ISS Property Services Pty Ltd v O'Brien

DETERMINATION OF APPEAL PANEL
CITATION:	ISS Property Services Pty Ltd v O'Brien [2022] NSWPICMP 514
APPELLANT:	ISS Property Services Pty Ltd
RESPONDENT:	Nathan Wayne O’Brien
Appeal Panel
MEMBER:	Brett Batchelor
MEDICAL ASSESSOR:	Michael Hong
MEDICAL ASSESSOR:	Nicholas Glozier
DATE OF DECISION:	14 December 2022
CATCHWORDS:	wORKERS cOMPENSATION- Appeal by employer against Medical Assessment Certificate (MAC) on the grounds of  the assessment having been made on the basis of incorrect criteria and that the MAC contains a demonstrable error; section 327(3)(c) and (d) of the Workplace Injury Management and Workers Compensation Act 1998 (1998 Act); the respondent worker had previously been assessed as having sustained 24% whole person impairment (WPI) as a result of psychological injury arising out of or in the course of his employment with the NSW Police Force for which he had been compensated, and also settled a damages claim against the NSW Police Force in respect of such injury; the Medical Assessor (MA) in the current proceedings assessed 17% WPI as a result of psychological injury arising out of or in the course of employment with the appellant, and deducted one tenth therefrom pursuant to section 323 of the 1998 Act, for a final WPI of 15%; the appellant submitted that the MA had not complied with section 323(2) of the 1998 Act in making such deduction, and that, having regard to the evidence before him, the deduction should have been higher than the one tenth provided for in that subsection; Held – the Appeal Panel accepted that submission, and that the section 323 of the 1998 Act deduction should be 25% of the 17% WPI assessed by the MA; MAC dated 29 July 2022 revoked and new certificate issued.

BACKGROUND TO THE APPLICATION TO APPEAL

On 23 September 2022 ISS Property Services Pty Ltd (the appellant/ISS) lodged an Application to Appeal Against the Decision of a Medical Assessor. The medical dispute was assessed by Douglas Andrews (the MA/MA Andrews), a Medical Assessor, who issued a Medical Assessment Certificate (MAC) on 29 July 2022.
The appellant relies on the following grounds of appeal under s 327(3) of the Workplace Injury Management and Workers Compensation Act 1998 (1998 Act):
· the assessment was made on the basis of incorrect criteria,
· the MAC contains a demonstrable error.
The delegate is satisfied that, on the face of the application, at least one ground of appeal has been made out. The Appeal Panel (the Panel) has conducted a review of the original medical assessment but limited to the ground(s) of appeal on which the appeal is made.
The Personal Injury Commission Rules 2021 (the PIC Rules), and Procedural Direction PIC7 – Appeals, reviews, reconsiderations and correction of obvious errors in medical disputes set out the practice and procedure in relation to the medical appeal process under s 328 of the 1998 Act. An Appeal Panel determines its own procedures in accordance with the PIC Rules.
The assessment of permanent impairment is conducted in accordance with the NSW Workers Compensation Guidelines for the Evaluation of Permanent Impairment, 4th ed, reissued 1 March 2021 (the Guidelines) and the American Medical Association Guides to the Evaluation of Permanent Impairment, 5th ed (AMA 5).

RELEVANT FACTUAL BACKGROUND

Nathan Wayne O’Brien (the respondent/Mr O’Brien) started work as a cleaner with the appellant at the Lismore College of TAFE on 17 August 2018, initially as a casual employee, transitioning to permanent part time in November 2019. He worked from 5.00am to 10.00am, Monday to Friday, carrying out all the usual duties of a college cleaner. He was able to perform these duties. During COVID, Mr O’Brien worked an extra two and a half hours a week until a replacement was found to carry out these extra hours.
The respondent found the workplace difficult to cope with, experiencing interpersonal conflicts with other employees, due in part to the fact that he was an ex-policeman. He was bullied by another employee, and felt targeted and harassed by other employees, some of whom were aggressive in their approach to him. These problems persisted, notwithstanding Mr O’Brien raising his concerns with his managers.
Mr O’Brien sought treatment from his general practitioner and was referred to Dr Mark Scurrah, psychiatrist, who he had seen previously for treatment of post-traumatic stress disorder arising from his employment as a police officer.
The respondent left his job with ISS on 10 August 2020 and has not worked since then.
The respondent was diagnosed with, post-traumatic stress disorder major depressive disorder and alcohol use disorder in 2009. He was medically discharged from the NSW Police Force in August 2010 and subsequently was assessed as having suffered 24% whole person impairment (WPI) as a result of injury sustained in the course of his employment as a police officer.
In November 2016 Mr O’Brien settled a negligence claim against the NSW Police Force for the sum of $537,500.
Mr O’Brien claims that by 2017, when he recommenced employment, he had symptomatically recovered from the severe presenting symptoms of post-traumatic stress disorder and depression from which he suffered between 2009 and 2016.

