Comcare v Wuth

BETWEEN: COMCARE Applicant/Cross-respondent

AND: NICOLE WUTH Respondent/Cross-applicant

JUDGE: RARES J DATE OF ORDER: 27 APRIL 2017

1. The appeal be dismissed.
2. The cross-appeal be allowed.
3. Decision 1 made by the Administrative Appeals Tribunal in application 2014/0673 to affirm Comcare's decision on 23 December 2013 be set aside and the following decisions be substituted in lieu thereof:
4. 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.
5. Comcare pay the applicant's costs in Applications 2014/0673 and 2014/4007 pursuant to s 67(8) of the Safety, Rehabilitation and Compensation Act 1988 (Cth).
6. The applicant/cross-respondent pay the respondent/cross-applicant's costs of the appeal and cross-appeal. Note: Entry of orders is dealt with in Rule 39.32 of the Federal Court Rules 2011.

RARES J: 1 Comcare has appealed to the Court under s 44 of the Administrative Appeals Tribunal Act 1975 (Cth) (the AAT Act) from a decision of the Administrative Appeals Tribunal that Comcare is liable to pay Nicole Wuth compensation, first, under s 24 of the Safety, Rehabilitation and Compensation Act 1988 (Cth) (the SRC Act) in respect of her chronic migrainous headaches, secondly, under s 27 for non-economic loss and, thirdly, on the basis that her degree of permanent impairment is 14%. Ms Wuth cross-appealed on the basis that she asserted the Tribunal erred in construing s 8 of the SRC Act in arriving at its calculation of her normal weekly earnings (NWE) by using 29.4 hours (or four days work) rather than 36.75 hours (or five days) by reference to which Comcare had to pay her compensation under s 19 of the SRC Act.

Background 2 In February 2006, Ms Wuth was an executive level 1 in the Department of Health and Ageing. Her employment was on a full-time basis. She then saw her general practitioner, Dr Ian Brown, who treated her for symptoms consistent with chronic fatigue syndrome. On his advice, in mid-2006, she reduced her working hours from five to four days a week by using personal leave for the day not worked and so remained a full-time employee. In November 2006, Ms Wuth accepted a voluntary transfer, under s 26 of the Public Service Act 1999 (Cth), to the then Department of Finance and Administration at the same level of employment. She took up her new position with the Department on 27 November 2006 and thereafter, as the Tribunal found, worked long hours. 3 By February 2007, Ms Wuth developed a disease that different medical practitioners described as "vertiginous common migraines", "simple chronic headache of a migraine type" and "chronic" and "persisting post inflammatory headache". She went on leave on about 19 May 2008. In November 2008, Ms Wuth was deemed unfit for work and her leave was extended. On 27 May 2010, the Department terminated Ms Wuth's employment on the ground of her invalidity. 4 On 29 April 2010, Ms Wuth made a claim for workers' compensation for "entrenched chronic daily headaches arising from an exacerbation of post-viral fatigue". After Comcare had disallowed her claim, the Tribunal found on 14 September 2012 that: Ms Wuth suffered chronic daily headache, which was a disease that was significantly contributed to by her employment with the Department, with a deemed date of injury of 27 February 2007; Comcare was liable to pay compensation to Ms Wuth under s 14 of the SRC Act in respect of chronic daily headache; and Comcare was not liable to pay compensation to Ms Wuth in respect of post-viral fatigue. 5 The Tribunal noted that the parties had agreed that Ms Wuth's chronic daily headache may have caused symptoms of tiredness or fatigue. 6 On 14 August 2013, Comcare made a determination that Ms Wuth's normal weekly earnings for the purposes of s 8 of the SRC Act should be based on 29.4 hours (for four days per week). On 23 December 2013, Comcare affirmed that determination and dismissed Ms Wuth's request for its reconsideration. On 5 February 2014, Ms Wuth applied to the Tribunal to review that decision under s 64 of the SRC Act. 7 On 19 February 2014, Ms Wuth made a claim to Comcare for compensation for permanent impairment and non-economic loss under ss 24 and 27 of the SRC Act. On 21 March 2014, Comcare disallowed that claim on the ground that it was not liable to pay compensation, first, under s 24 for permanent impairment in respect of "chronic daily headache" and, secondly, as a consequence, for non-economic loss under s 27. On 3 July 2014, Ms Wuth applied to the Tribunal to review that decision under s 64.

The legislative scheme 8 Relevantly, the SRC Act provided as follows: 4 Interpretation (1) In this Act, unless the contrary intention appears: … impairment means the loss, the loss of the use, or the damage or malfunction, of any part of the body or of any bodily system or function or part of such system or function. … permanent means likely to continue indefinitely. … relevant period means the period calculated under section 9. … 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. 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. (2) Subject to subsection (3), if, during the period referred to in subsection (1), the minimum amount per week payable to an employee in respect of his or her employment by the Commonwealth or a licensed corporation was varied as a result of: (a) the operation of a law of the Commonwealth or of a State or Territory; or (b) the making, alteration or operation of an award, order, determination or industrial agreement, or the doing of any other act or thing, under such a law; any part of that period that occurred before the variation, or last variation, took place shall be disregarded for the purposes of calculating the relevant period. … (4) If, during any part of the period calculated under the preceding subsections, the employee's earnings were reduced, or the employee did not receive any earnings, because of absence from his or her employment for any reason, that part of that period shall be disregarded for the purposes of calculating the relevant period. (emphasis added) 9 Relevantly, s 24 made provision for Comcare's liability to pay compensation in respect of an injury that resulted in permanent impairment and for it to assess the degree of that impairment by making a determination, in accordance with s 24(5), "under the provisions of the approved Guide", being the version in force of the "Guide to the Assessment of the Degree of Permanent Impairment" approved by the Minister pursuant to s 28. Comcare had to express the degree of permanent impairment as a percentage (s 24(6)) and, where it determined that the degree was less than 10%, s 24(7)(b) provided that it was not liable to pay compensation under s 24. The approved Guide is a legislative instrument by force of s 28(3A) and so the rules of statutory construction apply to its provisions. Importantly, s 28 provided: 28 Approved Guide (1) Comcare may, from time to time, prepare a written document, to be called the "Guide to the Assessment of the Degree of Permanent Impairment", setting out: (a) criteria by reference to which the degree of the permanent impairment of an employee resulting from an injury shall be determined; (c) methods by which the degree of permanent impairment … as determined under those criteria, shall be expressed as a percentage. …. (4) Where … the Administrative Appeals Tribunal is required to assess or re-assess, or review the assessment or re-assessment of, the degree of permanent impairment of an employee resulting from an injury, … the provisions of the approved Guide are binding on … the Administrative Appeals Tribunal, … in the carrying out of that assessment, re-assessment or review, and the assessment, re-assessment or review shall be made under the relevant provisions of the approved Guide. (5) The percentage of permanent impairment … suffered by an employee as a result of an injury ascertained under the methods referred to in paragraph (1)(c) may be 0%. (6) In preparing criteria for the purposes of paragraphs (1)(a) and (b), or in varying those criteria, Comcare shall have regard to medical opinion concerning the nature and effect (including possible effect) of the injury and the extent (if any) to which impairment resulting from the injury, … may reasonably be capable of being reduced or removed. (emphasis added) 10 It will be convenient to deal with the facts and issues on Ms Wuth's cross-appeal first in these reasons, before turning to consider the facts and issues on Comcare's appeal.

