by reference to the average weekly hours of 36.75 that had been the subject of the orders of Rares J. Rather, Comcare invoked s 8(5) of the SRC Act and decided that the calculation of normal weekly earnings under s 8(1) of the Act "would not fairly represent the weekly rate at which the employee was being paid in respect of his or her employment before the injury", and instead decided that "a reasonable period would be 29.4 hours per week based on the terms and conditions of [the applicant's] employment that applied to [the applicant] before [her] injury". It is not altogether clear to what actual period Comcare was referring in its reasons, unless it was intended to refer to the whole of the applicant's period of employment following her relocation to the Department of Finance and Administration and prior to the onset of her injury. This resulted in normal weekly earnings being determined at $1,260.38. The decision was affirmed by Comcare on 27 July 2018 upon a request by the applicant for reconsideration. 48 I pause to observe that it does not appear from the material that Comcare had sought to raise or to invoke s 8(5) of the SRC Act at any prior point in time in calculating the applicant's normal weekly earnings. In relation to the calculation of the applicant's normal weekly earnings, and after a reconsideration by Comcare, an unsuccessful application by the applicant to the Tribunal for review, a successful cross-appeal resulting in the orders of Rares J referred to at [43] above, and after successfully resisting Comcare's appeal of those orders to the Full Court, by 27 July 2018 the applicant was back to where she was on 14 August 2013, when Comcare determined that the applicant's normal weekly earnings were to be calculated by reference to 29.4 hours per week. 49 On 27 July 2018, the applicant applied to the Tribunal to review Comcare's reviewable decision of the same day to calculate her normal weekly earnings by reference to 29.4 weekly hours pursuant to s 8(5) of the SRC Act. This resulted in two applications by the applicant to the Tribunal that were on foot at that time - (1) 2014/4007 - the application relating to the impairment assessment that was remitted by the Full Court by its orders of 18 April 2018; and (2) 2018/4238 - the application for review of Comcare's decision of 27 July 2018 in relation to the calculation of normal weekly earnings.

The Tribunal's decision 50 The Tribunal heard and determined both matters together, giving its decision on 3 September 2020 supported by one statement of reasons that addressed both applications for review. The principal finding made by the Tribunal was that the applicant had not suffered a compensable injury for the purposes of the central provision in s 14 of the SRC Act. It will be recalled that by the decision made 14 September 2012 to which I referred at [33] above, the Tribunal decided, with the agreement of the parties, that Comcare was liable to pay compensation to the applicant pursuant to s 14 of the Act in respect of chronic daily headache, which necessarily entailed a finding of compensable injury. The Tribunal's decision that the applicant had not suffered a compensable injury had the result that the applicant did not qualify for any payments of compensation, whether they be lump sum payments under ss 24 and 27, or weekly payments under s 19 of the Act. I pause to note that Comcare, by its counsel, informed the court that Comcare would not seek to recover payments that had previously been made to the applicant on the ground that there was no injury, and therefore no liability to pay compensation to the applicant. 51 The Tribunal conducted an oral hearing over two days, and received written submissions from counsel appearing for the applicant and for Comcare. In addition to the written material that was before the Tribunal, the Tribunal heard evidence. The applicant gave evidence, and the Tribunal found her to be a witness of truth, as had the Tribunal on the first occasion in Wuth and Comcare (Compensation) [2015] AATA 947. The Tribunal also heard evidence by telephone from two medical witnesses, A/Prof Paul Darveniza, who was a medico-legal witness engaged on behalf of the applicant, and Dr Ross Mellick, who was a medico-legal witness engaged on behalf of Comcare. There was also other medical evidence before the Tribunal in the form of written medical reports, including from treating medical practitioners. Those written reports included the report of A/Prof Garrick dated 14 September 2009, to which I referred earlier, in which he stated that the applicant's headaches, "originate from an inflammatory process but are now based on persisting disordered neurotransmission". The contested medical issues included whether the applicant's injury continued to be causally connected in any material degree to the applicant's employment. On that issue, the Tribunal preferred the evidence of A/Prof Darveniza, whose evidence the Tribunal described as lucid, rational, and persuasive. 52 A/Prof Darveniza's report dated 2 December 2019 that was before the Tribunal was written on the premise that Comcare had accepted that the applicant had suffered from the condition of chronic daily headaches as of 27 February 2007. It appears from the transcript of the hearing before the Tribunal on 17 February 2020 that Comcare sought to put the question of injury in issue at a very late stage, and notwithstanding its previous acceptance of liability as reflected in the Tribunal's orders of 14 September 2012 to which I referred earlier. 53 The question whether the applicant's condition was a manifestation of any physiological change was a topic on which A/Prof Darveniza was questioned. In cross-examination, he gave the following evidence about that issue, which it is desirable to set out, with added emphases where appropriate - Q: So let's just work this through. There was no physiological change that was caused by her work in the first place, was there? A: Well, I think there was. Q: Well, what was it? A: The physiological changes that gave her headaches, that's a physiological change. Q: But what is the change to the body? A: What you mean in, well, organic terms? Q: Yes, because all the scans that have come back (indistinct) A: No one knows (indistinct). Q: All the scans have come back normal, right? A: Yes, well they are usually in migraine. Q: Okay. And so --- ? A: We're not dealing with a brain tumour or something like that, that's true. Q: That's right, so we can't see anything there, right? A: Yes. … Q: Yes, good. And then we have subjective reported symptoms of headache, yes? A: Yes. Q: But you can't explain what physiological change has actually occurred --- ? A: No one can. Q: Right, so you have no proof of the physiological change? A: No one can, you know, describe the physiological change. Q: Right? A: That's all speculation. But because someone can't describe it doesn't mean to say it doesn't exist. Q: But you can't point to the actual damage --- ? A: I can't but no one can. Q: Right, we just have subjectively reported symptoms absent of physical change, don't we? A: Yes, exactly, yes. Classically the MRI of the head, as you've said, is normal in migraines, you know. Q: That's right. And so --- ? A: And it's not (indistinct) disorder, you know. Q: And so absent that change you can't say that there's anything that occurred at work that permanently aggravates --- ? A: (Indistinct) something did occur at work. Q: Well, you have a story but you don't have proof that there is a physiological change that is permanent and made worse by employment, do you? A: Well, no one can explain the physiological changes unless you can. Q: And so the answer to my question is no, isn't it? A: No, I don't know whether you can but perhaps you can. Q: And so you can't say or --- ? A: But no one can, I keep saying that to you. Q: That's right? A: No one can explain the physiological changes that cause a migraine because there's no structural pathology found on MRI of the head. There is some stuff with this Monoclonal antibody, the protein factor goes up during acute attacks but no one knows why, why certain things will provoke it. So to say because you can't have a physiological explanation for something that it doesn't exist I think is a false analogy. Q: Well, you may think that, doctor. But the point of this is that you can't point to the physiological change and nor can --- ? A: And neither can you. Q: And nor can medical science? A: And nor can medical science exactly. 54 In re-examination, A/Prof Darveniza gave additional evidence. He confirmed that he had practised for 40 years as a neurologist, and stated that he had vast experience in the management of migraine. He then stated as follows - Q: [T]his is not the only area of medicine where there are - you cannot find physiological change in diagnosing a condition. … A: That's correct, there are numerous diseases where the investigations are normal and rely on the history, you know. Q: Well, doctor, you don't need to be a psychiatrist to know that psychological disorders don't have physiological signs, do they? A: Often they don't, that's correct. Q: So is what you're doing making a clinical judgment based upon the history and the validation of that history from your own experience and other cases you've treated, is that sort of what you - - -? A: That's correct, thank you. Q: Right. So in this case can I use this concept? People talk about a degree of confidence in their findings about some things. Do you have any assessment of what degree of confidence you would apply to your judgment that the employment of this lady in that situation of the history she gave? A: Well, I'd be pretty confident that in 90 per cent of patients that I see that have undertaken the history of examination I know what's going on. Q: Right. But in terms of your judgment about this lady, that her condition is connected with her employment with the Department of Finance and the stress and workload she applied? A: Yes. 55 The Tribunal found that the applicant suffered from headaches from about 2005, and that the evidence consistently pointed to the work-related events of 2007 as constituting an aggravation or exacerbation of the applicant's underlying condition, which was described by one medical practitioner as "post-chronic fatigue syndrome". 