PRELIMINARY REVIEW

The Panel conducted a preliminary review of the original medical assessment in the absence of the parties.
As a result of that preliminary review, the Panel determined that it was not necessary for the worker to undergo a further medical examination because neither the appellant nor the respondent sought such further medical examination, and the Panel considers that there is sufficient material in the Appeal Papers (AP) on which to base its decision.

EVIDENCE

Documentary evidence

The Panel has before it all the documents that were sent to the MA for the original medical assessment and has taken them into account in making this determination.

Medical Assessment Certificate

The parts of the medical certificate given by the MA that are relevant to the appeal are set out, where relevant, in the body of this decision.

SUBMISSIONS

Both parties made written submissions. They are not repeated in full, but have been considered by the Panel.

Appellant

In summary, the appellant submits that the MA fell into error as defined by s 327(3)(c) and (d) with respect to the deduction applied pursuant to that section of the 1998 Act. The appellant relies upon the following specific errors:
(a)    the MA applied the incorrect test for calculating a deduction under s 323;
(b)    the MA failed to have regard to critical evidence with respect to the pre-existing condition;
(c)    the MA placed improper weight upon the worker’s lay observations as to his functioning prior to the injury, and
(d)    the deduction of one-tenth made by the MA is at odds with (not consistent with or supported by) the evidence and should be revoked, with a greater deduction substituted.
The appellant submits that the MA diagnosed the respondent as suffering from the following three psychological conditions:
(a)    post-traumatic stress disorder;
(b)    major depressive disorder, and
(c)    alcohol use disorder.
The appellant notes that the MA assessed the respondent as suffering from 17% WPI due to these injuries/conditions, then determined to apply a one-tenth deduction under s 323 of the 1998 Act to account for the pre-existing psychological injury, abnormality or condition suffered by the respondent.
The appellant notes that it is not in dispute that the respondent suffered a significant pre-existing injury, abnormality or condition.
The appellant submits that the MA made various references to the respondent’s pre-existing psychological condition throughout the MAC, and notes his following relevant comments:
(a)    the MA noted the worker was diagnosed with post-traumatic stress disorder, major depressive disorder and alcohol use disorder in 2009 and he received compensation in respect of a 24% WPI (in connection with this claim against the NSW Police). The MA correctly noted that the worker settled a negligence claim against the NSW Police Force in November 2016 in the sum of $537,500;
(b)    the MA noted that the worker had “longstanding” mental health problems relating to his time with the NSW Police Force;
(c)    the MA then noted that the worker had a “long history of PTSD, major depression and alcohol use disorder,” and stated that even if the worker had recovered in 2017, his current conditions are “a relapse into illness” and he has “many symptoms of PTSD”. The MA noted that without the pre-existing condition, the worker’s condition “would be less severe”, and
(d)    the MA then noted that there is evidence the worker symptomatically and functionally improved after 2016. Critically, the MA then stated:
“there is no evidence that Mr O’Brien was not functioning well during 2017 or early 2018 so a 1/10^th deduction is warranted”. (Emphasis in submissions.)
The appellant then summarises evidence in the AP which it submits outlines the true nature and extent of the pre-existing psychological injury/condition suffered by the respondent. Relevant parts of such evidence will be referred to hereunder.
The appellant submits that the assessment of the s 323 deduction applied by the MA was patently contrary to, and against the weight of, the evidence which supports a far greater contribution made by the pre-existing injury/condition to the impairment now assessed.
The appellant submits that the MAC discloses that the respondent put forward his own lay view to the MA with respect to the state of his condition prior to commencing work with ISS. Importantly on page three of the MAC[1] the appellant notes the MA’s statement that the respondent described “symptomatically recovering and recommencing employment in 2017.” (Emphasis in submissions.)
[1] AP p 17.
The appellant cites on the following further comments of the respondent, recorded by the MA:
(a) that he “went into remission” in late 2016 or early 2017 and was able to return to work, and
(b) “argues that he fully recovered from his PTSD and major depression in late 2016…”;[2]
and the MA’s comment that it was “surprising” that the respondent fully recovered after such severe mental health issues between 2009 and 2016. The appellant submits that it is apparent that the MA placed at least some weight of the respondent’s assertions in this regard. The appellant repeats the comment of the MA referred to in [22(d)] above.[3]
[2] AP pp 20-21.
[3] AP p 23.