The cross-appeal - What were Ms Wuth's normal hours of work? 11 The Tribunal found as a fact that during the two week period immediately before the date of her injury (namely 27 February 2007), "Ms Wuth was working more than 36.75 hours a week - that is, more than a full time workload". Yet it decided: 35. Ms Wuth's normal hours should be determined under s 8(1) having regard to her agreed hours only, and not the extra hours that she worked beyond her agreed hours during the relevant period. Comcare was correct to calculate her NWE on the basis that she worked an average of 29.4 hours (four days) a week during the relevant period. (emphasis added)

Comcare's submissions 12 Comcare argued that Ms Wuth had not been able to demonstrate any legal error in the Tribunal's finding that her normal weekly earnings in the relevant period should be calculated using the value of 29.4 hours as her average number of hours worked in the relevant period for the purposes of the item NH in the formula in s 8(1). It contended that those were her agreed hours, under her contract, and represented the only hours which the Tribunal could use. It submitted that this finding was open to the Tribunal on all of the evidence relating to Ms Wuth's employment terms and her agreement with the Department in November 2006 that she would work only four days or 29.4 hours per week, which had been based on medical advice in light of her condition. Comcare also relied on the fact that Ms Wuth was only paid for 29.4 hours per week in the relevant period of two weeks before the date of her injury. It also argued that the reference in s 8(1) to "the average number of hours worked in each week by the employee in his or her employment" had to be read as including the word "paid" before "hours": i.e. the average number of paid hours worked. It contended that using any greater number of hours in applying the formula in s 8(1) would be contrary to the legislative intention, and it called in aid the decision of the Full Court in Comcare v Nicolas (2014) 225 FCR 369 at 376 [42].

Consideration 13 The ultimate finding that the Tribunal made was that the value of NH in the formula in s 8(1) used to calculate Ms Wuth's normal weekly earnings was 29.4 hours. I am of opinion that this finding was not a finding of fact that was made under ss 8(1) and 9. That is because, the Tribunal's ultimate finding was not based on the application of the actual facts that the Tribunal had found in the first sentence of [35] of its reasons, namely that Ms Wuth actually worked "extra hours", being its earlier finding at [22] of its reasons, during "the relevant period". The relevant period, as s 9(1) provided, was "the latest period of 2 weeks before the date of the injury during which the employee was continuously employed", and the Tribunal had found that she "was working more than 36.75 hours a week". 14 There was no basis in the Act on which the Tribunal could ignore that Ms Wuth actually worked more than 36.75 hours in each of the two weeks immediately before 27 February 2007, as it did in [35], by "having regard to her agreed hours only" and using 29.4 hours a week instead in performing that statutory calculation in s 8(1). 15 The Tribunal had to make the calculation of normal weekly earnings by following the steps mandated in the Act. The Tribunal noted that the parties had agreed that s 8(10) of the SRC Act had no application in the review. 16 Normal weekly earnings meant, as s 4(1) provided, "the normal weekly earnings of an employee calculated under section 8". That calculation depended on finding the value to be used for NH in the formula in s 8(1), namely "the average number of hours worked in each week by the employee in his or her employment during the relevant period", where s 9(1) provided the only relevant criterion (unless one of the exceptions in s 9(2), (3) or (4) applied) for ascertaining "the relevant period". The Tribunal did not find, and the parties did not argue, that any of s 9(2), (3) or (4) applied to displace the use of the two week period immediately before the date of the injury required by s 9(1) as "the relevant period" for the purpose of s 8(1). The calculation required by s 8(1) did not use, or require the use of, the agreed hours of employment. Rather, the calculation required the use of the actual hours "worked by the employee in … her employment" in each of the two weeks immediately before the date of the injury. 17 The Tribunal, having found that Ms Wuth worked more than 36.75 hours a week in her job in the relevant period, had to use that finding in making its calculation of her normal weekly earnings under s 8(1). The Tribunal made an error of law by substituting what it conceived to be a different contractual rate, that ignored the statutory criterion of actual hours worked in the relevant period. It applied a criterion that disregarded the statutory text in ss 8(1) and 9. 18 Comcare's argument that the Tribunal made a mere finding of fact when determining that Ms Wuth's normal weekly earnings should be calculated "having regard to her agreed hours only", namely, "29.4 hours … a week during the relevant period", must also be rejected. First, the Tribunal found a different and inconsistent fact, namely that she worked more than 36.75 hours a week in the relevant period and, secondly, it substituted for that finding of actual fact an hypothesis for which there was no statutory or factual basis. Indeed, the scheme of ss 8 and 9 recognised that the calculation of normal weekly earnings sometimes would need to be made on facts that were different to the "normal" or "agreed" terms of an employee's employment. Thus, s 8(2) required the inclusion of overtime that an employee "is required to work … on a regular basis" as part of the calculation of normal weekly earnings, and s 8(3) required the inclusion of any earnings of a part-time employee from other employment during the relevant period in the calculation. 19 The Tribunal sought to justify (at [26]-[27] of its reasons) its use of the "agreed" 29.4 hours a week by reference to some of what Edmonds, Buchanan and Flick JJ had said in Nicolas 225 FCR at 376 [42]. Their Honours said (and I note that the Tribunal did not include in its quotation the final two sentences set out below): In that period Ms Nicolas worked all of the hours expected of her for a two-week period. Those hours (and the rate of pay applied to them) gave "the weekly rate at which the employee was being paid in respect of … her employment before the injury". The importance of that factual circumstance was not altered by the expectation that the hours might increase in the months to come. The task of the AAT was to examine whether the two-week period before the injury on 13 May 2011 was fairly representative of normal weekly earnings pre-injury, not to assess whether those earnings might be expected to increase in the future. Furthermore, if any adjustment was to be made, by selecting a different period, it was necessary to select a period which furnished actual hours and actual rates of pay. Once the period before December 2008 is put aside, there was no other period reasonably available. (bold and italic emphasis added) 20 The Tribunal appears to have taken the sentence I have italicised in their Honours' reasons as justifying what it said at [27] of its reasons immediately after its quotation of most of the above passage, namely: It follows from the Full Court's decision in Nicolas, that I must apply s 8 in this review without regard to the possibility - even the probability - that Ms Wuth would have become a full-time employee of the Department if she had not been injured. (emphasis added) 21 That result did not follow from their Honours' decision. That is because what the Full Court decided in Nicolas 225 FCR 369, in particular at 376 [42], concerned the construction of different provisions, namely, s 8(4) and (5), that had no relevance to Ms Wuth's situation under s 8(1). The Full Court decided that the expression in s 8(5), whence the words in quotation marks have their source in the second sentence of the passage I have set out in [19] above, set the Tribunal a task of deciding, when s 8(5) applied, whether the two week period immediately before the date of the injury was fairly representative of normal weekly earnings pre-injury. That issue could only arise if the precondition in s 8(5) applied (which it did not in Ms Wuth's case), namely: 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, … (emphasis added) 22 The Tribunal also reasoned that Ms Wuth had agreed with the Department that she would work part-time four days (or 29.4 hours) a week "with an expectation (shared with the Branch Manager) that she would eventually work on a full-time basis". It found that she had "continued to work on a part-time basis up until, and during, the relevant period". 23 There is no dispute that Ms Wuth was only paid for 29.4 hours a week, including in the relevant period. The Department's offer of permanent reassignment, that Ms Wuth accepted on 14 November 2006, provided that she would have an annual remuneration package that would be "pro-rated based on part time hours of 29.4 hours per week". The letter of offer provided that its terms would be replaced subsequently by those in an Australian Workplace Agreement. In the event, she became entitled to be granted time off in lieu or "TOIL" "to recognise short term additional hours worked" under cl 2.3 of the Australian Workplace Agreement that she made with the Department dated 18 June 2007. 24 It appears that that entitlement to TOIL applied in respect of the extra hours (above 29.4 hours per week) that Ms Wuth worked during the relevant period and she gave evidence that she did not expect to be paid for those extra hours but rather expected to, and did, receive TOIL. 25 However that may be, the only applicable provisions in the SRC Act on which to calculate Ms Wuth's normal weekly earnings were those in ss 8(1) and 9(1). Those provisions referred not to the hours in the relevant period for which she was paid in money, but to the hours that she actually worked. The fact that Ms Wuth was content to take consideration for her labour in the form of leave (time off in lieu) for the additional hours that she worked did not mean that the statutory calculation of her normal weekly earnings could be performed by only using the 29.4 hours for which she received monetary consideration particularly in circumstances where she also received consideration in the form of TOIL. 26 The NH figure in s 8(1) applies to facts, not hypotheses. The only relevant fact that the Tribunal needed in order to ascertain the NH value in s 8(1) was the actual average number of, namely, more than 36.75, hours a week that Ms Wuth worked in the relevant two week period. In her notice of cross-appeal Ms Wuth only sought a finding that the NH figure be 36.75 hours per week based on the Tribunal's finding that in fact she worked in excess of that time during each of the two weeks in the relevant period. Accordingly, that figure should be used as the NH value in calculating her normal weekly earnings under s 8(1).

