IN THE SUPREME COURT OF VICTORIA	Not Restricted	
AT MELBOURNE
COMMON LAW DIVISION
JUDICIAL REVIEW AND APPEALS LIST
S ECI 2024 00734

BETWEEN:

TERRY GRAY	Plaintiff	
		
v		
		
VICTORIAN WORKCOVER AUTHORITY	First Defendant	
		
and		
		
PROF ANDREW SIZELAND	Second Defendant	

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JUDGE:	Forbes J	
WHERE HELD:	Melbourne	
DATE OF HEARING:	10 October 2024	
date of JUDGMENT:	6 November 2024	
CASE MAY BE CITED AS:	Gray v Victorian WorkCover Authority & Anor	
MEDIUM NEUTRAL CITATION:	[2024] VSC 680	
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ADMINISTRATIVE LAW — Judicial review — Medical panel opinion — Plaintiff claimed in respect of hearing loss and tinnitus — Accepted injury in respect of hearing loss; tinnitus rejected — Medical questions referred to a medical panel — Panel assessed loss of hearing pursuant to chapter 9 of the American Medical Association Guides to the Evaluation of Permanent Impairment (‘AMA Guides’) – Panel assessed impairment of 0% in respect of tinnitus — Whether Panel misapplied the AMA Guides — Scardamaglia v Amcor Pty Ltd & Anor [2023] VSC 114, Amcor PLC v Scardamaglia [2023] VSCA 290 — Irwin v Victorian WorkCover Authority & Anor [2024] VSC 615 — No error — Proceeding dismissed.
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APPEARANCES:
	Counsel	Solicitors	
For the Plaintiff	B McManamey	Industrial Deafness Australia	
			
For the First Defendant	R Kumar
E Golshtein	Hall & Wilcox	
			
For the Second Defendant	No appearance	DLA Piper Australia	

Contents
A	Introduction
B	Grounds of review
C	Principles
D	The methodology of assessment
E.	The Panel’s decision
E	Further Evidence
F	Submissions
G	Consideration
H	Annexure A

HER HONOUR:
A	Introduction
1	Mr Terry Gray (the plaintiff) seeks judicial review of a medical panel opinion. The medical panel (the Panel) was constituted under the Workplace Injury Rehabilitation and Compensation Act 2013 (Vic) (the WIRC Act). The Panel assessed the plaintiff’s degree of impairment arising from hearing loss as a result of employment. The opinion of the Panel dated 10 January 2024 calculated the whole persona impairment at 0%. The accepted noise induced binaural hearing loss was assessed at a loss of 9.4%. The Panel gave no additional impairment percentage for the presence of tinnitus under Chapter 9 of the American Medical Association’s Guides to the Evaluation of Permanent Impairment (4th Ed) (the AMA Guides). 
2	Included in the material before the Panel was an assessment of Mr Leigh Watson, audiologist, contained in a report dated 20 September 2022 which accompanied the plaintiff’s claim for an impairment benefit. Mr Watson concluded there was a 19% compensable binaural hearing loss (which included 5% for tinnitus). The Panel also had the report Dr T John Redhead arranged by the claims agent, who assessed the plaintiff’s work-related noise induced hearing loss at 7.9% which equated to 0% whole person impairment. Dr Redhead also gave no additional impairment for tinnitus.
3	The plaintiff challenged the assessment of Dr Redhead relied on by the claims agent. The Panel was constituted by Professor Andrew Sizeland. He will abide by the Court’s determination.
B	Grounds of review
4	Ground 1 is that the Panel did not assess diminution of hearing in accordance with point 5a of the Australian Society of Head and Neck Surgery Guidelines (the ASOHNS Guidelines). It said that the Panel erroneously relied on the lowest threshold reading on the audiogram, regardless of whether it was a reliable threshold.
5	Ground 1A identifies an inadequacy in the reasons provided because the Panel failed to explain why it interpreted and chose the audiogram results that it relied on to calculate hearing loss. Counsel for the plaintiff at hearing submitted this ground also gives rise to an argument as to whether the AMA Guides have been properly applied. The submissions also raise an argument as to whether the Panel has failed to consider the evidence of Mr Leigh Watson. 