The appellant submits that the MA has not stated on what basis a one-tenth deduction has been calculated, and that he does not address the specific test posed by s 323(2), which requires that the exact extent of the deduction be too difficult or costly to determine, and that the assessment is at odds with the evidence.
The appellant submits that to the extent that the MA did rely upon s 323(2) of the 1998 Act, neither of the criteria provided under that subsection are satisfied. This case, unlike most cases, could not have been one where the exact deduction was too costly to determine. The respondent quite clearly has a lengthy past psychological history documented in detail in the reports of the treating and qualified doctors, and the respondent has been assessed under a previous workers compensation claim by an Approved Medical Specialist as suffering 24% WPI as a result of his injuries.
Whilst it is not asserted by the appellant that an assessment of impairment provided at one point in time will remain that degree indefinitely, it submits that it is patently illogical, and with respect unreasonable, to conclude that a one-tenth deduction represents the full extent of the contribution of the respondent’s-existing condition in the circumstance where a previous assessment provided 24% WPI.
The appellant also submits that the MA has applied the incorrect test.
The appellant submits that it is apparent from the comments on p 9 of the MAC that the MA calculated the one-tenth deduction on the basis of his comment that “There was no evidence that Mr O’Brien was not functioning well during 2017 or early 2018, so one-tenth deduction is warranted”. It is a reasonable inference from that statement that the MA placed undue weight on the absence of symptoms (that is, the applicant was “functioning well”) in calculating that deduction.
The appellant submits that the focus on the respondent being symptomatic is contrary to law, citing in support thereof Vitaz v Westform (NSW) Pty Ltd.[4]
[4] [2011] NSWCA 254.
The appellant submits that, notwithstanding cl 11.10 of the Guidelines, which does suggest a focus on the symptomatic effects insofar as they may affect a worker’s function, it was held in Marks v Secretary, Department of Communities and Justice (No 2)[5], that that Guideline is invalid to the extent it requires exclusive focus on the presence of symptoms.
[5] NSWSC 616 at 29 (Marks (No 2)).
The appellant submits that the starting point in the enquiry as to the s 323 deduction is consideration of the precise nature of the pre-existing condition. The MA confirmed that the pre-existing condition, resulting from injuries sustained in the course of employment with the NSW Police Force, was post-traumatic stress disorder, major depressive disorder and alcohol use disorder.[6] Critically the appellant submits, these are the exact same conditions confirmed by the MA as the current diagnosis. The appellant therefore submits accordingly that it is apparent that the respondent is suffering from persisting effects of injury suffered in the course of his employment with the NSW Police Force. The evidence outlining the extent of the respondent’s pre-existing condition is clearly set out in the documentation before the MA. Mr O’Brien was suffering from these three conditions from at least 2009 as a result of injury sustained on the course of his employment with the NSW Police Force.
[6] AP p 17.
The appellant submits that the evidence from treating practitioners confirms ongoing significant symptoms over many years up to at least 2015-2016, and that as of May 2016 Mr O’Brien was asserting significant ongoing effects from the injury. This is apparent from the Statement of Claim in proceedings taken by him against the NSW Police Force. Clinical notes from the general practitioner also reveal an attendance in 2017 for post-traumatic stress disorder and consideration of a mental health care plan, which does not support any conclusion that the effects of the prior condition had abated by that time.
The appellant submits that the conclusion that the respondent was “functioning well” as at 2017 is inconsistent with the objective evidence including Mr O’Brien’s own statement of claim in which he asserted ongoing total incapacity, requirement for treatment and a multitude of psychological symptoms persisting at least as of May 2016. Mr O’Brien remained absent from work for a period of at least seven years as a result of persisting and pervasive psychological injury.
The appellant acknowledges that Dr Miller, the qualified expert on which it relies, in her report dated 3 October 2021[7] also ascribed a one-tenth deduction. It submits however that such conclusion must be viewed in the context of the doctor’s opinion that the entirety of the condition with which the respondent presented to Dr Miller was directly related to his employment/injury with the NSW Police Force, and not the result of any discrete injuries sustained with ISS. The injury under consideration is in respect of the period of employment with ISS only, and accordingly any impairment predating 2018 constitutes a pre-existing condition for the purposes of s 323, which was not the basis upon which Dr Miller provided her assessment.
[7] AP p 515.
The appellant submits that the MA was in error in applying the one tenth assessment under s 323 of the 1998 Act.
The appellant submits that the MAC should be revoked, and a greater deduction applied pursuant to s 323.