56 The Tribunal found at [66] of its statement of reasons that the applicant "continues to suffer from chronic daily headaches which, on the balance of probabilities, are still materially contributed to by her former employment with the Department". And at [69], the Tribunal stated that it found that the applicant "still suffers chronic daily headaches and that her former employment still makes a material contribution to that condition". These critical findings were supported by the opinion of A/Prof Darveniza. 57 The Tribunal then turned to address a submission made by Comcare that, by reference to the reasons in the joint judgment in Military Rehabilitation and Compensation Commission v May [2016] HCA 19; 257 CLR 468 (MRCC v May), there was no physiological change that accounted for the applicant's condition, and that therefore there was no injury for the purposes of the SRC Act. On this question, the Tribunal stated - 75. It was common ground between the parties in these proceedings that no physiological change can be identified in Ms Wuth which accounts for her headache condition. Prof Darveniza told the Tribunal that the condition can be ascertained by the history that Ms Wuth has provided, not by physiological change. Comcare submitted that her condition can be described as a collection of subjectively reported symptoms without an accompanying identifiable physiological change or disturbance, and that this places her condition squarely within the category which the High Court determined in May could not amount to an injury pursuant to the Act (at [57]). 76. This Tribunal accepts that contention. It is difficult to characterise the words of their Honours in any other way than as precluding such conditions from compensability. I reach this view, however, with some trepidation, for two reasons. 77. The first is that this conclusion throws into question a line of previously decided cases where the existence of symptoms, notwithstanding that there was no alteration of the underlying pathology, was found to amount to an injury for the purposes of the Act: this line includes Federal Broom Co Pty Ltd v Semlitch [1964] HCA 34; Commonwealth v Beattie [1981] FCA 88; Tippett v Australian Postal Corporation [1998] FCA 335; Mellor v Australian Postal Corporation [2009] FCA 504; Comcare v Reardon [2015] FCA 1166; Military Rehabilitation and Compensation Commission v Katterns [2017] FCA 641; Howard v Comcare [2019] FCA 1031; and (to a certain extent) Australian Postal Corporation v Lucas [1991] FCA 612. Similarly, in the Tribunal there is a line of decisions (some decided after May) where pain conditions of uncertain origin or diagnosis have been found to be ailments within the meaning of s 5B: Hopkins and Comcare [2016] AATA 742; Cosgrove-Kaye and Comcare [2019] AATA 1238. 78. The second basis for the Tribunal's trepidation is that, in practical terms, a large number of physical and psychiatric conditions in the workers' compensation jurisdiction which are presently taken to be compensable when they have their origins in employment would no longer be so categorised. This may be viewed by some as an affront to common sense. As counsel for Ms Wuth so succinctly put it, a person trying to argue at a medical conference that headaches do not exist because no specific "physiological change" has been identified would be laughed out of the room. One conspicuous casualty of this new approach could be psychiatric conditions, for which there is generally no physiological evidence. 58 It was accepted on this appeal that it was never common ground between the parties before the Tribunal that no physiological change could be identified: counsel for the applicant before the Tribunal had made no such concession. The Tribunal's reference at [75] of its reasons to "common ground between the parties" is more likely a reference to the Tribunal's understanding of the medical evidence of A/Prof Darveniza and Dr Mellick. However, counsel for the applicant submitted that in the absence of the claimed error of law based upon the Tribunal's misapplication of MRCC v May, the inaccuracy as to what was common ground would not have affected the decision, or have been material. The other material feature of the Tribunal's finding at [75] and [76] is that the Tribunal accepted a submission that there was no identifiable physiological change or disturbance. I will come back to address the relevance of that finding when considering whether the Tribunal addressed itself to the correct question. 59 The Tribunal's finding that there was no compensable injury was held to be sufficient to decide both the review relating to the impairment assessment, and the review relating to the calculation of the applicant's normal weekly earnings. It is a curiosity that, notwithstanding the Tribunal's determination that there was no "injury", the Tribunal affirmed Comcare's decision of 27 July 2018 which proceeded on the basis of an accepted claim, and which determined that the applicant's normal weekly earnings were $1,260.38. 60 Notwithstanding its finding that there was no injury, the Tribunal proceeded to consider other issues in the event that it was wrong in deciding that "chronic daily headache" did not constitute a compensable injury under the SRC Act. 61 In relation to whether the applicant had an impairment that was permanent, the Tribunal did not accept that the applicant's claimed impairment was permanent. The Tribunal accepted the evidence of A/Prof Darveniza that there was a monoclonal antibody treatment that had recently become available which might provide some chance of significant improvement in the applicant's condition. The Tribunal found that the applicant had not attempted this treatment, and that it was reasonable for her to undertake such treatment. 62 In addition, the Tribunal held that the medical evidence before it, and in particular the evidence of A/Prof Darveniza who assessed the applicant's level of impairment at 30%, did not enable it to arrive at an impairment assessment. That was principally because the evidence did not rise to the level required by the Full Court in Comcare v Wuth, and ultimately, the Tribunal held that the evidence of A/Prof Darveniza did not disclose a logical process by which he reached his conclusion, and that there was no other evidence before it of an assessment meeting the requisite standard. 63 The Tribunal addressed another submission that was advanced before it on behalf of Comcare at a very late stage of the review, which was that the SRC Act did not apply to the applicant because notice in writing of the injury had not been given as soon as practicable after the applicant became aware of the injury, which was a condition of s 53(1) of the Act. Comcare had submitted to the Tribunal that the applicant had been aware of the role of her employment in the development of her injury in early 2007, but had not made a claim until April 2010, with the consequence that Comcare had been prejudiced. The Tribunal rejected this submission on the grounds of procedural fairness, noting that Comcare had not previously taken this point over the years that the claims had been on foot, had not raised the point in its statement of facts issues and contentions, and had not adverted to the point explicitly during the hearing, thereby denying the opportunity to hear evidence that might bear upon the issue. 64 As a consequence of the Tribunal's finding that there was no injury, the Tribunal held that it was unnecessary to consider the applicant's application for review of Comcare's 2018 decision relating to the calculation of normal weekly earnings for the purposes of calculating any entitlement to weekly payments under s 19 of the SRC Act, where Comcare had invoked s 8(5) of the Act following the Full Court's decision in 2018. Nonetheless, on that application the Tribunal held that it would have rejected Comcare's submission that s 8(5) of the Act would have disentitled the applicant to payments based upon the hours actually worked in the relevant period before her injury. The Tribunal purported to rely on reasoning of Rares J and of the Full Court which, for the purposes their Honours' consideration of the calculation required by s 8(1) of the Act, directed attention to hours worked rather than hours for which the applicant was paid. After setting out some passages from the reasons of Rares J and the Full Court the Tribunal concluded - 118. It must be noted that neither court had before it (in contrast to this Tribunal) an explicit submission with respect to the operation of s 8(5). However, all three of the cited judgements make reference to s 8(5), and it seems obvious that the effect of the section was within the contemplation of their Honours as they reached their decisions. In my assessment, it is fair to infer from the reasoning displayed above that they would similarly have rejected a submission of Comcare, had it been advanced, that s 8(5) would have disentitled Ms Wuth to impairment payments based on the hours she actually worked in the relevant period before her injury. I come to this view because Comcare's submission before me on s 8(5) again depended on the premise that the period before Christmas 2006 was more representative of the hours she was working than the first two months of 2007, whereas it is implicit in the decisions of their Honours that it was not. 65 The above conclusions are problematic, and I will return to them when addressing the parties' submissions.

The appeal to this court 66 In the appeal to this court the applicant relied on a second further amended notice of appeal (notice of appeal), and Comcare relied on a second further amended notice of contention (notice of contention). An objection to competency by Comcare, which took the form of a "second further amended notice of objection to competency" was abandoned by senior counsel for Comcare during the course of the hearing, and I need not consider it further for the purposes of the disposition of the appeal.