6	Ground 2 identifies an error in applying the AMA Guides which provide that where ‘tinnitus in the presence of unilateral or bilateral hearing loss may impair speech discrimination … an impairment percentage up to 5% may be added to the impairment for hearing loss’. This ground alleges that the Panel assessed the impairment of speech discrimination having removed the effects of hearing loss, and so has failed to assess speech discrimination ‘in the presence of bilateral hearing loss’. 
7	The grounds of appeal raise the following issues:
(a)	In assessing industrial deafness did the Panel err in interpreting the audiogram by not correctly applying the ‘lowest (least hearing loss) reliable thresholds obtained’ as required by point 5a of the ASOHNS Guidelines?;
(b)	Did the Panel erroneously consider speech discrimination resulting from hearing loss after having removed the effects of hearing loss, and so not in accordance with the AMA Guides. and
(c)	Are the Panel’s reasons inadequate in two respects:
(i)	For failing to explain why it chose the relevant hearing loss thresholds when applying the ASOHNS Guidelines; and
(ii)	By failing to consider or explain why it disagreed with the findings of Mr Watson.
C	Principles
8	No question of statutory construction arises of any part of subdivision 3 of Part 2 of the WIRC Act dealing with industrial deafness.
9	The assessment of Mr Gray’s industrial deafness is deemed to have occurred on his last day of performing duties or his exposure to noisy conditions, and is assessed in accordance with s 63(4) of the WIRC Act which provides that diminution of hearing is assessed as a binaural loss of hearing and determined in accordance with the Improved Procedure for Determination of Percentage Loss of Hearing (1988th edition or later prescribed edition) published by the National Acoustic Laboratory (the NAL Procedure). This has the effect of removing the methodology for assessment contained in tables 1, 2 and 3 in chapter 9 of the AMA Guides. 
10	Further, the Minister has approved the ASOHNS Guidelines for determining the percentage diminution of hearing for the purposes of the WIRC Act. The approval was made under various legislative provisions including s 63(4)(a)(ii) of the WIRC Act. 
11	The construction and interpretation of the ASOHNS Guidelines and, insofar as it is relevant, Chapter 9 of the AMA Guides does not proceed as if those documents were legislation. The relevant legal question is whether the assessment of hearing loss has been undertaken ‘in accordance with’ the AMA Guides, approved procedures and guidelines. It is the task of medical practitioners to construe and apply those documents. As was said in Vicinity Centres PM Pty Ltd v Arik, confirming earlier statements in Gamble v Emerald Hill Electrical Pty Ltd:
…the Act requires the Panel to apply the Guides using members’ individual and collective skill and expertise as medical practitioners and that their approach to the Guides is not to be supplanted merely because the court comes to a different view as to how it might be interpreted. It is necessary to go further and show that the methodology is not in accordance with the Guides, being a document intended for application by medical practitioners. 
12	As stated at paragraph [10] above the methodology required by the AMA Guides has been modified by statute for industrial deafness to use the NAL Procedure and the ASOHNS Guidelines as approved by the Minister under s 63(4)(a)(ii) of the WIRC Act. These modifications nevertheless incorporate the AMA Guides to consider the effects of tinnitus on hearing that are additional to the effects on the pure tone audiogram, so that the entirety of diminution of hearing that is work-related is assessed.
13	Whether a hearing assessment needs to take account of a diminution of hearing not fully accounted for by the pure tone audiogram is a matter for medical expertise and requires the medical examiner to exercise their discretion in allocating a percentage within the prescribed range (0-5%) to reflect that additional impairment. 
14	In considering the assessment of tinnitus in impairment of hearing, O’Meara J in Irwin v Victorian WorkCover Authority & Anor (‘Irwin’) concluded that the phrase ‘tinnitus in the presence of unilateral or bilateral hearing loss’ was used in Chapter 9 of the AMA Guides in the context of other testing of hearing loss and specifically contemplated that such testing used amplification. His Honour concluded, in this context that:
…it would appear to be rather incongruous if the combination of the phrase and sentence…should be taken to command that claimed tinnitus could not be considered by reference to features of testing which relevant parts of the AMA Guides otherwise command be performed.