Respondent

In reply, the respondent submits that the appellant fails to appreciate that:
(a)    the examination by the MA was taken at a different time to the other doctors;
(b)    the MA based his decision on his examination and the evidence at hand, and
(c)    the evaluation and assessment, based on the history and examination, was purely a matter for him.
The respondent submits that, reading the MAC as a whole, it is clear that the MA properly undertook his task in the assessment, and that the appeal must be dismissed.
The respondent sets out “Outline & Principles”[8] in his submissions, citing the following:
(a)    the “gatekeeper” role of the Registrar [sic, President] in determining the current application[9];
(b)    in undertaking that process the decision maker’s reasons are not to be overzealously scrutinized by seeking to discern whether some inadequacy may be gleaned from the way in which reasons are expressed[10];
(c)    that a demonstrable error requires the appellant to demonstrate to the Registrar [sic, President] that there is an arguable case of error appearing on the face of the MAC, which may be an error of fact or law. It must be more than one that depends on evidence that is not within s 327(a) or (b) of the 1998 Act being adduced in the appeal [11];
(d)    the expression “incorrect criteria” is undefined in the 1998 Act, and that Wood CJ at CL in Campbelltown City Council v Vegan[12] referred to a statement in the minister’s Second Reading speech to the effect that s 327(3)(c) was designed to cover circumstances where Workcover Guides themselves had been incorrectly applied, and
(e)    the Court of Appeal (Basten JA, McColl JA agreeing) in Campbelltown City Council v Vegan[13] said that, while it was arguable that factual errors made by an approved medical specialist, as recorded in the Certificate, may be “demonstrable errors” within s 327(3)(d), they would not usually satisfy the “incorrect criteria” ground.
[8] AP p 29.
[9] Ballas v Department of Education (State of New South Wales) [2020 NSWCA 89.
[10] Minister for Immigration and Ethnic Affairs v Wu Shan Liang (1996) 185 CLR 259 at [271-272], and Bojko v ICM Property Service Pty Ltd [2009] NSWCA 175 (Bojko).
[11] Merza v Registrar of the Workers Compensation Commission [2006] NSWSC 939 at [39], and Haroun v Rail Corporation NSW [2008] NSWSC 160.
[12] [2004] NSWSC 1189 at [59].
[13] [2006] NSWCA 284 (Vegan).
The respondent submits that the submissions of the appellant that:
(a) the MA failed to engage with the documentary evidence and/or preferred the respondent’s evidence to the documentary evidence, and
(b) this led to the MA committing an error in relation to the deduction pursuant to s 323,
cannot be accepted. The respondent notes that the MA conducted a 70 minute interview with Mr O’Brien in which he gave a “cogent account [although] struggled with some details and sequence of events” (emphasis in submissions). The respondent also submits that the MA reviewed the extensive documentary evidence, as is evident from comments throughout the report. Aspects of the evidence in Parts 7, 8, 10 and 11 of the MAC are referred to. The respondent submits that the MA carefully balanced what he said with the documentary evidence. The MA did not just accept what he said.
The respondent submits that the appellant cannot point to any evidence to contradict the recording by the MA in the MAC that Mr O’Brien had symptomatically and functionally improved after 2016, noting that he was engaged with family and friends and worked more than 20 hours a week during 2017 and 2018 before starting work with ISS. The respondent submits that historical evidence says nothing about the way he was functioning at the time of the incident.
The respondent submits that selective use of historical material is “simply wrong”, and such use cannot be preferred over evidence dealing with the topic. Reference is then made to the evidence of Dr Sugden, Dr Scurrah and Dr Miller.