The notice of appeal 67 The notice of appeal raises the following questions of law - 1. On the proper construction of the definitions of "injury", "disease" and "ailment" in section 4 of the Safety Rehabilitation and Compensation Act 1988 ("the SRC Act"), did the Tribunal err in law in accepting that - (a) in a case where the Applicant contended that she suffered from a "disease", namely "chronic daily headache", being an "ailment" which had been contributed to in a material degree by her employment with the Commonwealth; and (b) did not suffer from "an injury (other than a disease)"; it was necessary that the Tribunal should be satisfied that the Applicant's "ailment" demonstrated an "identifiable physiological change or disturbance", in order to amount to an "injury" pursuant to the SRC Act. See paragraphs [75]-[76] of the Tribunal's reasons for decision[.] 2. Are the factual findings set out in paragraphs [1], [3], [61], [66] and [69], to the effect that - (a) the Applicant still suffered the "ailment" of chronic daily headache; and (b) her former employment still made a material contribution to that "ailment"; sufficient to establish, as a matter of law, that the Applicant had suffered the "disease" of chronic daily headache under the SRC Act, and continued to suffer from that "disease" at the time of the Tribunal's decision? 3. Having regard to the answers to Questions 1 and 2 above, the Applicant's history of incapacity, treatment and impairment summarised in paragraphs [1]-[3] and [16]-[23] of the Tribunal's reasons for decision, and the explicit finding by the Tribunal in paragraph [114] that the Applicant was a witness of truth, is the Applicant entitled, as a matter of law, to compensation under section 14 of the SRC Act in respect of her chronic daily headache? 4. Having regard to the answers to Questions 1, 2 and 3 above, and the decision of the Full Court in Comcare v Wuth (2018) 260 FCR 89, are the findings set out at paragraph [118] of the Tribunal's reasons for decision sufficient to establish, as a matter of law, that the Applicant is entitled to compensation under section 19 of the SRC Act in respect of her chronic daily headache, on the basis that the average number of hours worked in each week by the Applicant in her employment during the relevant period was 36.75 hours? 68 For the purposes of ground 3, set out above, the applicant sought to have the court make a finding of fact under s 44(7) of the Administrative Appeals Tribunal Act as follows - If it be necessary, in the absence of agreement from the Respondent, the Court is respectfully requested to make a finding of fact under sub-section 44(7) of the Administrative Appeals Tribunal Act 1975 for the purpose of answering Question 3 above, that on the evidence before the Tribunal, the Applicant suffered from incapacity for work, a need for treatment, or impairment as a result of her "disease" of chronic daily headache. 69 The corresponding grounds of appeal are as follows - 1. On the proper construction of the definitions of "injury", "disease" and "ailment" in section 4 of the SRC Act, as interpreted by the High Court of Australia in Military Rehabilitation and Compensation Commission v May (2016) 257 CLR 468, the Tribunal erred in law by misunderstanding the statutory requirements in the SRC Act for a finding that the Applicant suffered from a "disease", which at the relevant time in the present case - (a) required only findings of fact by the Tribunal that the Applicant suffered from an "ailment" which was contributed to, to a material degree, by the Applicant's employment with the Department of Finance ("the Department"); and (b) did not additionally require that there should be an "identifiable physiological change or disturbance" for the Applicant's diagnosed condition of "chronic daily headache" to be an "ailment". 2. The Tribunal erred in law in failing to find that the Applicant's "chronic daily headache" ailment was an ongoing "disease" for the purposes of the SRC Act, having found as a matter of fact that, at the time of its decision - (a) the Applicant continued to suffer from "chronic daily headaches"; and (b) on the balance of probabilities, the "chronic daily headaches" were still materially contributed to by her former employment with the Department. 3. Having erred in law in the matter set out in Ground 1 and Ground 2, the Tribunal made consequential errors of law in failing to find that the Applicant was entitled to compensation in respect of chronic daily headache - (a) under section 14 of the SRC Act; and (b) under section 19 of the SRC Act, calculated on the basis that the average number of hours worked in each week by the Applicant in her employing during the relevant period was 36.75 hours. 70 In essence, all the questions of law and grounds of appeal raised by the applicant are founded on a claim that the Tribunal misinterpreted the reasons in the joint judgment in MRCC v May as requiring that there be an identifiable physiological change in order for there to be a "disease" qualifying as an "injury" under the SRC Act, as in force at the relevant time. 71 The applicant sought the following substantive relief - 1. The decision of the Tribunal in AAT Matter 2018/4238 is set aside and in lieu thereof, the following orders or declarations are substituted: "1. The Respondent is liable under section 14 of the Safety, Rehabilitation and Compensation Act 1988 (Cth) (the SRC Act) to pay compensation to the Applicant in respect of 'chronic daily headache'. 2. The Respondent is directed to calculate any amounts payable to the Applicant under any of sections 19, 20, 21 or 21A, on the basis that the average number of hours worked in each week by the Applicant in her employment during the relevant period was 36.75 hours." 2. In the alternative to Orders 1 and 2 - the decision of the Tribunal in AAT Matter 2018/4238 is set aside, and the matter is remitted to the Tribunal for determination according to law.

The notice of contention 72 By its notice of contention, Comcare initially raised five contentions, the fourth of which was abandoned during the hearing. The remaining contentions are as follows - 1. Applying the terms of s 8(5) of the Safety, Rehabilitation and Compensation Act 1988 (Cth) (SRC Act), the Tribunal should have concluded that the Applicant's normal weekly earnings (NWE) as calculated in relation to the relevant period under s 8(1) did not fairly represent the weekly rate at which she was being paid in respect of her employment before her alleged injury. The Tribunal should have calculated the Applicant's NWE on the basis of another period which fairly represented the weekly rate at which she was being paid in respect of her employment before the alleged injury. On the facts, that was the period "before Christmas 2006". 2. Further or in the alternative, the Tribunal erred in law in refusing or failing to consider Comcare's submissions as to the application of s 8(5) and/or (10) of the SRC Act. The Tribunal should have considered and engaged with Comcare's submissions as to the application of s 8(5) and/or (10) of the SRC Act in the Applicant's circumstances. If the Applicant were to succeed on an issue in her appeal (which Comcare opposes), the matter should be remitted to the Tribunal for it to consider and engage with Comcare's submissions and, where appropriate, apply s 8(5) and/or (10) of the SRC Act in the Applicant's circumstances. 3. Further or in the alternative, the Tribunal mischaracterised or misunderstood the nature of Comcare's submissions in relation to s 8(5) and/or (10) of the SRC Act. If the Applicant were to succeed on an issue in her appeal (which Comcare opposes), the matter should be remitted to the Tribunal for it to consider and engage with Comcare's submissions and, where appropriate, apply s 8(5) and/or (10) of the SRC Act in the Applicant's circumstances. 4. … 5. Further or in the alternative, despite the matters set out in first to fourth questions of law and grounds 1 to 3 of the Applicant's second further amended notice of appeal, the evidence before the Tribunal was effectively that the Applicant's alleged headaches amounted to subjectively reported symptoms without an accompanying physiological change. That evidence cannot establish an "ailment" or an "injury (other than a disease)" under the SRC Act. 73 In summary, and taking these contentions in a different order, Comcare claims that the Tribunal did not engage with its submissions about the effect of s 8(5) and (10) of the SRC Act, or alternatively misunderstood those provisions. Comcare invites this court to apply s 8(5) of the Act in the way Comcare contends the Tribunal should have, or alternatively to remit the matter to the Tribunal to engage with its submissions. The fifth contention was not abandoned, but did not appear to be developed in argument. It is not clear that it adds anything to Comcare's resistance to the grounds of appeal raised by the applicant.