15	A medical panel’s reasons must explain its actual path of reasoning by which it in fact arrived at the opinion it formed in sufficient detail to enable a court to identify whether the opinion involves any error of law. It forms its own opinion and does not adjudicate on competing opinions and is under no obligation to explain why it did not reach an opinion not held by it, even if that opinion is shown on the material before the Panel to be held by other medical practitioners.
D	The methodology of assessment
16	The ASOHNS Guidelines relevantly provide:
4.	The Audiometrical assessment
The audiometrical assessment must as a minimum include air conduction at 0.25, 0.5, 1, 1.5, 2, 3, 4, 6 & 8 kHz and bone conduction at 0.5, 1, 1.5, 2, 3 & 4 kHz for proper evaluation of the hearing loss and the determination of the impairment. It must be rigorously performed, with the test retest technique to ensure its accuracy. 
….
If there is uncertainty as to the accuracy of this pure tone audiogram, an air and bone Cortical Evoked Response Audiogram ( CERA) plus a repeat pure tone audiogram is indicated. 
…
5.	Interpretation and preparation of medical opinion
a)	Thresholds to be used
The lowest (least hearing loss) reliable thresholds obtained (including CERA) should be used as the basis for compensation. 
…
7.	Other Considerations
a)	Tinnitus
The 4th Edition AMA Guides relevant to ENT impairment assessment refers only to the effect of tinnitus on the function of the ear. This means the effect of tinnitus on hearing and any effect on the pure tone audiogram will be accounted for in the evaluation of hearing. 
Other symptoms related to tinnitus, which may adversely affect the ability to carry out the activities of daily living including anxiety and sleep disturbance, are responses to the presence of tinnitus and not directly related to hearing. 
The impairment evaluation of these aspects of tinnitus belongs in the field of specialists in psychological medicine. The ENT impairment assessor can make a recommendation that such an assessment be carried out if considered appropriate. 
17	Chapter 9.1 of the AMA Guides state:
Disturbances of the ear, such as chronic otorrhea, otalgia, and tinnitus, are not measurable. Therefore, the physician should estimate an impairment percentage based upon the severity of those conditions and the degree to which they interfere with functions of the ear, and a percentage that is consistent with established values.
Tinnitus in the presence of unilateral or bilateral hearing loss may impair speech discrimination; therefore an impairment percentage up to 5% may be added to the impairment for hearing loss. 
18	The AMA Guides go on to describe hearing impairment as reduced hearing sensitivity that is outside the range of normal. In Chapter 9.1a it states: 
Prosthetic devices must not be used during the evaluation of hearing sensitivity.
19	In Amcor v Scardamaglia (‘Scardamaglia VSCA’), the Court of Appeal said: 
The ASOHNS Guidelines note the possibility of an effect of tinnitus on hearing which is additional to an effect of tinnitus on a pure tone audiogram. In context, this additional effect of tinnitus on hearing is not some unspecified enhancement of hearing; but rather, it must be a diminution of hearing. That issue is put beyond doubt when one reads the AMA tinnitus paragraphs, to which the reader of the ASOHNS Guidelines is referred… The relevant effect of tinnitus, in the presence of unilateral or bilateral hearing loss, is the possible impairment of speech discrimination – a circumstances which could only be said to be a diminution of hearing – which may not be accounted for on a pure tone audiogram. It is in those circumstances that an assessor is given the discretion ( to be exercised in his or her independent expert opinion) to add to the impairment percentage found by reference to the provisions of the ASOHNS Guidelines, a further amount of up to 5 per cent for such a diminution of hearing. 
20	The Court specifically noted: 
Contrary to the employer’s submissions, the construction [of the ASOHNS Guidelines] we prefer does not involve any duplication in the assessment of the diminution of hearing. An expert assessor is given the discretion to add a percentage (up to 5 per cent) for any additional diminution of hearing caused by tinnitus, which diminution is over and above any diminution of hearing that may have been accounted for on the pure tone audiogram. 