The respondent submits that the appellant’s submissions seek to undermine the importance of the evaluative exercise placed on the MA.
The respondent submits that the failure of the MA to mention a particular document does not equate to a failure to consider it[14]. The MA was not required to consider, much less cite, every document that was in existence. He was only required to cite those that established the pathway to his reasoning process.
[14] Golijan v Motor Accidents Authority [2012] NSWSC 1106.
The respondent rejects that appellant’s submission that the MA applied the wrong test pursuant to s 323 and/or did not explain how he reached that conclusion in applying that test. He submits that it is perfectly obvious that the MA was aware of s 323 and engaged with it. His reasons are sufficient to disclose the reasoning process.
The respondent notes that, in circumstances in which both experts agreed that the appropriate deduction was 10%, it is a little difficult to see what else the MA was required to do. The appeal should be dismissed.

FINDINGS AND REASONS

The procedures on appeal are contained in s 328 of the 1998 Act. The appeal is to be by way of review of the original medical assessment but the review is limited to the grounds of appeal on which the appeal is made. An Appeal Panel is limited to determining error as alleged by the appellant, but must assess in accordance with the Guidelines. Once error is made out, the Panel may “review” the MAC. Relevant case law includes Siddik v Workcover Authority of NSW[15] and NSW Police Force v Registrar[16].
[15] [2008] NSWCA 116.
[16] [2013] NSWSC 1792.
In Vegan the Court of Appeal held that the Appeal Panel is obliged to give reasons. Where there are disputes of fact it may be necessary to refer to evidence or other material on which findings are based, but the extent to which this is necessary will vary from case to case. Where more than one conclusion is open, it will be necessary to explain why one conclusion is preferred. On the other hand, the reasons need not be extensive or provide a detailed explanation of the criteria applied by the medical professionals in reaching a professional judgement.
The appellant relies on what Simpson AJ decided in Marks No 2 in respect of cl 11.10 of the Guidelines, which is in the following terms:
“To measure the impairment caused by a work-related injury or incident, the psychiatrist must measure the proportion of WPI due to a pre-existing condition. Pre-existing impairment is calculated using the same method for calculating current impairment levels. The assessing psychiatrist uses all available information to rate the injured worker’s pre-injury level of functioning in each of the areas of function. The percentage impairment is calculated using the aggregate score and median class score using the conversion table below. The injured worker’s current level of WPI % is then assessed, and the pre-existing WPI % is subtracted from their current level, to obtain the percentage of permanent impairment directly attributable to the work-related injury. If the percentage of pre-existing impairment cannot be assessed, the deduction is 1/10^th of the assessed WPI.”
Her Honour held that, to the extent that cl 11.10 requires exclusive focus on the presence of pre-existing symptoms in respect of a psychological injury which was in issue in that case, it is inconsistent with the requirements of s 323(1) of the 1998 Act. Her Honour said at [15]-[21]:
“15.   The plaintiff’s submissions denying inconsistency between s 323(1) and Guideline 11.10 avoided the real issues. It was contended (correctly) that it is not every case in which a pre-existing condition can be identified that will result in a deduction under s 323(1). It is always a matter for assessment whether any proportion of the impairment assessed is due to such a pre-existing condition. So much is uncontroversial and has long been recognised: see Matthew Hall Pty Ltd v Smart [2000] NSWCA 284; (2000) 21 NSWCCR 34; Cole v Wenaline Pty Ltd [2010] NSWSC 78; Vitaz v Westform (NSW) Pty Ltd [2011] NSWCA 254; Ryder v Sundance Bakehouse [2015] NSWSC 526.
16.   The more important question, which the plaintiff’s submissions did not address, is whether a pre-existing condition, notwithstanding that it is asymptomatic at the time of the injury in respect of which the assessment is undertaken, may, nevertheless, contribute to the degree of impairment. In respect of physical injuries, it has long been held that it can: Government Cleaning Service v Ellul (1996) 13 NSWCCR 344; Matthew Hall Pty Ltd v Smart [2000] NSWCA 284; (2000) 21 NSWCCR 34; Elcheikh v Diamond Formwork (NSW) Pty Ltd (In Liquidation) [2013] NSWSC 365 at [91] and [95].