Conclusion on cross-appeal 27 For these reasons, I am of opinion that the Tribunal erred in failing to use 36.75 hours as the actual average number of hours worked to calculate Ms Wuth's normal weekly earnings in accordance with s 8(1). The cross-appeal must be allowed with costs.

Introduction 28 The issues in Comcare's appeal centre principally around its contentions that, first, the Tribunal misconstrued or misapplied Ch 18 of the American Medical Association's Guides to the Evaluation of Permanent Impairment (5th ed; 2001) (the AMA Guides) (as corrected in errata published in March 2002 (the 2002 errata)), the provisions of which applied to assessment of impairment in cases of migraine or tension headaches and, secondly, the Tribunal denied Comcare procedural fairness by determining for itself, using its own inexpert "clinical judgment", that Ms Wuth's degree of permanent impairment under s 24(6) of the Act was 14% after it had found that Ch 18 of the AMA Guides did not assign a percentage rating of impairment. 29 I will set out the grounds of Comcare's appeal, then, the relevant parts of the approved Guide and the AMA Guides (which, as will become apparent, are not easy to understand), before summarising the Tribunal's reasoning and Comcare's submissions. 30 Comcare contended in the grounds in its notice of appeal that the Tribunal had: (1) misconstrued Ch 18 of the AMA Guides by concluding that Ch 18 did not provide impairment ratings for Ms Wuth's chronic migrainous headaches condition; (2) misconstrued the "clinical judgment" impairment evaluation method in Section 1.5, pages 10-11, of the AMA Guides by concluding that Ms Wuth had an "unlisted condition" that fell to be evaluated under the clinical judgment impairment evaluation; (3) misapplied that evaluation by undertaking its own evaluation when there was no evidence from a physician on which to make such an evaluation; (4) denied Comcare procedural fairness because Comcare was not put on notice, and had no opportunity to make submissions in the event, that the Tribunal might attempt to undertake its own clinical judgment evaluation or might find that, using "clinical judgment", Ms Wuth's level of impairment was 14%. 31 In the Tribunal, the parties tendered numerous medical reports, from not only Ms Wuth's treating neurologist Associate Professor Raymond Garrick, but also others prepared for use as expert evidence in the hearing, including by Associate Professor White (tendered by Ms Wuth) and Dr Seneviratne (tendered by Comcare). 32 At the outset, it is important to bear in mind the following matters about which the Tribunal made unchallenged findings: Ms Wuth suffered from chronic migrainous headaches caused by a viral infection in early 2006; those headaches were aggravated during her employment with the Department in late 2006 and, especially, in early 2007; her employment with the Department contributed to that aggravation to a significant degree; the pain from those headaches caused a loss of function; Ms Wuth had undertaken all reasonable rehabilitative treatment for those headaches; the headaches were likely to continue indefinitely; the aggravation of Ms Wuth's chronic migrainous headaches was a disease, and therefore an injury, within the meaning of s 5A(1) of the SRC Act; that injury had resulted in an impairment that was permanent, so that Comcare was liable, by force of, but subject to, s 24 of the SRC Act, to pay Ms Wuth compensation in respect of that injury.

The approved Guide and the AMA Guides 33 The approved Guide for the purposes of s 28 of the SRC Act was Edition 2.1. Part 1 of the approved Guide dealt with claims for permanent impairment, other than claims under the SRC Act by members of the Australian Defence Force. The latter class of claims were the subject of Pt 2. Nothing in Pt 1 of the approved Guide dealt directly with migraines, headaches or intermittent conditions. However, as the Tribunal noted, section 13 in Pt 2 dealt with those topics for claims to compensation by members of the Defence Force under the heading "Miscellaneous", relevantly, in the portions of the table set out below (although the table continued with percentages up to 75-95% that were appropriate for more severe conditions), where the percentage of impairment corresponded, as in the extract below, to the frequency of the occurrences of the episodes. Table 13.1 provided (at 261): 13. Miscellaneous Table 13.1: Intermittent conditions (Percentage whole person impairment) For use in the assessment of disorders of the haemopoietic system such as anaemia, polycythaemia, leukocyte and platelet disorders and intermittent disorders such as asthma, migraine, tension headache, epilepsy etc. Principles: Determine the frequency, duration and severity of attacks with reference to the degree of interference with activities of daily living. % Description of level of impairment 0 Episodes may be of any frequency but do not interfere with activities of daily living or are readily prevented or reversed by appropriate medication or treatment. 10 Episodes occur 12 or more times a year and cause minor interference with activities of daily living or episodes occur less frequently and cause interference with all activities of daily living other than self care. 20 Episodes occur up to 25 percent of the time and cause significant interference with most activities of daily living other than self care.