E.	The Panel’s decision
21	The grounds of review implicate the first question and answer of the Panel which was:
Question a) 	What is the worker's degree of permanent whole person impairment resulting from the accepted injury/s assessed in accordance with Division 4 of Part 2?
Answer: 	The Whole Person Impairment calculated in accordance with the Act is 0%. The degree of impairment is permanent.”
22	The Panel’s reasons set out the history and examination it undertook. As noted earlier, that history included that the worker has ‘ringing in both ears all the time’ and that hearing aids ‘provided some assistance in understanding what was being said on TV’. The audiogram tests were attached and the results discussed. The Panel noted that:
… the pattern of the audiogram (copy enclosed) with a downsloping mid to high frequency notched sensorineural loss sloping. The Panel considered that the sloping to notched high frequency loss was ‘characteristic’ of noise as described in paragraph 3 of point 5b of the Australian Society of Head and Neck Surgery ('ASOHNS') Guidelines, Revised 2017..
The Panel also noted paragraph 1 of point 5b of the ASOHNS Guidelines ‘The early loss and the fastest rate of deterioration are at 3, 4 & 6 kHz. … As the noise induced loss becomes more severe 2 kHz can be involved and after a period of 30 years of exposure, 1500 and even 1 000Hz to a small degree as well.’ The Panel noted that the worker had worked in employment which was described as noisy for over 30 years and further noted the pattern of hearing loss with a sloping loss from 1 kHz and therefore concluded that based on this configuration of the graph (paragraph 3 of point 6c of the ASOHNS Guidelines) that losses from 1 to 4 kHz represented possible noise related hearing loss but thresholds below 1 kHz were degenerative.
23	The Panel also noted point 5a of the ASOHNS Guidelines which specify that ‘the lowest (least hearing loss) reliable thresholds obtained (including CERA) should be used as the basis for compensation.’
24	The Panel set out the calculations used to arrive at a binaural loss of hearing of 14.3% before making a deduction for presbycusis to arrive at a noise induced hearing loss of 9.4%.
25	Those calculations to arrive at 14.3% were:
1kHz 15/15=0; 1.5kHz 20/20=0.6; 2 kHz 30/30=2.1; 3 kHz 50/50=4.8; 4 kHz 65/70=6.8
26	The audiogram and its key, upon which these calculations of the Panel are based is set out at Annexure A to these reasons.
27	The Panel then turned to consider the presence of tinnitus. The Panel’s reasons addressed this aspect as follows:
The Panel noted the recent judgment Amcor PLC v Scardamaqlia, Felice & Lyons, A/Prof Bernard [2023] VSCA 290 wherein the Judges found that when reading the AMA tinnitus paragraphs, to which the reader of the ASOHNS Guidelines is referred in the first of the ASOHNS tinnitus paragraphs; the relevant effect of tinnitus, in the presence of unilateral or bilateral hearing loss, is the possible impairment of speech discrimination - a circumstance which could only be said to be a diminution of hearing - which may not have been accounted for on a pure tone audiogram. It is in those circumstances that an assessor is given the discretion (to be exercised in his or her independent expert opinion) to add to the impairment percentage, found by reference to the other provisions of the ASOHNS Guidelines, a further amount of up to 5 per cent for such a diminution of hearing. The Judges found that Judge Forbes was correct when they concluded that the Medical Panel erred when it failed to consider the effect of tinnitus on Mr Scardamaglia’s hearing as provided by the ASOHNS Guidelines. Accordingly, the Supreme Court judgment Scardamaglia, Felice v Amcor P/L & Lyons, A/Prof Bernard [2023] VSC 114 stands and a Panel should in its reasons show the parties that it has provided allowance for tinnitus, indicating a figure between 0% and 5% supported by adequate reasons.