17.   In the light of this consistent line of authority, s 323(1) must be construed as requiring deduction from the assessment of the degree of permanent impairment of any proportion of the impairment that is due to ‘previous injury … or … pre-existing condition or abnormality’ whether or not the pre-existing condition or abnormality is symptomatic at the time of injury. As noted in the preliminary reasons, the cases which have previously considered this question all related to physical injury. However, as was observed on behalf of the first defendant, s 323(1) does not distinguish between physical and psychiatric or psychological injuries. It applies to all injuries equally.
18.   Guideline 11.10, with its focus on ‘pre-injury level of functioning’, does not allow for deduction from the assessment of impairment in cases where an asymptomatic pre-existing condition contributes to the degree of permanent impairment assessed. To the extent that Guideline 11.10 excludes consideration of any contribution to the permanent impairment that might be made by an asymptomatic pre-existing condition, it is inconsistent with s 323(1).
19. Moreover, if it were to be accepted, as was asserted on behalf of the plaintiff in submissions in reply, that Guideline 11.10 determines that an asymptomatic condition does not materially contribute to the subsequent condition, or, as is asserted in the relevant paragraphs of those submissions (extracted at [13] above), does not do so unless it was causing ‘an assessable impairment’ prior to the injury in respect of which the assessment is made, the conclusion that Guideline 11.10 is in conflict with s 323(1) is reinforced. As was submitted on behalf of the first defendant, s 323(1) makes no distinction between physical and psychiatric/psychological injury. There may be good reason to issue, in respect of the latter, a guideline that prescribes a different procedure from a guideline with respect to the former. But that can be done only in conformity with the legislation. There is nothing in s 323(1) that authorises exclusion of asymptomatic pre-existing conditions as causative or partially causative of a subsequent impairment.
20.   On the assumption that the authorities identified in [16] above were correctly decided (and it has not been suggested that they were not), the same reasoning must apply to psychiatric/psychological injury.
21.   It is quite true, as the plaintiff insisted, that not every pre-existing condition will be a contributing cause of the permanent impairment. But that is a different question.”
The factual background to Marks No 2 is set out by her Honour at [3]-[5] and summarised as follows.
The plaintiff worker claimed, under s 66 of the 1987 Act, compensation for permanent impairment arising out of a workplace injury whilst employed by the first defendant, the employer. The injury was psychiatric, liability for which was accepted by the first defendant. The matter was referred for assessment by an Approved Medical Specialist (AMS) who assessed the plaintiff as having sustained 21% WPI, made up of a then current impairment of 19% and an increment of 2% representing the benefits of treatment the plaintiff had received. A MAC was issued to that effect, which was confirmed by the AMS in a further MAC issued after reconsideration of the earlier MAC. Although he was aware that the plaintiff had previously suffered post-traumatic stress disorder, the AMS expressly found that there was ‘no evidence to suggest the experience of psychiatric disturbance or receipt of psychiatric treatment in the years preceding’ the workplace injury in respect of which the assessment was conducted. The AMS thus treated the plaintiff as having been asymptomatic prior to the events that gave rise to the psychiatric injury.
Pursuant to s 327 of the 1998 Act the plaintiff’s employer, the first defendant, appealed to an Appeal Panel. The Appeal Panel revoked the (second) MAC issued by the AMS and certified, by way of substitution, that the plaintiff’s degree of permanent impairment caused by the workplace injury was 14%. It did this because, while agreeing with the AMS that the plaintiff’s then current impairment was 19%, it considered that part of that impairment was due to a pre-existing, though at the time of injury asymptomatic, condition from which the plaintiff suffered (that being the effects of the previous post-traumatic stress disorder, or vulnerability of the plaintiff to subsequent psychiatric injury by reason of that condition). The Appeal Panel also revoked the increment of 2% allowed by the AMS for ‘the treatment effect’.
The plaintiff worker submitted that cl 11.10 of the Guidelines required a determination that an asymptomatic condition does not materially contribute to the subsequent condition, or that such condition does not do so unless it was causing ‘an assessable impairment’ prior to the injury in respect of which the assessment is made. The result is that Guideline 11.10 is in conflict with s 323(1), and must be followed. Her Honour did not accept this submission, holding at least in respect of a psychiatric injury, it was invalid and that the requirement of s 323(1) of the 1998 Act must prevail.
