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.