The applicant's submissions 74 Counsel for the applicant submitted that the Tribunal erred in treating the decision of the High Court in MRCC v May as laying down a requirement that a physiological change had to be demonstrated in order to be entitled to compensation under the SRC Act in respect of a disease. Counsel for the applicant submitted that MRCC v May was concerned with the construction of the phrase "injury (other than a disease)" within the definition of "injury" in s 4(1) of the Act, and not with the meaning of the term "disease", which was separately defined to be an ailment, or an aggravation of an ailment, which in turn directed attention to the defined term "ailment", which do not state any requirement that there be physiological change. These submissions require that careful attention be given to what was decided in MRCC v May, which I will address later. Counsel for the applicant submitted that there was no requirement under the legislation that there be shown some physiological change in order to demonstrate that there is an ailment. 75 Counsel for the applicant also submitted that by [75] of its reasons the Tribunal found that no physiological change could be identified, which was not the same thing as saying that there was no physiological change. Counsel submitted that the Tribunal had erred in treating MRCC v May as requiring that there be shown a physiological change, that is to point to an identified physiological change. The nature of this error was highlighted by the concurrent findings by the Tribunal which otherwise accepted that the applicant suffered chronic daily headaches to which her former employment continued to make a material contribution. 76 As to the consequential issues, counsel for the applicant relied on the Tribunal's findings of fact in relation to the applicant's condition to which I referred at [55] above, and submitted that on the basis of those findings the applicant had as a matter of law suffered an "injury" as defined by s 4(1) of the SRC Act. 77 Counsel for the applicant submitted that were it not for the Tribunal's finding that the applicant had not suffered an "injury", it would have found in the applicant's favour in relation to the calculation of normal weekly earnings as was apparent from its express reasons on that question, to which I referred at [64] above. On the assumption that the applicant was successful, counsel submitted that this court should grant to the applicant the relief to which she would have been entitled from the Tribunal, thus bringing to an end years of litigation between the applicant and Comcare. In the event that it was necessary to make further findings of fact, it was submitted that the court should do so, exercising its powers under s 44(7) of the Administrative Appeals Tribunal Act. 78 For completeness, there are two aspects of the submissions of counsel for the applicant that should be noted. First, counsel accepted that in accordance with the decision of the Full Court in Telstra Corporation Ltd v Hannaford [2006] FCAFC 87; 151 FCR 253 at [59] (Conti J, Heerey J and Dowsett J agreeing), it was open to the Tribunal to make a finding that the applicant had not suffered an "injury" as defined by s 4(1) of the SRC Act in undertaking its review of the two determinations of Comcare. No challenge was made to this aspect of the Tribunal's decision. Secondly, there was no challenge to the Tribunal's decision so as to suggest that there was any error to the extent that its finding that the applicant had not suffered an "injury" in its defined sense was inconsistent with the Tribunal's earlier determination of 14 September 2012 that the applicant had suffered a disease, and to which I referred at [33] above. In this context, reference should be made to s 62 of the Act, set out at [21] above, which authorises reconsideration of determinations by the person who made the determination, and to the Full Court's decision in Commonwealth v Snell [2019] FCAFC 57; 269 FCR 18 (Allsop CJ, Reeves and Derrington JJ), which held that the principles of issue estoppel are inapplicable, albeit in the context of a claim under the Seafarers Rehabilitation and Compensation Act 1992 (Cth).

Comcare's submissions 79 Counsel for Comcare submitted that the requirement stemming from the High Court's decision in MRCC v May that there be a physiological or psychiatric change in order that there be an injury was not confined to "an injury (other than a disease)". Counsel submitted that it was clear from [57] of the joint reasons in MRCC v May that the requirement that there be a physiological change applied to both limbs of the definition of "injury" in s 4(1) of the SRC Act. Counsel submitted that this understanding of MRCC v May was consistent with earlier decisions, namely Canute v Comcare [2006] HCA 47; 226 CLR 535 (Gummow ACJ, Kirby, Callinan, Heydon and Crennan JJ), and Comcare v Mooi (1996) 69 FCR 439 (Drummond J). 80 In relation to the Tribunal's reasons at [75], counsel for Comcare submitted that the Tribunal's finding that no physiological change could be identified was a finding of fact that corresponded to the questions identified in the joint judgment in MRCC v May at [57], and which did not involve any error or misunderstanding by the Tribunal. Counsel submitted that on the assumption that no physiological change could be identified that would account for the applicant's headaches, the Tribunal was bound to find that there had been no "injury" for the purposes of s 14 of the SRC Act. 81 In relation to the issues raised by the notice of contention, counsel for Comcare submitted that the Tribunal erred in law in its consideration of the issues relating to its review of Comcare's invoking s 8(5) of the SRC Act, by failing to consider relevant and probative material in relation to its application. In particular, it was submitted that the Tribunal failed to give attention to the question raised by s 8(5) which was whether the normal weekly earnings calculated in accordance with s 8(1) or (2) would fairly represent the weekly rate at which the applicant was paid in respect of her employment before the injury, in which event normal weekly earnings are to be calculated in relation to such other period as Comcare considers reasonable. Counsel relied on submissions that had been made to the Tribunal that, to focus on a two week period of employment leading up to the applicant's deemed date of injury, produced a normal weekly earnings amount that did not fairly represent the weekly rate at which the applicant was being paid, and that the appropriate course was to select the period before Christmas 2006, where the applicant had spent four weeks working four-fifths of a fulltime workload, and was paid as such. Counsel submitted that rather than performing its function, the Tribunal expressed views based upon what it thought was within the contemplation of the Full Court in Comcare v Wuth when it decided a question under s 8(1) of the SRC Act, essentially misquoted Comcare's submissions, engaged in conjecture as to what the Full Court would have made of Comcare's submissions in reliance on s 8(5), failed to appreciate that s 8(5) is concerned with the weekly rate at which the applicant was paid, rather than hours worked, and failed thereby to direct itself to the case that Comcare had advanced before it. 82 The primary relief which counsel for Comcare sought was an order dismissing the appeal. It was submitted in the alternative that it would be appropriate to remit the matter to the Tribunal for reconsideration. In the further alternative, it was submitted that even if the applicant were to be successful, the court should not make declarations as sought by the applicant.