It is axiomatic that each case depends on its own facts, and the facts in Marks No 2 differed from those under consideration in this matter. In that case there was no previous psychiatric injury in respect of which there had been a finding of permanent impairment as occurred in this case, with the assessment of 24% WPI as a result of injury sustained by Mr O’Brien arising out of or in the course of his employment with the NSW Police Force. Nevertheless, the principle is the same. The fact that Mr O’Brien was, or may have been, asymptomatic, in the years leading up to the injury sustained in the course of his employment with ISS does not mean that there should be no deduction pursuant to s 323(1) of the 1998 Act, or more relevantly, that any such deduction should be the one-tenth referred to in s 323(2).
The MA recorded in the MAC the history of the post-traumatic stress disorder, major depressive disorder and alcohol use disorder with which Mr O’Brien was diagnosed on 2009 resulting from his service with the NSW Police Force. He was discharged from the Force in August 2010. On 30 November 2011 a Medical Appeal Panel determined that Mr O’Brien had sustained 24% WPI as a result of psychological injury sustained arising out of or in the course of his employment in the NSW Police Force[17], for which he was compensated.
[17] AP p 836.
On 3 May 2016 the respondent commenced proceedings against the NSW Police Force which were settled for the sum of $537,500 inclusive of costs and clear of workers compensation payments to date by way of a Deed of Release dated 22 November 2016.[18]
[18] AP p 870.
The disabilities suffered by the respondent as a consequence of injuries sustained, extracted from the Statement of Claim commencing the proceedings in the District Court of NSW, are set out in full in the MAC.[19]
[19] AP p 17.
The appellant in its submissions has set out in some detail the treatment received by Mr O’Brien over the period from March 2014 to July 2017 from Dr Michael du Sautoy, psychologist, Dr Michael Scurrah, psychiatrist and doctors at the Lennox Head Medical Centre. There are also Certificates of Capacity covering the period from 25 August 2015 to 29 August 2016 containing diagnoses of depression and post-traumatic stress disorder as well as reference to physical injuries.[20] As of 9 May 2016 the respondent’s treating psychiatrist, Dr Scurrah, recorded that the respondent’s post-traumatic stress disorder remained chronic, and that depression was in remission.[21] On 11 July 2017 the respondent consulted his general practitioner for post-traumatic stress disorder and a mental health care plan was under consideration.[22]
[20] AP pp 11-12, and pp 640-654.
[21] AP p 804.
[22] AP p 748.
The respondent first presented to Dr Sugden on 23 August 2019 regarding reported psychological injury with ISS.[23] Dr Sugden reported that Mr O’Brien was suffering from adjustment disorder with anxiety/depressed mood, and a history of post-traumatic stress disorder and depression that had been stable for many years “…prior to this” (presumably referring to the current injury).
[23] AP p 220.
The respondent saw Dr Scurrah again over the period from 4 November 2020 to 8 February 2021.[24] The doctor recorded that Mr O’Brien attributed his then current symptoms (consistent with chronic depressive disorder with anxiety symptoms and the alcohol abuse) to workplace stressors at ISS. He advised that he initially began self-medicating his ISS work related symptoms with excess alcohol. Dr Scurrah said that at the time of his report, the chronic depressive disorder with anxiety symptoms had partially improved with treatment, but not entered complete remission. The alcohol abuse was in remission.
[24] Report dated 9 April 2021, AP p 228.
In answer to a specific question [3] in the report dated 9 April 2021 Dr Scurrah was asked if the respondent’s current psychiatric/psychological condition diagnosed by him related in any way to the previous diagnosis of post-traumatic stress disorder. He said in reply:
“I note your question asked ‘related in any way to the previous diagnosis of PTSD’.
This is a highly complex question. At a simplistic level, a prior history of PTSD (and/or Depression and/or Alcohol Abuse) makes you subsequently at heightened risk of developing those types of conditions again. The risk cannot be easily quantified/qualified due to numerous variables.”
Dr Ash Takyar saw the respondent on 19 July 2021 at the request of his solicitor and produced reports dated 12 August 2021 (x2).[25] Dr Takyar diagnosed Mr O’Brien as presenting with an adjustment disorder with mixed anxiety and depression (chronic) related to the injury suffered while at ISS. In respect of the deduction pursuant to s 323, Dr Takyar said in his second report “… - a section 323 deduction has been applied because of Mr O’Brien’s pre-existing symptoms from his post-traumatic stress disorder.” No other explanation was provided.