The Panel noted page 9/224 of the Fourth Edition Guides which states ‘tinnitus in the presence of unilateral or bilateral hearing loss may impair speech discrimination; therefore an impairment percentage of up to 5% may be added to the impairment for hearing loss’. The Panel noted that the worker described no difficulty with discrimination when the volume was elevated or in quiet situations (where the tinnitus would still be present) and furthermore noted its audiological testing showed 100% (normal) speech discrimination scores once the effects of hearing loss had been removed. The Panel noted that amplification is an inherent component of audiological testing and is not the same as the fitting of a prosthesis. The Panel considered that amplification in audiological testing is used to correct for reduced hearing acuity and only in this respect could it be considered similar to the fitting of a prosthesis. The Panel also noted that there is no known prosthetic treatment for tinnitus and therefore no test procedure that could be interpreted to act as a prosthesis. The Panel also noted that tinnitus is a condition of experiencing noise in the ear and does not directly cause hearing loss. The Panel additionally noted that tinnitus is a stable condition which is still present and unaffected by amplification, although amplification could at times interfere with the subject’s perception of tinnitus. The Panel observed that, once amplification had corrected for the hearing loss due to noise trauma, the discrimination returned to normal. The Panel therefore concluded that the residual tinnitus, which was still present, did not affect discrimination. The Panel finally concluded that there was an impairment percentage of 0% for the effect of tinnitus as the condition does not interfere with the function of the ear and does not impair speech discrimination.
The Panel therefore concluded that the worker has a 9.4% binaural hearing loss relevant to the accepted noise induced hearing loss injury.
E	Further Evidence
28	In this proceeding, the plaintiff included two reports not before the Panel. One, was from Ms Michelle Kerr who undertook calculations based upon the audiogram of 6 December 2023 relied on by the Panel using the NAL Procedure tables. Her calculations were based on air conduction thresholds only. The second was a medicolegal report of Dr Paul Fagan, responding to a letter dated 12 February 2024. The defendant objected to the tender of this evidence on the basis that it was not before the Panel and did not fall into the recognised exceptions for the receipt of new evidence. The defendant relied on City of Melbourne v Neppessen to submit there is no role for evidence on the merit of a medical panel opinion, nor on the questions of law as to the interpretation of the AMA Guides on the material before the Panel. 
29	By his reply submissions, the plaintiff identified the purpose of the new evidence as that of ‘background to assist in the proper interpretation of the [AMA] Guides’. It is not intended to challenge factual findings or support a merits review. 
30	The plaintiff ultimately sought to rely on limited portions of the Fagan report only. It was submitted that reliance on the report was solely for the purpose of assisting the Court to understand the technical difference between air conduction and bone conduction assessments. Reliance was therefore limited to several particular sentences. One, stating that testing by air conduction is done directly though the ear canal and eardrum replicating how we naturally hear while bone conduction measures sound transmitted through soft tissue, skin and bone. Another was a sentence stating that physicians do not diagnose middle ear problems only at specific frequencies, and finally, that taking the air conduction threshold at one frequency and sporadically the bone conduction or CERA threshold at others in the same ear, is medically absurd. 
31	In my view the specific content of Fagan’s report does not provide assistance in understanding the technical differences between air conduction and bone conduction methods or assessment in any technical way. In circumstances where the ASOHNS Guidelines mandate use of both methods at particular frequencies, the report did not elucidate any relevant technical differences in testing. Rather, the purpose and tenor of the report was to provide an opinion as to the relative reliability of the two methods. The extract of the report does not fall into any of the accepted categories for admission as evidence not before the decision maker. In any event, were it admissible I would have found it of negligible weight. For reasons expressed later, the relative reliability of the two methods is not relevant. 
F	Submissions
32	By ground 1 the plaintiff submits that the lowest reliable thresholds means either the air conduction, or bone conduction or CERA as a whole must be used. Selecting thresholds from different methods at various frequencies is not permitted. Relying on Dr Fagan’s opinion, it submitted to do so is a medical absurdity. It is apparent from the graph and the calculations set out in the Panel’s reasons that the assessor used a mixture of findings from both assessments to determine the lowest threshold at each individual level. He did so without giving consideration to which assessment was the more reliable or providing reasons for the selection of each reading. He submits that the ASOHNS Guidelines provide no information as to what is meant by reliable. The plaintiff contends that usual medical practice is to use air conduction thresholds unless those results are unreliable in which situation bone conduction is used. Either way, one method of assessment is used and not a combination of both.