Did the applicant suffer an injury? 83 The submissions of the parties to this appeal require close attention to the reasons in the joint judgment of French CJ, Kiefel, Nettle and Gordon JJ, and the separate reasons of Gageler J in MRCC v May. Before considering those reasons for judgment, I will briefly highlight some of the features of workers' compensation legislation, and the SRC Act in particular, the relevant provisions of which I have already set out. 84 The definition of "injury" in s 4(1) of the SRC Act has two distinct sub-sets - (a) a disease [as defined]; and (b) an injury (other than a disease). 85 The word "injury" in paragraph (b) is used in its primary sense, and part of the legislative context is a body of High Court authority that over the years has considered the meaning of the term "injury" in different workers' compensation statutes. For the purposes of s 4(1) of the SRC Act, the court's decision in MRCC v May is the relevant binding authority on the meaning of the word "injury" in its primary sense. 86 The word "disease" is defined, and where used in paragraphs (a) and (b) of the definition of "injury" carries its defined meaning: Australian Postal Corporation v Burch (1998) 85 FCR 264 (Burch) at 267-268 (Heerey, Sundberg and North JJ); MRCC v May at [54] (French CJ, Kiefel, Nettle and Gordon JJ), and [72] (Gageler J). It is an important element of the defined meaning of "disease" that there be an ailment or aggravation of an ailment that "was contributed to in a material degree" by the employee's employment. What is required is that employment be a material contributing factor, and not merely a temporal nexus: see, Comcare v Canute [2005] FCAFC 262; 148 FCR 232 at [67] (French and Stone JJ). This may be compared to the reference to "injury" in its primary sense in paragraph (b) of the definition of "injury" in s 4(1), which requires that the injury be "a physical or mental injury arising out of or in the course of" the employee's employment. This requires either a causal or a temporal nexus to employment. 87 The different degrees of connection between employment and disease, and employment and injury (other than a disease), render the difference between them important. The fact that they are different, albeit overlapping, concepts is embedded in the SRC Act. As a generalisation, and subject to the following qualifications, for a long time workers' compensation legislation in Australia has required that a distinction be drawn between an injury and a disease because of the different tests connecting them to employment as a condition of liability to pay compensation. However, one must be cautious to generalise, because over the years workers' compensation legislation in the States, Territories, and the Commonwealth of Australia has been frequently amended and re-enacted, and the legislation has not been uniform. For the reasons given by Lord Upjohn in Ogden Industries Pty Ltd v Lucas [1970] AC 113 at 127, and by McHugh, Gummow and Heydon JJ in McNamara v Consumer Trader and Tenancy Tribunal [2005] HCA 55; 221 CLR 646 at [40], it is necessary to pay attention to the terms of the legislation and the facts under consideration in each case so that judicial formulations apt to explain the proper construction of one particular form of the legislation are not uplifted and employed to take the place of the text of differently framed provisions: see also, Kennedy Cleaning Services Pty Ltd v Petkoska [2000] HCA 45; 200 CLR 286 (Kennedy Cleaning) at [22] (Gleeson CJ and Kirby J) and [59] (McHugh, Gummow and Hayne JJ). Subject to that qualification, I will now refer briefly to some of the issues considered by the High Court in cases that preceded the decision MRCC v May. 88 A recurring issue that arose over the years was whether a change in physiology as the outcome of an underlying disease, such as heart disease, qualified as an "injury" in its primary meaning. As I have alluded to, the issue arose because of the different degrees of connection required by the legislation between "injury" and employment, and "disease" and employment. There have been a number of cases where an employee suffered from underlying degenerative heart disease and where it was held the rupture of a blood vessel caused by exertion in the course of employment was an "injury by accident". It was in one such case that Clauson LJ stated that, "a physiological injury or change occurring in the course of a [person's] employment by reason of the work in which he is engaged at or about that moment is an injury by accident arising out of his employment, and this is so even though the injury or change be occasioned partly, or even mainly, by the progress or development of an existing disease…": Oates v Earl Fitzwilliam's Collieries Co [1939] 2 All ER 498 at 502, cited in Hetherington v Amalgamated Collieries of WA Ltd (1939) 62 CLR 317 at 328 (Latham CJ) and 334 (Dixon J). The requirement of a "sudden physiological change" was referred to in some of the authorities to establish an "injury by accident" in the course of employment: see, James Patrick & Co Pty Ltd v Sharpe [1955] AC 1 at 15 (Lord Reid); Commonwealth v Hornsby (1960) 103 CLR 588 at 592-594 (Dixon CJ). In these contexts, a physiological change that occurred in the course of employment as a result of some specific act of exertion that was an incident of employment was capable of being regarded as an injury by accident, and distinguished the event from the natural progression of a pre-existing disease unrelated to employment and which therefore was not compensable. 89 In Hume Steel Ltd v Peart (1947) 75 CLR 242 at 252, Latham CJ drew a distinction according to common use of language between "getting hurt" and "becoming sick", stating that "[t]he former would be described as an injury and the latter would generally not be so described". While this formulation might be useful in seeking to conceptualise the difference between an injury and something that is not an injury, it cannot take the place of the statutory language. For one thing, an injury in its primary sense is not confined to "getting hurt". In seeking to identify the characteristics of a disease, in Favelle Mort Ltd v Murray (1976) 133 CLR 580 (Favelle Mort) Barwick CJ stated at 587-588 - The word "disease" is itself a word of some difficulty in this context, particularly in the expression "contraction of a disease". Properly used, disease denotes a morbid condition of the body. It may be initiated by some external cause or be idiopathic or autogenous. Quite clearly, when such a condition is idiopathic or autogenous, it will not qualify as an injury in the normal use of language. 90 The above passage, save for the last sentence, was cited in Zickar v MGH Plastic Industries Pty Ltd [1996] HCA 31; 187 CLR 310 (Zickar) at 334 (Toohey, McHugh and Gummow JJ), adding that "the word [disease] must be seen in the context in which it appears and be related to the circumstances of the case". Both Favelle Mort and Zickar concerned New South Wales workers' compensation legislation. For the purposes of the SRC Act, attention must be given to the definition of "disease", and in turn the definition of "ailment" in s 4(1), however the passage from Favelle Mort is helpful in identifying what is not an "injury" in its primary sense. 91 The High Court's decision in Kennedy Cleaning concerned a claim made under the Workers' Compensation Act 1951 (ACT). The worker suffered a stroke while at work that resulted in incapacity for work. Prior to the occurrence of the stroke, the worker had been diagnosed with an underlying heart condition that was liable to lead to an embolism. The question in issue was whether the worker had suffered "personal injury" arising out of or in the course of her employment, in which case the worker was entitled to compensation under s 7(1) of the Act; or whether the worker suffered only a "disease" which attracted s 9(1) of the Act, which it was accepted could not be engaged because the medical evidence did not support a conclusion that the employment was a "contributing factor" to the contraction of the disease. The court by majority upheld the entitlement to compensation. In their joint reasons, Gleeson CJ and Kirby J stated - 35. … a long line of decisions in Australia had recognised that an "injury", being a sudden or identifiable physiological change, could nonetheless qualify within the ordinary application of that expression appearing in workers' compensation legislation, although the change was internal to the body of the worker. It did not have to be external or necessarily produced by external causes. Moreover, the inclusion in the definition of "injury" in s 6(1) of the Act of "mental injury" makes it plain beyond argument in this case that the injuries for which the Act provides are not confined to those originating externally to the body of the worker. [Footnote omitted.] 36. Secondly, the mere fact that a sudden physiological change is in some way connected with an underlying "disease" process does not, of itself, prevent the classification of such a change as an "injury" within the primary statutory provisions that apply to such a case. … 92 Later, Gleeson CJ and Kirby J referred to the approach in three earlier cases, Accident Compensation Commission v McIntosh [1991] 2 VR 253, Zickar, and Burch, and stated of them - 39. … All of those cases require that consideration be given to the precise evidence, on a fact by fact basis, concerning the nature and incidents of the physiological change accepted at trial. If this evidence amounts, relevantly, to something that can be described as a sudden and ascertainable or dramatic physiological change or disturbance of the normal physiological state, it may qualify for characterisation as an "injury" in the primary sense of that word. … 93 It is necessary to identify the facts in MRCC v May, and the issue to which they gave rise. Mr May had become significantly disabled by dizziness, or vertigo, and had been discharged from the Royal Australian Air Force (RAAF). Mr May claimed that he had been required to undergo vaccinations to which he had experienced adverse reactions. However, specialists who had examined Mr May had been unable to diagnose any specific condition, or determine a cause for his symptoms. One of the specialists described Mr May's symptoms as a "functional somatic disorder": MRCC v May at [18]. Mr May applied for compensation under the SRC Act. Like the present case, the relevant terms of the SRC Act applicable to Mr May's claim were those prior to the 2007 amendments. Significantly, the claim was not advanced on the ground that Mr May suffered a "disease" as defined by the SRC Act. If it had been, compensation would have been payable only if Mr May had suffered an ailment, or the aggravation of an ailment, that was contributed to in a material degree by his employment. Instead, Mr May advanced his claim on the ground that he had suffered an "injury (other than a disease)" within paragraph (b) of the definition of "injury" in s 4(1) of the Act, which required that Mr May establish that the injury was "a physical or mental injury arising out of, or in the course of" his employment. 