(emphasis added) 34 It was common ground that Ms Wuth's impairment could not be assessed under Pt 1 of the approved Guide. In that situation, the approved Guide (at 13) provided, under the heading "Principles of Assessment": 12. Exceptions to use of Part 1 of this guide In the event that an employee's impairment is of a kind that cannot be assessed in accordance with the provisions of Part 1 of this guide, the assessment is to be made under [the AMA Guides]. An assessment is not to be made using the [AMA Guides] for: … • chronic pain conditions, except in the case of migraine or tension headaches. … (emphasis added) 35 The AMA Guides dealt with pain in Ch 18. In [18.2], headed "Overview of Pain", the authors noted that headache was a common disabling condition for which impairment had to be assessed primarily on the basis of the individual's reports of pain rather than on tissue pathology or anatomic abnormality. The reason, the authors explained, was "straightforward: in the majority of cases there is no demonstrable tissue pathology" (AMA Guides at 566). 36 Crucially, the AMA Guides explained in respect of Ch 18 (AMA Guides at 570): Third, this chapter assesses pain qualitatively. Because percentages for pain-related impairment have not been used and tested on a widespread basis, as have other impairment ratings used in the [AMA] Guides, it was decided that impairment ratings for pain disorders would not be expressed as percentages of whole person impairment. Future scientific evidence may emerge that will enable a more quantifiable approach to be adopted. Nevertheless, the value of a qualitative assessment is that any identification of a significant pain component warrants additional consideration when interpreting impairment ratings used for allocation of medical resources, work placement, or financial compensation. (emphasis added) 37 Next, [18.3a] (at 570) referred to situations in which the organ and body impairment rating system did not adequately address impairment, including where there are well-established pain syndromes without significant, identifiable organ dysfunction to explain the pain. The authors said that individuals with well-established pain syndromes, such as those listed in Table 18-1 that included "Headache (most)", "can be evaluated on the basis of concepts elaborated in this chapter". I should interpolate here that, in Ch 18, there is a difference between an "evaluation" and a quantitative percentage rating. 38 The AMA Guides then discussed in [18.3b] (at 571-572) when Ch 18 should not be used to rate pain-related impairment, namely, when a condition is adequately rated in other chapters, the individual to be assessed had low credibility or the pain syndrome was ambiguous or (diagnostically) controversial. The authors said that, for the purposes of Ch 18, ambiguous or controversial pain syndromes were "considered unratable" (at 571). The authors said that an examining physician could identify an ambiguous or controversial syndrome by a negative answer to any of the following three questions (in which case the individual's pain-related impairment would be unrateable under Ch 18), namely (AMA Guides at 572): 1. Do the individual's symptoms and/or physical findings match any known medical condition? 2. Is the individual's presentation typical of the diagnosed condition? 3. Is the diagnosed condition one that is widely accepted by physicians as having a well-defined pathophysiologic basis? 39 If the examining physician answered each question in the affirmative, the authors said that he or she should consider the individual's pain-related impairment to be rateable. However, the AMA Guides required the examining physician to use the assessment protocol in [18.3d] (at 572) in the case of both rateable and unrateable pain. The authors said that: when a physician judges pain-related impairment to be unratable, he or she is simply asserting an inability to determine how the activity restrictions reported by an individual are linked to a disease or injury. The decision regarding how to construe these reports must therefore be administrative, not medical. ([18.3b] at 572) (emphasis added) 40 The AMA Guides then discussed administrative issues associated with pain-related impairment in [18.3c] (at 572-573). The authors said that Ch 18 divided apparent pain-related impairment into three distinct categories, namely first, impairment rateable on the basis of the conventional rating system used elsewhere in the AMA Guides, secondly, pain-related impairment rateable according to concepts in Ch 18 and thirdly, pain-related impairment that was unrateable according to the concepts in Ch 18. The authors gave two reasons why those distinctions were crucial, namely, first, there are different legal criteria in different jurisdictions on which benefits are payable. They stated that when a pain-related impairment is unrateable, its effect can be described in accordance with the protocol in [18.3d]. The AMA Guides elaborated on this reason in [18.3c] (at 572), saying: The system described here distinguishes between an impairment rating using the organ system approach and impairment awarded on the basis of pain. This distinction permits administrative agencies to count "conventional" impairment ratings and pain-related impairment ratings on an equal footing, to discount pain-related impairment ratings, or to disregard them entirely. Similarly, the present system identifies individuals with unratable pain-related impairment so that administrative agencies can make informed decisions about whether or not to compensate these individuals. (emphasis added) 41 It then continued with the second reason for making the distinctions in Ch 18, namely (at 573): Second, the distinction between ratable and unratable pain-related impairment embodies a key premise of this chapter: physicians do not currently possess reliable, valid techniques for assessing impairment associated with pain in all clinical settings. It is then more appropriate for the examining physician to describe the individual's pain-related impairment as unratable than to give a rating that cannot be supported by either scientific evidence or consensus. (emphasis added) 42 Crucially, [18.3d] (at 573, as corrected in the 2002 errata) was headed "How to Rate Pain-Related Impairment: Overview" and set out a protocol, that relevantly read as follows: The system described in this chapter relies largely on self-reports by individuals. Thus, it differs significantly from the conventional rating system, which relies primarily on objective indices of organ dysfunction or failure. The present system assesses pain intensity, emotional distress related to pain, and ADL [activities of daily living] deficits secondary to pain. ADL deficits are given the greatest weight. An individual's pain-related impairment evaluation should be aborted if his or her behavior during the evaluation raises significant issues of credibility. If an individual has clinical findings atypical of a well-accepted medical condition, or is diagnosed with a condition that is vague or controversial, his or her pain-related impairment evaluation should be completed, but the results of the evaluation must be interpreted differently. Specifically, an examiner should characterize the resulting pain-related impairment as unratable, and should not award quantitative impairment. A detailed protocol for assessing pain-related impairment is described below and outlined in Figure 18-1. I. Evaluate the individual according to the body part or organ rating system (ie. the conventional rating system), and determine an impairment percentage. During the evaluation, the examiner should informally assess pain-related impairment. II. If the body system impairment rating appears to adequately encompass the pain experienced by the individual due to his or her medical condition, his or her impairment rating is as indicated by the body system impairment rating. III. If the individual appears to have pain-related impairment that has increased the burden of his or her condition slightly, proceed to Step VI. IV. If the individual appears to have pain-related impairment that has increased the burden of his or her condition substantially, perform a formal pain-related impairment assessment (Step V). Then proceed to Step VI. V. In a formal pain-related impairment assessment, the examiner administers and scores the inventory shown in Table 18-4 and provides quantitative ratings of an individual's pain behavior and credibility. The examiner then calculates the individual's total pain-related impairment as shown in Table 18-6, and determines the individual's pain-related impairment class as shown in Table 18-7. VI. Determine whether the individual's pain-related impairment is ratable or unratable. VII. If pain-related impairment is ratable, the examiner may award quantitative pain-related impairment of up to 3% and should (when appropriate) also designate the qualitative pain-related impairment class that best characterizes the individual's condition. VIII. If pain-related impairment is unratable, the examiner should not award quantitative pain-related impairment but should (when appropriate) designate the pain-related impairment class that best characterizes the individual's condition. (italics in original, emphasis added) 43 The protocol in [18.3d] recognised that a prima facie rateable pain-related impairment (having regard to the questions at 572, set out at [38] above) can, when assessed formally under Table 18-4, be in fact unrateable, as Steps VI and VIII expressly contemplated. Step VII gave the examiner a discretion, but not an obligation, where appropriate, to assign an additional quantitative measure of up to 3% as well as to clarify the qualitative degree of pain-related impairment. Step VIII required just classification of the qualitative rating of pain-related impairment. 44 Next, [18.5] (at 584, as corrected in the 2002 errata) emphasised that the examiner had an option or discretion to rate (under [18.5(5)]) or to decide that the pain was unrateable quantitatively but was nonetheless classifiable by a qualitative rating (under [18.5(6)]). It prescribed that the assessor follow the six steps in Table 18-6 to calculate a total pain-related impairment score so as to arrive at one of the four categories, classes or ratings of qualitative impairment (mild, moderate, moderately severe or severe) described in Table 18-3. The examiner had to then review the material in [18.3a] and [18.3b] to determine whether the pain-related impairment is rateable or unrateable ([18.5(3d-e)-(4)] and [18.5(5) and (6)] at 584, as corrected in the 2002 errata): 5. If an individual has ratable pain-related impairment, determine his or her final impairment rating as follows: a. If an individual's conventional impairment rating adequately encompasses the burden of his or her condition, the individual should not receive any additional pain-related impairment. b. If pain-related impairment increases the individual's burden of illness slightly beyond that indicated by his or her conventional impairment rating, award the conventional impairment and combine this with discretionary quantitative pain-related impairment of 1, 2%, or 3%. c. If pain-related impairment increases the individual's burden of illness substantially beyond that indicated by his or her conventional impairment rating, award the conventional impairment and combine this with discretionary quantitative pain-related impairment of 3%. Also, indicate the individual's qualitative pain-related class. 6. If an individual has unratable pain-related impairment, determine his or her final impairment rating as follows: a. If an individual's conventional impairment rating adequately encompasses the burden of his or her condition, or if it increases the burden of illness only slightly, the individual should not receive any additional pain-related impairment. b. If pain-related impairment increases the individual's burden of illness substantially beyond that indicated by his or her conventional impairment rating, award the conventional impairment rating and indicate the individual's qualitative pain-related impairment class. (italic emphasis in original; bold emphasis added) 45 The AMA Guides gave several case examples in [18.9]. Example 18-1 (at 586-587, as corrected in the 2002 errata) concerned a 28-year-old woman who was otherwise healthy but experienced approximately 20 severe migraine headache events per year. The headaches began at night, reached maximum intensity within two to three hours and, untreated, lasted 8 to 12 hours. The woman was "able to perform all ADL [activities of daily living], having some difficulties only during the [migraine] headache episodes". The example then concluded (at 586-587, as corrected in the 2002 errata): Impairment Rating: Based on the procedures described in Tables 18-4 through 18-7, the individual's total pain-related impairment score is 20. She is therefore classified as having mild pain-related impairment. The examiner has the option of awarding 1%, 2%, or 3% quantitative impairment to reflect this. There is no ratable impairment based on organ or body part dysfunction. Comment: During her attacks, this woman is completely impaired by the severity of her pain, its accompaniments, and the treatment that is required to relieve symptoms. Impairment is intermittent, lasting only the duration of the attack and the effects of the medication. She is otherwise unimpaired. (emphasis added)