33	On this issue the defendant contends that bone conduction results were relied on at 1000 and 1500 kHz for the left ear and 3000kHz for both ears, and otherwise air conduction results were relied on. Although air conduction results at 1000 and 1500 kHz were higher, the defendant submitted that the argument that air conduction studies were ‘inherently more reliable’ at these levels should not be accepted. The defendant distinguished the requirement to use the lowest assessment from the requirement to select the reliable threshold. The lowest reliable threshold involves a choice between a reading that is reliable and another which, though lower is not considered reliable. This involves the application of medical expertise and judgment in interpreting the audiogram. The defendant submits there is nothing in the language of the ASOHNS Guidelines, or otherwise in the instruments of the statutory framework, that require a Panel to adopt the same type of conduction threshold across all relevant readings. 
34	By ground 2 the plaintiff submits that the Panel clearly failed to assess tinnitus in the presence of bilateral hearing loss. Its reasons note that ‘audiological testing showed 100% (normal) speech discrimination scores once the effects of hearing loss had been removed’ and states that amplification is an inherent component of audiological testing which replicates the use of a hearing aid. Therefore, the effects of tinnitus were, impermissibly, only considered once the effects of hearing loss were removed by appropriate amplification. 
35	Taking the argument one step further, the plaintiff submitted that the use of amplification is, or at least equates to, the use of a prosthetic device, a hearing aid, which is prohibited by the AMA Guides. Where amplification has the same effect as a hearing aid (i.e. to eliminate hearing loss), the approach taken by the Panel seeks impermissibly to do indirectly, that which is prohibited directly. By removing the effects of hearing loss, the Panel has impermissibly measured speech discrimination in the absence of hearing loss.
36	A further submission that the Panel failed to consider the other ways in which tinnitus interferes with the function of the ear, beyond speech discrimination, was not pressed at the hearing.
37	The defendant submitted that the Panel’s assessment of 0% for an additional impairment for tinnitus was in accordance with the methodology prescribed. In particular the Panel had regard to and set out its understanding of its task assessing tinnitus in light of the Court of Appeal decision in Scardamaglia VSCA. The Panel was required to and did turn its mind to whether there were effects of tinnitus not already taken into account by the pure tone audiogram. 
38	Thirdly, by Ground 1A the plaintiff submitted that the Panel’s reasons did not allow the Court to understand the basis upon which the particular thresholds were chosen as being reliable. A statement replicating point 5a of the ASOHNS was not adequate to explain why a mixture of measurement types were selected. 
39	As to the failure to give reasons for reaching a different assessment to Mr Watson the plaintiff contends that Mr Watson’s approach was in conformity with the AMA Guides as he considered the effects in the absence of amplification so reasons for any difference were required. 
40	At the outset of this hearing, the plaintiff addressed the recent decision of Irwin. Counsel accepted that in the interest of judicial comity I should follow Irwin unless satisfied that it was plainly wrong. 
41	In Irwin, his Honour concluded that the separate consideration of impairment from tinnitus did take into account the testing directed at measuring thresholds of hearing using amplification. Therefore in assessing an allowance for any additional diminution in hearing from tinnitus, the effects of amplification in the testing is taken into account. 
G	Consideration
42	The ASOHNS Guidelines specifically mandate using both air conduction and bone conduction assessment as a minimum for audiological testing. The accuracy and responsibility for medical interpretation of the audiometry results are specifically stated to rest with the assessor. The assessor must form a view about the reliability of each assessment method. Where both are reliable, at some or all frequency levels, the ASOHNS Guidelines require adoption of the lowest reliable threshold. 