94 Mr May's claim was initially refused. That decision was affirmed upon review by the Tribunal: May and Military Rehabilitation and Compensation Commission [2011] AATA 886. The Tribunal made a number of findings that were summarised in the joint judgment in MRCC v May at [16]-[29] and [66]-[67]. The Tribunal concluded that Mr May had failed to establish his case, holding that there was no medical evidence to establish a connection between Mr May's vertigo and the vaccinations that he received while in the RAAF. Nor in the Tribunal's view was there objective evidence connecting some of Mr May's other claimed symptoms with the vaccinations. Although Mr May did not claim compensation on the ground that he suffered a "disease" as defined by s 4(1) of the SRC Act, the Tribunal addressed this question also, concluding that it was not satisfied that Mr May's vertigo was contributed to in a material degree by his employment in the RAAF. 95 Mr May appealed to the court on a question of law. The appeal was dismissed at first instance, but was allowed on appeal to the Full Court: May v Military Rehabilitation and Compensation Commission [2015] FCAFC 93; 233 FCR 397. Amongst other things, the Full Court held at [207] that the Tribunal had been in error in substituting for the statutory concept of "injury" in s 4(1) of the Act a requirement that there be a "sudden or identifiable physiological change", a phrase used in a number of the authorities that sought to differentiate between an injury and an underlying disease, as identified in the reasons for judgment of Gleeson CJ and Kirby J in Kennedy Cleaning at [35] to which I referred above. The Full Court then stated at [209], [211] and [212] (inter alia) - 209 … [O]n the authorities to which we have referred, and the proper construction of "injury" in s 4, there is no basis for the distinction made by the Tribunal between evidence of what it calls "symptoms" and the need for a "diagnosis". As part of the statutory question, one asks whether the person has experienced a physiological change or disturbance of the normal physiological state (physical or mental) that can be said to be an alteration from the functioning of a healthy body or mind. There is no warrant from the statute or the cases to require diagnosis or medically ascertained cause. … 211 … [T]he question the Tribunal should have asked and answered was (in the light of the finding of the onset of vertigo and of all relevant material) whether the appellant suffered an injury, without seeing as essential preconditions a formal diagnosis or objective medical evidence corroborating the physiological changes reported by the appellant. The requirement for objective medical evidence and diagnosis misdirected the enquiry for substantiating material and tended to raise a requirement for an identifiable event or incident or cause that had a connection (of more than a temporal character) with employment. 212 … [N]either the terms of s 4 of the SRC Act, nor the authorities, preclude an injury being established on the basis of an account by a claimant of the disturbances to her or his body or mind, without the necessity for a diagnosis of a recognised medical condition, or corroborating pathology or medical opinion. Whether or not the evidence of a claimant will be sufficient, if it is not supported, corroborated or confirmed by independent medical opinion or pathology, will be a matter for the Tribunal's satisfaction on the evidence in each particular case. … 96 In the High Court, the joint judgment at [3] framed the issue as being whether Mr May's dizziness was an "injury" for the purposes of the SRC Act, and therefore compensable under s 14 of the Act. The appellant, the MRCC, submitted that the concept of "injury (other than a disease)" in paragraph (b) of the definition of "injury" in s 4(1) of the SRC Act required that there be a "sudden or identifiable physiological change": see the joint judgment at [39]-[40]. 97 The joint judgment at [42] identified that the definition of "injury" in s 4(1) of the Act comprises two separate but related sub-sets, having a different meaning in the statutory scheme: (a) "disease"; and (b) "injury (other than a disease)". In relation to the definition of "disease" the joint judgment stated at [43] - 43 As appears from the definition of "disease", a "disease" for the purposes of the Act must be an ailment or an aggravation of an ailment. That is not sufficient to establish the existence of a disease. The ailment or aggravation thereof has to have been contributed to in a material degree by the employee's employment by the Commonwealth. 98 Their Honours stated at [45] that "injury" in paragraph (b) of the definition is used in its primary sense, citing the passage from the reasons of Gleeson CJ and Kirby J in Kennedy Cleaning at [39] which I set out earlier. Their Honours held at [46]-[47] that a physiological change or disturbance of the normal physiological state may be internal or external to the body of the employee, however, "suddenness" is not necessary for there to be an "injury" in the primary sense, although suddenness is often useful to distinguish a physiological change from the natural progress of an underlying disease. In that respect their Honours stated at [47] (inter alia) - 47. …"suddenness" is not necessary for there to be an "injury" in the primary sense. A physiological change might be "sudden and ascertainable". A physiological change might be "dramatic". The employee's condition might be a "disturbance of the normal physiological state". That an "injury" in the primary sense can arise, and can be described, in a variety of ways does not mean that "suddenness" is irrelevant. … [Footnotes omitted.] 99 The joint judgment at [50]-[53] identified that the definition of "injury" in s 4(1) of the SRC Act requires a structured enquiry involving a series of questions, which I will set out, omitting footnotes - 50 First, does the evidence amount, relevantly, to something that can be described as an "ailment", being a physical or mental ailment, disorder, defect or morbid condition? Second, if so, was that state contributed to in a material degree by the employee's employment by the Commonwealth? 51 If the answer to both those questions is "Yes", there is a "disease" within para (a) of the definition of "injury". Of course, in some cases, the answer to those questions may be admitted. That is, the employee may admit that the answer to the first question, or both the first and the second questions, is "No". 52 If there is not a "disease" within para (a) of the definition of "injury", the tribunal of fact next inquires whether there is an "injury (other than a disease)" within para (b). The third question is - does the evidence demonstrate the existence of a physical or mental "injury" (in the primary sense of that word)? Generally, that will be determined by asking whether the employee has suffered something that can be described as a sudden and ascertainable or dramatic physiological change or disturbance of the normal physiological state. However, that judicial language is not to be construed or applied as if it were the words of a statute defining a necessary condition for the existence of an "injury (other than a disease)". The language of judgments should not "be applied literally to facts without further consideration of what is conveyed by the reasoning" in the cases from which it is derived, or without regard to the text and scheme of the Act. 53 If there be an "injury" in the primary sense of the word, the next question is - did that injury arise out of, or in the course of, the employee's employment by the Commonwealth? If that question is answered "Yes", there is an "injury (other than a disease)" within para (b) of the definition of "injury" in s 4(1) of the Act. In some circumstances, if the answer is "No", it may be necessary to ask whether the case is one involving aggravation of an injury. That question does not arise in this appeal. 100 The next three paragraphs of the joint judgment are important because they identify that a physiological change, or a disturbance of the normal physiological state, or a psychiatric disorder, may satisfy the definition of "ailment", and that the "disease" limb remains an additional basis of liability - 54 It may be that there are circumstances in which the identification of a physiological change, a disturbance of the normal physiological state or a psychiatric disorder may satisfy the definition of "ailment" (and therefore result in a positive answer to the first question) but the second question is answered "No". But if that is the position on the evidence, there will not be any relevant overlap between a "disease" and an "injury (other than a disease)" in the definition of "injury" in s 4(1) of the Act. It reflects the fact that there are marked differences between arising "out of" or "in the course of" (in para (b)) and "contributed to in a material degree" (for para (a)) in the definition of "injury". And it simply means that the employee was unable to satisfy the different level of employment connection required under para (a) of the definition of "injury" under the Act. 55 This construction of the definition of "injury" in s 4(1) of the Act does not "rob" the "disease" limb of utility. The "disease" limb of the definition remains an additional basis of liability. 56 The proper construction of the Act reflects the importance of the distinction drawn by the Act between "disease" and "injury (other than a disease)" in the definition of "injury" in s 4(1) of the Act and recognises that each creates a different basis for liability under the statutory scheme. [Footnotes omitted.] 101 As I stated earlier, [57] of the joint judgment was relied upon by counsel for Comcare to support a submission that a physiological or psychiatric change is necessary in order for there to be an "ailment" for the purposes of the "disease" limb of the defined term "injury" in s 4(1) - Not sufficient for an employee merely to feel unwell 57 The Full Court concluded that the inquiry demanded by the statutory definition of "injury" was "whether the person has experienced a physiological change or disturbance of the normal physiological state (physical or mental) that can be said to be an alteration from the functioning of a healthy body or mind" (emphasis added). To the extent that conclusion suggested that subjectively experienced symptoms, without an accompanying physiological or psychiatric change, are sufficient to provide a positive answer to the first or third questions set out above, that conclusion should be rejected. 102 The "first question" referred to in the last sentence of the above passage is the first question posed in [50] of the joint judgment, relating to whether there is a physical or mental ailment, disorder, defect or morbid condition for the purposes of the definition of "ailment". The "third question" is the question posed at [52] of the joint judgment, namely, "does the evidence demonstrate the existence of a physical or mental injury (in the primary sense of that word)?". The relevant paragraphs of the joint judgment are set out under [99] above. 