The Tribunal's reasons 46 The Tribunal concluded that the extract from the AMA Guides (at 570), set out at [36] above, made "it clear that the AMA 5 does not apply to Ms Wuth's situation". It found that she did "not have a 'conventional impairment rating' with which to 'combine' any 'discretionary quantitative pain-related impairment'" (at [54]). It distinguished example 18-1 by noting that, while the impairment rating discussion in that example gave the examiner an option to award 1%, 2% or 3% quantitative impairment, it also stated that there was no rateable impairment based on organ or body part dysfunction. The Tribunal found that the use of example 18-1 confirmed its view that the AMA Guides did not provide impairment ratings for Ms Wuth's condition (at [55]). 47 Next, the Tribunal noted that principle 12 in Pt 1 of the approved Guide suggested that migraine or tension headaches could be assessed under the AMA Guides. But, it found, that any such assessment could only be made if the examiner could arrive first at a conventional impairment rating. The Tribunal said the AMA Guides could only be used to assess the degree of additional pain-related impairment due to headaches. Accordingly, it concluded that the AMA Guides could not be used in accordance with the provisions of Pt 1 of the approved Guide to give a quantitative rating for Ms Wuth's condition. Rather, the Tribunal found, her whole person impairment had to be assessed using clinical judgment, as the AMA Guides had stated in [1.5], headed "Incorporating Science with Clinical Judgment" (AMA Guides at 11): In situations where impairment ratings are not provided, the [AMA] Guides suggests that physicians use clinical judgment, comparing measurable impairment resulting from the unlisted condition to measurable impairment resulting from similar conditions with similar impairment of function in performing activities of daily living. (emphasis added) 48 In those circumstances, the Tribunal proceeded to make its own, lay "clinical judgment" of the percentage degree of Ms Wuth's permanent impairment under s 24(6) of the SRC Act. It found that, using tables in Ch 13 of the AMA Guides, her level of impairment should be rated having regard to the analogy of her impairment with the upper end of the class 1 range (of 0%-14%) in each of: consciousness and awareness, namely "minimal limitation" of the activities of daily living, rather than using the class 2 criterion of "moderate limitation" (of between 15%-39%); episodic loss of consciousness or awareness, namely for a disorder that "limits daily activities", rather than using the class 2 criterion of "interferes with some daily activities" (of between 15%-29%). 49 The Tribunal said that it was possible that Ms Wuth's impairment was analogous to the class 2 criteria for each condition, but that there was not sufficient evidence to make such a finding. It concluded that, on the medical evidence, Ms Wuth's degree of whole person impairment was 14%. 50 The Tribunal noted that: Assoc Prof White had used Table 12.5.3 in Pt 1 of the approved Guide, but it found that this Table could not be used by it. It also noted that Dr Seneviratne had opined that Ms Wuth had no "work capacity for pre-injury duties"; there was no inconsistency between its finding that Ms Wuth's degree of impairment was 14% for the purposes of s 24 of the SRC Act and her independent entitlement to compensation based on her incapacity for work as a result of her injury under s 19 of that Act; the approved Guide provided in Pt 2 that, in defence force related claims, the degree of impairment from a condition like Ms Wuth's could be assessed under Table 13.1 of Pt 2 at up to 95%. The Tribunal found that if it could have used that table to assess Ms Wuth's impairment it was very likely that it would have assessed her degree of impairment "at 14% or more". That was because, it said, Table 13.1 in Pt 2 provided that: The degree of impairment can be assessed at 10% if: Episodes occur 12 or more times a year and cause minor interference with activities of daily living or episodes occur less frequently and cause interference with all activities of daily living other than self care. The degree of impairment can be assessed at 20% if: Episodes occur up to 25 percent of the time and cause significant interference with most activities of daily living other than self care.