43	In my view there is nothing in the language of the ASOHNS Guidelines that requires a comparison of which of air conduction, bone conduction, or where used CERA, are more reliable. Rather, the ASOHNS Guidelines require an assessor to disregard assessments that in their opinion are not reliable. There is nothing to suggest whether from a medical perspective reliability of results may affect a particular frequency, may affect one ear but not the other, or may overall produce an unreliable result. Those matters call for medical judgment. Where, as the parties agree occurred here, a mixture of bone and air conduction results are used, it must be on the basis of a medical judgment that overall both assessments produce reliable threshold losses. Indeed one might infer a medical judgment as to reliability from the similarities in the findings at the levels where both methods were used. 
44	I reject the submission that the AMA Guides, or more accurately the ASOHNS Guidelines properly read, require either bone conduction or air conduction results to be used (or by extension CERA) and does not authorise, where appropriate, a mixture of measurement methods. The ASOHNS Guidelines do not mandate an approach that adopts ‘a more reliable’ method requiring either use of an air conduction assessment or a bone conduction assessment. 
45	There are some incidental pieces of information that support this conclusion. First, the fact that the ASOHNS Guidelines mandate both assessments as a minimum suggests a belt and braces approach, even accepting that one method may be more reliable than the other at particular frequencies. Second, the NAL Procedure identifies particular difficulties with bone conduction studies at low frequency (250 Hz) and high frequencies (6 and 8 kHz). Given the requirement to test at these levels, coupled with the information that, as the reasons explained, the early and fastest rate of deterioration noise induced hearing loss are at 3, 4 and 6 kHz, at least one reason is apparent as to why the reliability of results using either method at varying frequencies involves matters of medical judgment. 
46	Further, the ASOHNS Guidelines speak of lowest reliable thresholds, not lowest reliable method. The assessor only faces a choice where two or more methods produce reliable results. In such cases, the choice is of the lowest threshold on each occasion. To the extent that the plaintiff sought to rely on the Fagan opinion that bone conduction thresholds, in the absence of middle ear pathology, gave an unreliable assessment of hearing loss, this was an opinion as to the accuracy or reliability of the method of assessment, and outside the limited basis upon which the plaintiff sought to rely on the additional evidence to explain technical terms used. Nor was the conclusion supported by any reasoning. 
47	The first ground is not made out. 
48	Two things are clear from the reasoning of the Court of Appeal in Scardamaglia VSCA. First, that tinnitus is to an extent accounted for in the pure tone audiogram results. Second, the assessor of impairment must turn their mind to tinnitus where it is present, and consider as a matter of clinical judgment whether an additional percentage is to be added, ‘over and above any diminution of hearing that may have been accounted for on the pure tone audiogram’.
49	The plaintiff’s argument is that amplification replicates the effect of a hearing aid. Therefore to consider only the effect of tinnitus that is not caught by the pure tone audiogram is in effect to consider tinnitus having removed the effect of hearing loss. This argument is flawed. Amplification, as the Panel’s reasons explain, is an inherent component of audiological testing. Amplification is used to ‘correct for reduced hearing acuity’. The purpose of amplification is to measure the extent of lost acuity.
50	The AMA Guides specifically refer to hearing levels for speech that are derived from a mean of four test frequencies of the pure tone audiogram said to ‘represent everyday auditory stimuli’. Although the calculations mandated by the AMA Guides are replaced by the NAL Procedure calculations, it seems clear to me that the pure tone audiogram does provide some measure of interference with an ability to discriminate or understand speech. The ability to provide an additional impairment for tinnitus provided for by the AMA Guides, is specifically given where an impairment of hearing loss exists. Far from accepting that the pure tone audiogram results assess tinnitus in the absence of hearing loss, it measures acuity in the presence of tinnitus. 
51	In effect the Panel’s reasons concluded that when audiological testing increased the intensity, or decibels, to remove the effects of hearing loss at particular frequencies, the speech discrimination scores also became normal. This conclusion demonstrates that impairment of speech discrimination from tinnitus was, under those conditions, accounted for by the pure tone audiogram. Rather than assessing the effect of tinnitus in the absence of hearing loss, the pure tone audiogram allowed the assessor to determine the extent to which the loss of hearing and the interference in hearing from the presence of tinnitus overlapped. 