103 Their Honours went on to hold at [67] that while the Tribunal had accepted that Mr May felt unwell, the "nature and incidents of the physiological [or psychiatric] change" suffered by Mr May were not established, with the result that there was no "injury" in the primary sense of the word. 104 It is reasonably clear from the joint judgment in MRCC v May that the requirement that there be a physiological change is applicable only to "injury (other than a disease)", and is not applicable to an "ailment". The main indications are, first, that the court was not concerned with a claim by Mr May to have suffered a "disease" that was contributed to in a material way by his employment, but a claim for an "injury (other than a disease)", and that it was a claim of the latter type that was the subject matter of the reasons in the joint judgment. This is reflected in the attention that is given in the reasons to the fact that "disease" and "injury (other than a disease)" are separate bases of liability, and that the Act "draws an important distinction between 'disease' and 'injury (other than a disease)'", and that "[e]ach limb deals with a separate basis for something being an 'injury'": see [59]. 105 The second indication is that in posing the first and second questions at [50], there is no reference to any requirement that there be a physiological change in order for there to be an "ailment". Rather, the second question that is posed is whether the employee's "state" was contributed to in a material degree by the employee's employment by the Commonwealth. This is consistent with the definition of "ailment" in s 4(1) of the Act, which includes a "disorder, defect or morbid condition". Those conditions are effects on an employee's body or mind which, if employment contributed in a material degree, would constitute injuries in respect of which there is a liability to pay compensation: see, Canute v Comcare [2006] HCA 47; 226 CLR 535 at [10] (Gummow A-CJ, Kirby, Callinan, Heydon and Crennan JJ). 106 The third indication is that the main focus of the judgment was to identify the characteristics of an "injury" in the primary sense. On that question, [52] is central. Their Honours expressly refrained from laying down an exhaustive judicial formulation, but gave the guidance that, generally, the question whether there was an injury will be determined by asking "whether the employee has suffered something that can be described as a sudden and ascertainable or dramatic physiological change or disturbance of the normal physiological state". I do not consider that Gageler J described an "injury" in materially different terms at [75] in stating - An injury, it has long been repeatedly explained, is some definite or distinct "physiological change" or "physiological disturbance" for the worse which, if not "sudden", is at least "identifiable". [Footnote omitted.] 107 At [76], Gageler J distinguished an "injury" involving a definite or distinct physiological change in the above sense from "any alteration from the functioning of a healthy mind or body". 108 The fourth indication is [54], which states that there may be circumstances in which the identification of a physiological change, a disturbance of the normal physiological state or a psychiatric disorder may satisfy the definition of "ailment". This picks up some of the language of [52], but shorn of "sudden and ascertainable or dramatic", which were held at [47] not to be necessary conditions of "injury" in its primary sense, but which were nonetheless relevant. I would therefore not understand [54] to venture into any sort of considered explanation of the defined term "ailment". Instead, I would understand [54] merely to make the point that a condition that is a candidate to be an "injury" in the primary sense may qualify as an "ailment", but would not constitute a "disease" if the relevant connecting condition is not satisfied, namely that the ailment or an aggravation was contributed to in a material degree by the employment. 109 The court's reasons at [54] form an important part of the context in which [57] is to be understood. Other contextual features are the facts that were found by the Tribunal and which were summarised in the joint judgment; the heading above [57]; and the immediately succeeding paragraphs. On the facts found by the Tribunal, Mr May had subjectively experienced symptoms that were unaccompanied by physiological or psychiatric change, where no diagnosis could be made, and which the joint judgment characterised by the heading above [57], and in [67], as a state where Mr May felt "unwell". All that the joint judgment is relevantly saying at [57] is that Mr May's condition of feeling unwell, where there had been no diagnosis, would not have resulted in an affirmative answer to the first question that was posed at [50]. Otherwise, the succeeding paragraphs of the joint judgment, and in particular [61]-[62], focus on "injury" in its primary sense as a component of the phrase "injury (other than a disease)". There was no discussion of the ambit of the defined term "ailment", or of any necessary characteristics of its components, as Mr May had made no such claim. 110 The statutory definition of "ailment" in s 4(1) of the SRC Act should be "approached on the basis that Parliament said what it meant and meant what it said": Owners of the ship "Sin Kobe Maru" v Empire Shipping Co Inc [1994] HCA 54; 181 CLR 404 at 420. The definition of "ailment" refers to "any physical or mental ailment, disorder, defect or morbid condition (whether of sudden onset or gradual development)". These are words of ordinary meaning. A requirement that an ailment be "physical or mental" corresponds to the elaboration of "injury (other than a disease)" in s 4(1) as being "a physical or mental injury" and should not be regarded as words of limitation. The key point which I would understand their Honours to identify by [57] of the joint judgment in MRCC v May is that even with an ailment, "there must be more than an assertion by an employee that he or she feels unwell": at [62]. Even then, I would say that in relation to "ailment" this statement would fall into the category of general guidance, and that the text of the Act has to be applied to the circumstances of individual cases as presented by the evidence, which will vary immensely. In the case of the onset of migraines or chronic headaches, it might readily be accepted by a trier of fact in a particular case that such an ailment is not the product of "a sudden and ascertainable or dramatic physiological change or disturbance of the normal physiological state": cf, MRCC v May at [52]. Whether that is so will depend upon the evidence. However, there is nothing in the definition of "ailment" that invites the application of these criteria, which have been developed to assist triers of fact in borderline cases to identify whether or not a condition is an "injury" in the primary sense. Further, to require that there be an "identifiable physiological change" as an element of an "ailment" would distort the defined term "ailment" by importing a characteristic that is the hallmark of an "injury" in the primary sense, thereby narrowing the distinction between them. 111 It follows that in deciding that the applicant had not suffered an ailment on the ground that no physiological change could be identified, the Tribunal misdirected itself. The errors commenced with the Tribunal's statement that it was common ground between the parties that no physiological change could be identified, when the applicant had made no such concession. Further, reading the Tribunal's reasons as a whole I am left with the impression that the Tribunal equated the identification of physiological change as requiring evidence in the form of objective pathology or test results. I referred at [52]-[54] above to the evidence given to the Tribunal by A/Prof Darveniza. The tenor of that evidence was that there was a physiological change, but there was no test such as an MRI scan which could detect the change, which was the usual position in relation to migraines, and that medical science could not explain the change. But as A/Prof Darveniza stated, "because someone can't describe it doesn't mean to say it doesn't exist". In evaluating whether there was a physiological change, which Comcare had argued was a necessary requirement, the Tribunal did not deal with this aspect of the evidence. On the assumption that demonstration of a physiological change was required, there was no exploration by the Tribunal of issues such as the "disordered neurotransmission" to which A/Prof Garrick had referred, the fact that (unlike MRCC v May) there were medical diagnoses of the applicant's condition and of its cause before the Tribunal, and of the evidence of A/Prof Darveniza about a new treatment that was potentially effective and appropriate in the case of the applicant to treat her migraines, namely monoclonal antibodies. However, to be clear, I do not consider that the identification of a physiological change in the applicant was required in order to engage the definition of "ailment" in the Act. 112 There will be many cases where a physical or mental ailment can be diagnosed by a medical practitioner based upon the employee's history, and upon studied instances of cause and effect without recourse to pathology or other diagnostic aids. That did not occur in MRCC v May, where the medical evidence that the Tribunal accepted was that there was a lack of any pathology consistent with Mr May's symptoms, and otherwise the absence of any medical diagnosis other than a "functional somatic disorder" which did not amount to an "injury" in its primary sense: see the joint judgment at [18] and [27]. The present case is different. As I have mentioned, the Tribunal made a finding at [66] of its reasons, based on its acceptance of the applicant's own evidence and the medical evidence that it accepted, that the applicant continued to suffer chronic daily headaches to which, on the balance of probabilities, her former employment still contributed to a material degree. As I have mentioned, it also found that there was an available new treatment that the applicant had not attempted. Paradoxically, it was the applicant's failure to attempt this treatment that led the Tribunal to find, on an alternative basis, that the applicant's impairment was not permanent. The Tribunal's finding of contribution to a material degree by the applicant's former employment is important, because it demonstrates that this was not a case of the applicant merely feeling unwell. On the evidence that the Tribunal accepted, the applicant suffered a condition that was the subject of a specialist medical diagnosis and to which her employment was a contributing cause. What the Tribunal should then have done was to consider whether, on the basis of those findings, the applicant had an "ailment", which amounted to a "disease", thereby amounting to an "injury" (as defined). By the application of the words of ordinary meaning within the definition of "ailment" in s 4(1) of the SRC Act to the Tribunal's primary findings at [66], there was only one conclusion that was reasonably and therefore lawfully open to the Tribunal, namely that the applicant had suffered an injury for the purposes of s 14 of the SRC Act, and that Comcare was therefore liable to pay her compensation under the Act in respect of that injury.