Comcare's submissions 51 As to ground (1) (see [30] above): Comcare argued that the Tribunal misconstrued Ch 18 of the AMA Guides in finding that Ms Wuth's pain-related impairment was unrateable. It argued that she had a well-established medical condition, namely a chronic migrainous condition, that could be, and should have been, evaluated in accordance with Ch 18 and, hence, was rateable. It argued that Ch 18 did not require: (a) the making of a qualitative assessment in addition to an extant rating under another chapter in the AMA Guides; (b) the existence of a conventional impairment rating as a condition precedent to the use of the protocol in [18.5(5)] (set out at [44] above). Rather, Comcare submitted, that protocol "was only a 'sample'. It is not drafted as if it were a series of legal tests appearing in legislation"; (c) that the protocol not be used and, Comcare contended that, properly construed, [18.5(5b)], arguably, applied to Ms Wuth's condition, since the burden of her illness, arguably, was "slightly greater than [that of] a person with no conventional impairment rating". Comcare contended that, accordingly, Ms Wuth had an effective 0% rating, in the absence of a conventional impairment rating, and the Tribunal could award here 1%, 2% or 3% for her condition, as supported by example 18-1; (d) Comcare contended that the reasoning of Buchanan J in Broadhurst v Comcare (2010) 189 FCR 561 at 573-574 [56]-[59] did not apply to render Ch 18 of the AMA Guides inapplicable to the assessment of Ms Wuth's degree of impairment. 52 As to ground (2): Comcare argued that the Tribunal erred in using the "clinical judgment" impairment evaluation method, because that method was only open to be used where an impairment rating for a particular impairment had not been provided under Ch 18 of the AMA Guides, and Ch 18 did provide such ratings of between 0% and 3% for Ms Wuth's condition. Comcare's submissions acknowledged that this argument depended on the correctness of its argument on ground (1). 53 As to ground (3): Comcare submitted that the Tribunal erred in applying its own "clinical judgment" in arriving at the 14% impairment rating because it lacked the medical qualifications to do so. 54 As to ground (4): Comcare contended that the Tribunal did not put to it or Ms Wuth that it might attempt to make a clinical judgment to evaluate the percentage degree of her whole person impairment or would, or could, conclude that it was 14%. Since the Tribunal had no medical qualifications, Comcare argued, it was not open to the Tribunal to rely on its own expertise. Comcare relied in support of that contention on remarks by Lowe J in R v Milk Board; Ex parte Tomkins [1944] VLR 187. Moreover, Comcare submitted, the Tribunal did not have medical opinion evidence before it with which to make its determination of 14% impairment, including as to matters in Tables 13-2 and 13-3 of the AMA Guides. Comcare argued that the Tribunal should have given it the opportunity to make submissions on that question. 55 Comcare contended that the Tribunal's decision on Ms Wuth's degree of impairment should be set aside and that issue be remitted for determination by the Tribunal in accordance with law.