52	The Panel then looked at difficulty with elevated sound (presumably elevated in the context of levels of hearing loss that have been established) and in quiet situations to ascertain whether tinnitus had an effect on the ability to hear that was independent of, or additional to, that contributing to the measured level of hearing loss. 
53	The Court of Appeal was careful to say that its interpretation of the ASOHNS Guidelines did not involve any duplication in the assessment of loss, but provided for an aggregation of losses as permitted by the NAL Procedure and the AMA Guides’ tinnitus paragraphs. 
54	To form a view as to the impact of tinnitus upon the function of the ear without regard to the tests that measure the loss of hearing, would not be to assess tinnitus in the presence of bilateral hearing loss. Rather it would be an assessment conducted independent of, and therefore possibly duplicate, the contribution of tinnitus to diminution of hearing. 
55	I have no doubt that the condition of tinnitus can cause a significant impact upon the daily life of those suffering from the condition. Depending on its severity, it may be a source of minor inconvenience or a constant distressing intrusion. However, the AMA Guides and the ASOHNS Guidelines limit the assessment of ENT impairment to that of the hearing function of the ears, and do not include any assessment of other impacts under the Chapter 9 of the AMA Guides. 
56	As can be seen from the previous paragraphs, I have come to a similar conclusion to O’Meara J regarding the assessment of tinnitus under the AMA Guides. Like his Honour, I have concluded that the additional impairment that might arise from tinnitus in the presence of hearing loss, takes account of the findings on pure tone audiogram, and is considered with regard to the testing that is performed to otherwise calculate the measurable aspects of the diminution of hearing. An additional impairment may be added by the assessor when the amplification used to correct hearing acuity does not adequately address the effects of tinnitus upon speech discrimination. There is, in my view, no error in the Panel’s conclusion: 
The panel therefore concluded that the residual tinnitus, which was still present, did not affect discrimination. The Panel finally concluded that there was an impairment percentage of 0% for the effect of tinnitus as the condition does not interfere with the function of the ear and does not impair speech discrimination.
57	As the Panel points out, there is no known treatment for tinnitus and no test that could act as a prosthesis for such a condition. Amplification in audiological testing, used to correct for hearing acuity might be considered similar to fitting a prosthesis for hearing loss, but does not correct for the effects of tinnitus. Those effects might mean speech discrimination is not affected by tinnitus once the speech can be heard, or it might require an additional allowance. Both options consider the effect in the presence of hearing loss. Ground 2 is not made out.
58	Finally, ground 1A addressed specific aspects of the reasons provided by the Panel. The report of the audiologist Mr Watson tested only using the air conduction method. It appears he did so on the basis of his opinion that air conduction thresholds best represent the worker’s noise induced hearing loss. Although the report states it is an assessment in accordance with the ASOHNS Guidelines, it is on its face, not in conformity with item 4 which mandates testing using as a minimum both air and bone conduction methods. Further Mr Watson is an audiologist and it is unclear whether he holds an approval from the Minister to assess binaural loss of hearing under s 63(a)(i) of the WIRC Act. There is nothing obliging the Panel to explain why it disagreed with another practitioner’s assessment. An assessment that on its face is not by a qualified assessor and not in conformity with ASOHNS Guidelines would be additional reasons why the Panel might not have seen fit address that particular opinion. 
59	As to the argument that the Panel was obliged to explain why it selected the particular findings or one or other assessment method, and ‘which of those methods were reliable’, I reject the submission. This submission assumes that one of the two methods was not reliable. This, for reasons explained earlier, is an incorrect assumption. Whilst it is not necessary to consider what reasons might be required where there is a conclusion reached that one method is in whole or in part not reliable, it is not necessary to explain why both results are reliable when the lowest one is selected because, in these circumstances, the lowest (least hearing loss) result must be used. An explanation of why it is the lowest reading disclosed on the audiogram is not required to determine whether error is present. Ground 1A is not made out. 
60	The proceeding will be dismissed. I will hear from the parties as to the form of orders. 

H	Annexure A