The calculation of normal weekly earnings 113 That brings me to what the applicant's application to the Tribunal was really about, which was to have the Tribunal review Comcare's calculation of her normal weekly earnings for the purposes of calculating weekly payments for which Comcare had accepted liability back in 2012. The Tribunal did not undertake that review, because it erroneously accepted the submissions put on behalf of Comcare, finding that the applicant had not suffered a compensable injury, and determined at [112] of its statement of reasons that it was unnecessary to consider the applicant's application. Instead, the Tribunal offered "in summary form [its] reasons for rejecting Comcare's submissions on the calculation of NWE in s 8". 114 The Tribunal's reasons in relation to the calculation of normal weekly earnings, albeit not operative reasons, were inadequate, misapprehended the issue that was to be determined on review, failed to address submissions that were put to the Tribunal by both parties, and misapplied the reasons for decision of Rares J and of the Full Court in the previous proceedings. Because the Tribunal failed to discharge its review function, the matter will have to be remitted to the Tribunal so that a review can be undertaken. I will state briefly my reasons for these conclusions. 115 As I mentioned earlier, prior to the onset of her injury the applicant had been engaged on terms that she would work a four day week, which amounted to 29.4 hours per week. However, part of the applicant's claim is that in "the relevant period" prior to the onset of her injury (see s 9 of the SRC Act), she was required to work well in excess of those hours, and that the additional work that she was required to perform contributed to a material degree to her injury. The ongoing dispute between the applicant and Comcare is whether her normal weekly earnings should be calculated on the basis of 29.4 hours per week, or on the basis of a greater number of hours reflecting the hours that the applicant was actually working in the two week period immediately prior to the onset of her injury. That dispute has been alive since Comcare's original decision dated 14 August 2013 which was affirmed upon internal reconsideration on 23 December 2013, and has not yet been resolved. 116 On 9 December 2015, the Tribunal affirmed Comcare's reviewable decision of 23 December 2013: Wuth and Comcare [2015] AATA 947. In affirming Comcare's decision the Tribunal made a factual finding at [22] that during the relevant period prior to the onset of her injury in February 2007, the applicant was working more than 36.75 hours per week. The Tribunal found that consistent with the terms of her Australian Workplace Agreement, the applicant was credited with some time off in lieu (TOIL) in recognition of the additional hours that she worked. The Tribunal affirmed Comcare's reviewable decision, holding that normal weekly earnings should be calculated by reference to the applicant's agreed hours, namely 29.4 hours per week. 117 On the applicant's cross appeal from the Tribunal's decision of 9 December 2015, Rares J held that the Tribunal had been in error in failing to apply its finding that the applicant had worked more than 36.75 hours per week in the relevant period to the calculation of normal weekly earnings as required by the formula set out in s 8(1) of the SRC Act: Comcare v Wuth [2017] FCA 433; 72 AAR 84 at [13]-[17]. In consequence, Rares J made the orders set out at [43] above from which Comcare appealed to the Full Court. The appeal from those orders was dismissed, although other grounds of Comcare's appeal which are not now relevant were allowed: Comcare v Wuth (No 2) [2018] FCAFC 60. The Full Court held that Rares J's decision in relation to the calculation of normal weekly earnings was correct: [15]-[21] (Flick J), [78]-[86] (Perry J), Siopis J at [1] agreeing with both. 118 By its decisions of 11 May 2018 and 27 July 2018 to which I referred at [47] above, Comcare then invoked s 8(5) of the SRC Act, having not previously placed reliance upon it. Section 8(5) is engaged where "because of the shortness of the relevant period, the normal weekly earnings as calculated in relation to the relevant period … would not fairly represent the weekly rate at which the employee was being paid". A threshold issue is whether upon an evaluation of the facts of the applicant's claim s 8(5) is engaged. When engaged, s 8(5) authorises Comcare to calculate normal weekly earnings by reference to "such other period as Comcare considers reasonable" for the purposes of arriving at an amount that fairly represents the weekly rate at which the employee was being paid. 119 The applicant was entitled to have the Tribunal review Comcare's decision that s 8(5) was engaged, and its decision that normal weekly earnings should be calculated in the amount that Comcare arrived at. The Tribunal's obligation was to arrive at the correct or preferable decision after hearing from the parties. Both parties made considered submissions to the Tribunal concerning the merits of the matter. The Tribunal did not engage with the parties' submissions. Instead, the Tribunal's conclusion at [118] which I have set out under [64] above sought by a process of impermissible speculation to extrapolate the reasons of Rares J and the Full Court. This was in error because, first, the application of s 8(5) was not even before the courts in the earlier appeal, and secondly the courts were concerned with the questions of law that were raised, and not with the merits. In summary, it was in error for the Tribunal to ask itself what the courts might have thought about the merits of Comcare's application of s 8(5), and it thereby failed to discharge its statutory function to review the decision. 120 Counsel for Comcare submitted that on the evidence before the Tribunal Comcare's decision had to be affirmed, and the appeal to this court should be dismissed in any event. I do not accept this submission. Sub-section 8(5) requires the making of value judgments in this matter, which were for the Tribunal to consider having regard to the parties' submissions, and which it failed to address.

Conclusions 121 The appeal should be allowed. The decision of the Tribunal in matter 2018/4238 should be set aside and the matter should be remitted for redetermination in accordance with these reasons and otherwise according to law. The question of allocation will be a matter for the President or Acting President of the Tribunal. 122 As to costs, Comcare should pay the applicant's the costs of this appeal. The parties' costs to date of matter 2018/4238 before the Tribunal should be reserved to the Tribunal conducting the redetermination upon the premise that in exercising its discretion as to costs under s 67 of the SRC Act, subject to any special considerations and the submissions of the parties to the Tribunal, the Tribunal might determine that the costs of that matter should follow the event. Nothing said here is intended to guide the Tribunal's discretion, which is a matter for the Tribunal to consider after hearing the parties.

Final remarks 123 In Ball v William Hunt & Sons Ltd [1912] AC 496 at 500, Lord Macnaghten described the Workmen's Compensation Act 1906 (Eng) as "the workmen's charter", thereby pointing to the beneficial character of the legislation. Under the SRC Act, Comcare is conferred with functions which are consistent with the view that the Act is beneficial legislation. Under s 69(a), Comcare is to "make determinations accurately and quickly", and in performing that function s 72(a) mandates that Comcare - shall be guided by equity, good conscience and the substantial merits of the case, without regard to technicalities; 124 These exhortations are important to the proper and beneficial functioning of the compensation scheme. 125 It is an unsatisfactory situation that almost 12 years after the applicant first made her claim for compensation, the quantum of her weekly payments has yet to be finally resolved. There have been many contributing causes, not the least of which are the two occasions on which the Tribunal has made decisions that have been found by this court to be attended with error. 126 The issue that now remains in dispute is simple, narrow, and ought to be capable of being determined by the Tribunal without any further evidence, and upon the basis of concise and focussed submissions of the parties that avoid false issues and technicalities, and which squarely address the merits. I certify that the preceding one-hundred and twenty-two (122) numbered paragraphs are a true copy of the Reasons for Judgment of the Honourable Justice Wheelahan.

SNADEN J: 127 I have had the privilege of reviewing a draft of Wheelahan's J reasons for judgment in this matter. I gratefully endorse the orders that his Honour proposes and agree with the reasons for which he proposes them. I certify that the preceding one (1) numbered paragraph is a true copy of the Reasons for Judgment of the Honourable Justices Snaden.