Consideration - Grounds (1) and (2) 56 I am of opinion that it was open to the Tribunal to find that Ms Wuth's pain-related impairment was unrateable in accordance with Ch 18 of the AMA Guides. Comcare's argument was fallacious. It relied on example 18-1 and [18.5(5)] to support a proposition that the maximum percentage degree of impairment that it is possible to award for any headache condition, including Ms Wuth's chronic migrainous headache condition, is 3% and that the only possible course of action open to a decision maker was to award between 0% and 3%. However, that result does not follow from Ch 18. Indeed, example 18-1 gave a maximum assessment of 3% to a person suffering a much less severe impact on her activities of daily life, and used the words "[t]he examiner has the option of awarding 1%, 2%, or 3% quantitative impairment". 57 If Comcare were right, the "option" in example 18-1 was not an option to decide to award any quantitative percentage or to conclude that the person's condition was unrateable, but rather was one that, no matter how severe the impact of the pain related impairment on the person's activities of daily life and no matter that the decision maker came to the conclusion that the impairment was "unrateable" in accordance with the principles in Ch 18, the maximum percentage awardable could never exceed 3%. 58 That is not how Ch 18 of the AMA Guides should be construed. That chapter contemplated that a qualitative assessment or rating can be made for a person who has only a pain-related impairment, but one far more severe than the "mild" qualitative degree of the hypothesised woman in example 18-1. Chapter 18 gave no examples of a person with a more severe degree of qualitative impairment being awarded a percentage rating. And, Ch 18 also contemplates that at various points in the performance of an attempt to make a quantitative percentage rating of pain-related impairment, the examiner can, and where appropriate will, decide that in all of the circumstances, the impairment is "unrateable". The meaning of "unrateable" as used in Step VIII in [18.3d] and Step 6 in [18.5] must mean that the examiner can conclude, at least at those times, that, even though he or she had until then proceeded on the basis that the impairment was or might be rateable quantitatively under Ch 18, in light of undertaking the preceding steps in the relevant protocol, it was in fact unrateable. 59 The AMA Guides stated (at 570) that Ch 18 "assessed pain qualitatively". The authors' reason for this approach had been that first, "impairment ratings for pain disorders" had not been given in Ch 18 deliberately because such ratings had not been tested on a widespread basis, and secondly, qualitative assessments or "ratings" for such impairments could assist an administrative decision maker, such as Comcare or the Tribunal, to allocate compensation to a person with a condition for which Ch 18 deliberately eschewed giving a percentage or range. 60 The introduction to [18.3d] (set out at [42] above) stated that under Ch 18 "ADL [activities of daily living] deficits are given the greatest weight". In Steps III and IV of the protocol in [18.3d], the examiner had to proceed to Step VI after assessing whether the pain-related impairment had increased the burden of the person's condition either slightly or substantially. Step VI then required a determination whether that impairment was rateable or unrateable, with the consequence of attracting either Step VII or Step VIII. Correspondingly, [18.5(5)] applied only if the examiner determined the impairment to be rateable, while [18.5(6)] applied where it was unrateable. Critically, each protocol in [18.3d] and [18.5] was structured on the relationship between the pain-related impairment and its slight or substantial increase in the burden of another condition that the person had. 61 The chronic migrainous headache condition from which Ms Wuth suffered was the only relevant condition that burdened her, and it burdened her so much that she could not continue to work because of its impact on her activities of daily living. Hers was not a condition that the Tribunal found fell within Steps III or IV of the protocol in [18.3d]. That was because it lacked the nexus with an increase in the burden of another condition. Pain from a back condition is one thing; pain as the only condition, the impairment of which had to be assessed, based on its own disabling effect, is another. That is why example 18-1 recognised that some mild headache pain-related impairment conditions could be determined, at the examiner's option, to be either rateable to 3% or unrateable. 62 The purpose of [18.5(5)] and [18.5(6)] was to grant the examiner a discretionary, but not obligatory, means of awarding a rating of 0%, 1%, 2% or 3% in combination with a conventional impairment rating, but only where the examiner, after following the methodology in Ch 18 for a prima facie rateable condition, ultimately considered that the pain-related impairment was rateable. If the mild pain-related impairment in example 18-1 had to be rated, as Comcare asserted, only with a percentage rating of 0%, 1%, 2% or 3% under Step [18.5(5b or c)], then a pain-related impairment for the other three more serious categories of impairment noted in [18.5(3e)] and Table 18-3, namely moderate, moderately severe and severe, although substantively different from "mild" in a qualitative sense, could never be rated higher than a 3% mild pain-related impairment. However, Step VII in the protocol in [18.3d] gave the examiner a discretion to "award quantitative pain-related impairment of up to 3%" if the impairment was rateable, but Step VIII stated that the examiner should not award any such percentage where the impairment was unrateable. 63 Here, each of Assoc Prof White and Dr Seneviratne found that he could not convert the pain-related impairment qualitative scores at which they had arrived for Ms Wuth under Table 18-6, of 36 (moderate) and 19.6 (mild) respectively, to a percentage rating under the approved Guide. And Dr Seneviratne opined that there was no whole person impairment for her condition under the AMA Guides because there was no rateable impairment based on organ or body part dysfunction. 64 I am of opinion that Ch 18 is not drafted, and cannot have been intended, to limit the decision maker to awarding no more than 3% for a pain-related impairment even though the impact on the person's activities of daily living from, say, chronic migrainous headache was such that they could not work or function at all, if, as [18.3d] stated, "ADL deficits are given the greatest weight". 65 In that context, it is critical to return to what the authors of the AMA Guides set out in [18.3] (at 570), that I have quoted at [36] above, namely that Ch 18 "assesses pain qualitatively" not quantitatively. The authors revealed why the principles in Ch 18 are not appropriate for the purpose for which Comcare contended. That is because, in the authors' words: percentages for pain-related impairment have not been used and tested on a widespread basis, as have other impairment ratings used in the [AMA] Guides, it was decided that impairment ratings for pain disorders would not be expressed as percentages of whole person impairment. (emphasis added) 66 The result that Comcare asserted must be produced by using the 3% discretionary supplement as setting a mandatory upper limit for a percentage amount of whole person impairment, no matter how disabling a pain-related impairment may be, is the very reason why the authors of the AMA Guides did not write Ch 18 to prescribe, in the ordinary course of assessing pain-related impairment, a percentage, or quantitative, assessment method. Comcare's argument would lead to an unreasonable and arbitrary result. The instance in example 18-1 does not negate this reasoning for, as I have explained, it gave an examiner, unusually in a prescriptive, quantitative context, an option, but not an obligation, to award up to 3% for a pain-related impairment in some instances at the lowest (mild) end of the qualitative assessment descriptive scale and in others, where the qualitative assessment was greater and associated with a substantive organ or bodily dysfunction for which a percentage rating already had been given. 67 Properly understood, the purpose of Ch 18 was to provide a qualitative assessment methodology that decision makers could use as a reasonable basis for awarding compensation, including where that depended, as under ss 24(6) and 28(4) of the SRC Act, on attributing a percentage for permanent impairment. The lay decision maker could form his, her or its own opinion as to the appropriate percentage, guided by the medical assessment, in accordance with Ch 18, of the qualitative degree and manifestation of any pain-related impairment. 68 However, the discretionary power given to an examiner to award up to 3% for rateable pain-related impairment, ordinarily was intended to reflect the additional quantifiable impact of a pain condition occasioned by another rateable and rated injury, as the instances in Ch 18 other than example 18-1 demonstrated. 69 There is no inconsistency between acknowledging, as stated in the third paragraph in [18.3a], summarised at [37] above, that most well-established pain syndromes, such as "Headache (most)" in Table 18-1, can be "evaluated on the basis of concepts elaborated in this chapter" and concluding that such a syndrome is nonetheless unrateable, in the sense of assigning a percentage whole person impairment figure. Thus, [18.3d] set out an overview "How to Rate Pain-Related Impairment" that included the examiner making clinical judgments at Steps II, III and IV, that were connected to whether or not a conventional rating for an impairment other than pain-related adequately had encompassed the impact of the pain syndrome experienced or reported by the person being assessed, or at Step VI, that was an overall evaluation of whether the pain-related impairment was or was not rateable. 70 Importantly, as Steps IV and V showed, a formal pain-related impairment assessment itself provided "quantitative ratings of an individual's pain behaviour and credibility" but not of his or her pain-related impairment. That is why the second reason given in [18.3c] for distinguishing unrateable pain-related impairment from the rateable is important here. It recognised that there is no, and that the AMA Guides were not providing a, reliable, valid whole person impairment percentage rating methodology for pain-related impairment, but rather they were providing a method for expressing a qualitative assessment. 71 The fact that a condition, such as Ms Wuth's chronic migrainous headache, could be described as, prima facie, "rateable" in light of its meeting affirmatively each of the three questions in [18.3b], set out at [38] above, does not mean that the AMA Guides intended that examiners had to assign to all such conditions a percentage whole person impairment rating limited to no more than 3%. To the contrary, [18.3b] required the examiner to use the protocols in [18.3d] and [18.5], each of which provided steps (Step VI in [18.3d], Step 6 in [18.5]) where the examiner, again, had to address whether the condition was rateable or unrateable. 72 The word "rateable" as used in [18.3b] referred distributively to each of the quantitative and qualitative rating systems described in Ch 18. A condition could be "rateable" in answer to the three questions in [18.3b] because it could be assessed using the qualitative rating system in Ch 18, yet be "unrateable" quantitatively when the examiner came to Step VI in [18.3d] or Step 6 in [18.5] because "percentages for pain related impairment have not been used and tested on a widespread basis, as have other impairment ratings used in the [AMA] Guides" (see [18.3] at 570, set out at [36] above). 73 As McHugh, Gummow, Kirby and Hayne JJ said in Project Blue Sky Inc v Australian Broadcasting Authority (1998) 194 CLR 355 at 381 [69]: The primary object of statutory construction is to construe the relevant provision so that it is consistent with the language and purpose of all the provisions of the statute [See Taylor v Public Service Board (NSW) (1976) 137 CLR 208 at 213, per Barwick CJ]. The meaning of the provision must be determined "by reference to the language of the instrument viewed as a whole" [Cooper Brookes (Wollongong) Pty Ltd v Federal Commissioner of Taxation (1981) 147 CLR 297 at 320, per Mason and Wilson JJ. See also South West Water Authority v Rumble's [1985] AC 609 at 617, per Lord Scarman, "in the context of the legislation read as a whole"]. In Commissioner for Railways (NSW) v Agalianos [(1955) 92 CLR 390 at 397], Dixon CJ pointed out that "the context, the general purpose and policy of a provision and its consistency and fairness are surer guides to its meaning than the logic with which it is constructed". Thus, the process of construction must always begin by examining the context of the provision that is being construed [Toronto Suburban Railway Co v Toronto Corporation [1915] AC 590 at 597; Minister for Lands (NSW) v Jeremias (1917) 23 CLR 322 at 332; K & S Lake City Freighters Pty Ltd v Gordon & Gotch Ltd (1985) 157 CLR 309 at 312, per Gibbs CJ; at 315, per Mason J; at 321, per Deane J]. (emphasis added) 74 Moreover, I agree with the reasoning of Buchanan J in Broadhurst 189 FCR at 573-574 [56] that the statutory instruction in s 24 of the SRC Act, that a person in Ms Wuth's position be compensated unless the degree of her permanent impairment is less than 10%, cannot be defeated by the adoption of an administrative procedure in the approved Guide, or, for that matter, its incorporation of a part of the AMA Guides, "which denies the material which is necessary to assign (or not assign) a 10% value for impairment and instructs that an impairment is" a percentage less than 10%, namely no more than 3%, no matter how substantively disabling it is. 75 There would be no intelligible purpose in the approved Guide requiring a person suffering from a headache condition to be assessed under the AMA Guides, if the AMA Guides provide that the individual can never be awarded more than 3% whole person impairment. If that is what the approved Guide has done (which I do not consider it has) the requirement for an assessment under Ch 18 of the AMA Guide would be an empty and cruel farce inflicted on a person, such as Ms Wuth, who had suffered such a significant work-related injury that she lost her job because of her invalidity. 76 Rather, the approved Guide's reference to the AMA Guides for assessment of conditions of migraine or tension headaches, having regard to the principles of policy, consistency and fairness to which Dixon CJ referred in Commissioner for Railways (NSW) v Agalianos (1995) 92 CLR 390 at 397, was intended to result in a principled qualitative, not quantitative, assessment (at least in cases where no organ or body part dysfunction was involved) on which an administrative decision maker, such as Comcare or the Tribunal, could act in accordance with s 28(4) of the SRC Act to assign a percentage under s 24(6) based on a lay "clinical judgment". 77 For these reasons, the Tribunal did not misconstrue Ch 18. It follows that I would dismiss grounds (1) and (2) of Comcare's appeal.

Consideration - Ground (3) 78 In that context, the Tribunal was entitled to use its own "clinical judgment" or make its own assessment in accordance with Ch 18, including Step VIII in [18.3d] and Step 6 in [18.5]. The Tribunal needed no medical qualifications to do. It was performing the administrative function of using the qualitative assessments by Assoc Prof White and Dr Seneviratne to arrive at its own assessment of a percentage amount of Ms Wuth's permanent impairment in accordance with ss 24(6) and 28(4) of the SRC Act. Ground (3) also fails.

Consideration - Ground (4) 79 In my opinion, Comcare was not denied any procedural fairness. The Tribunal had before it a contested question of construction as to how Ch 18 of the AMA Guides applied and competing medical assessments, including expert evidence, as to the magnitude of the qualitative pain-related impairment of Ms Wuth. Both of the medical experts qualified by the parties had opined that Ms Wuth could not be assigned a percentage whole person impairment under the approved Guide or AMA Guides for her chronic migrainous headache pain-related impairment. The AMA Guides expressly provided in Ch 18 at [18.3c] (at 572) for such a situation by requiring an examiner (or, as in this case, qualified experts who gave evidence to the Tribunal) to perform a qualitative assessment of a person's pain-related impairment when that impairment could not be rated quantitatively "so that administrative agencies can make informed decisions about whether or not to compensate these individuals". 80 The Tribunal stood in Comcare's decision-making shoes and had to make a decision on the issues before it, including whether to award a percentage as the degree of Ms Wuth's permanent impairment under s 24(6) of the SRC Act. The Tribunal's function in that situation required it to act on the evidence and give what it considered to be the correct or preferable decision: Wilson v Minister for Aboriginal and Torres Strait Islander Affairs (1996) 189 CLR 1 at 18 per Brennan CJ, Dawson, Toohey, McHugh and Gummow JJ. That is what it did on the medical evidence before it. 81 Comcare knew all of this at the hearing in which the Tribunal had to exercise its decision-making function to decide Ms Wuth's application for compensation under s 24. How Comcare could say that it did not have the opportunity to put its case as to what Ms Wuth should be awarded is shrouded in mystery. Comcare submitted to the Tribunal that she should get nothing because of its contention that the maximum percentage available was 3% and, since that was below the 10% minimum in s 24(7), her claim had to fail. Comcare knew that none of the doctors whose reports were in evidence had ascribed a percentage for her degree of impairment, but that was what Ms Wuth wanted the Tribunal to do. 82 There was no evidence from any officer of Comcare that it understood that the Tribunal was not engaged in a hearing of Ms Wuth's whole claim for a decision under s 24, including under ss 24(6) and 28(4). Ms Wuth's counsel asked the Tribunal in final submissions to make a clinical judgment. It had power under s 33(1)(c) of the AAT Act to do so, by informing "itself on any matter in such manner as it thinks appropriate". Comcare had the opportunity of being heard on the substantive issue. It did not put to the Tribunal that it should not do as counsel for Ms Wuth had sought. 83 The Tribunal's function in that context was to make a decision about the ultimate question that it had to resolve, namely what percentage should it assign under ss 24(6) and 28(4). Comcare did not begin to explain what else it might have done had it somehow not appreciated that the role of the Tribunal was to make the very decision that ss 24(6) and 28(4) required it to make. As Gleeson CJ said in Re Minister for Immigration and Multicultural and Indigenous Affairs; Ex parte Lam (2003) 214 CLR 1 at 14 [37]: Fairness is not an abstract concept. … Whether one talks in terms of procedural fairness or natural justice, the concern of the law is to avoid practical injustice. 84 Comcare has shown no practical injustice here. Moreover, unlike in cases such as R v Milk Board [1944] VLR at 197 and Commissioner of Patents v Emperor Sports Pty Ltd (2006) 149 FCR 386 at 392 [24] per Heerey, Kiefel and Bennett JJ, the Tribunal was not using "clinical judgment" as an expert medical practitioner. It was using the evidence before it, including the expert evidence, to make the evaluative administrative decision where the approved Guide and the AMA Guides did not provide a quantitative value or range of values for determining the percentage degree of Ms Wuth's permanent impairment under s 24(6). 85 The SRC Act did not require the Tribunal to be constituted by a person with any particular qualifications. Had the Tribunal been constituted by a judge, and it could have been, Comcare's argument would be unsustainable since judges routinely make such evaluative decisions based on the evidence adduced by the parties. Likewise, both the AAT and SRC Acts require administrative decisions to be made on evidence before the decision maker using the evaluative tools in that evidence and the decision maker's own judgment based on that evidence. In my opinion ground (4) fails.

Conclusion 86 For these reasons the appeal should be dismissed with costs and the cross-appeal allowed with costs. Ms Wuth is entitled to an order that the Tribunal's decision include a direction that Comcare pay her costs of both applications before it. I certify that the preceding eighty-six (86) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justice Rares.