[25] AP pp 208 and 217.
Dr Takyar disagreed with the diagnosis of Dr Miller, who independently medically examined the respondent via Telehealth on 15 October 2020 at the request of ISS and produced a report dated 3 November 2020.[26] Dr Miller examined the respondent again via Telehealth on 1 October 2021 and produced a further report dated 3 October 2021.[27]
[26] AP p 502.
[27] AP p 515.
In her first report Dr Miller diagnosed Mr O’Brien as suffering from alcohol use disorder, which she said was “…not a compensable, work-related psychiatric injury as defined by DSM-V or ICD 10”, and that he was not suffering from a reoccurrence of his post-traumatic stress disorder. She said that he was experiencing emotional upset in the context of workplace interpersonal conflict.
In her second report, Dr Miller referred to the diagnosis of Dr Takyar, noting his disagreement with her diagnosis of alcohol use disorder, and his report that Mr O’Brien ceased alcohol consumption in November or December 2020. Dr Miller noted that she saw the respondent on 15 October 2020, ten months prior to Dr Takyar’s assessment and hence, even though Mr O’Brien had abstained from alcohol at that time, the correct diagnosis would be alcohol use disorder, in partial remission. She said that the fact that consumption of alcohol had ceased does not mean that that part of the respondent’s history is erased.
On 1 October 2021 Dr Miller diagnosed the respondent as suffering from adjustment disorder, with depressed mood, and alcohol use disorder, in partial remission. She said:
“It is my opinion that Mr O'Brien's current Adjustment Disorder, with depressed mood, has not been caused by his employment with ISS and nor has his Alcohol Use Disorder, which is now in partial remission. It is my opinion that Mr O’Brien’s Adjustment Disorder, with depressed mood, has occurred as a result of his underlying personality vulnerability, which itself is causally related to the traumatic events he experienced whilst in the Police Force, which in turn, has had an adverse impact on his resilience.”
Dr Miller assessed the respondent as suffering from 11% WPI less one tenth thereof (1.1%), plus a treatment uplift of 1%, for a final impairment of 11% WPI. This assessment must be viewed in the context of, as submitted by the appellant and referred to at [37] above, Dr Miller says that the entirety of the condition with which the respondent presented was directly related to his employment/injury with the NSW Police Force, and not the result of any discrete injuries sustained with ISS. The s 323 deduction of one-tenth adopted by Dr Miller is not of great assistance to the Panel in assessing, what should be the s 323 deduction from the assessment of the MA of 17% WPI as a result of the psychological injury arising out of or in the course of Mr O’Brien’s employment with ISS. Dr Miller’s opinion as to the causation of the respondent’s psychological condition is however some evidence of a significant pre-existing condition.
The following comments of the MA in the MAC are in the opinion of the Panel relevant to the determination of the s 323 deduction.
The “summary of injuries and diagnoses” at [7.] of the MAC is:
“My diagnoses rely on the Diagnostic and Statistical Manual – Fifth Edition (DSM-5),
published by the American Psychiatric Association.
o persistent depressive disorder with anxious distress
o alcohol use disorder in remission
o PTSD in partial remission
Mr O'Brien has long-standing mental health problems relating to his time with the NSWPF. He states that he went into remission late in 2016 or early 2017 and was able to return to work.”
In respect of consistency of presentation, Medical Assessor Andrews says:
“Mr O'Brien argues that he fully recovered from his PTSD and major depression in late 2016 or early 2017. He had severe mental health issues from at least 2009 until 2016. It is surprising that that he then fully recovered in 2017 with no residual impairment.”
At [8.e.] of the MAC under “Evaluation of Permanent Impairment”, when asked if any proportion of loss of efficient use or impairment or WPI was due to a previous injury, pre-existing condition or abnormality, Medical Assessor Andrews says:
“Yes. Mr O'Brien has a long history of PTSD, major depression and alcohol use disorder. Even if he fully recovered in 2017, his current conditions are a relapse into illness. He has many symptoms of PTSD, including emotional dysregulation, cognitive distortions, alteration in arousal and reactivity, hypervigilance and avoidance. He also has symptoms across the mood spectrum. Without the pre-existing condition, Mr O’Brien’s condition and impairment would be less severe.”
In giving an explanation of his calculations under “REASONS FOR ASSESSMENT” at [10.b.] of the MAC, Medical Assessor Andrews says:
“I determined a 17% WPI before deducting one-tenth for the pre-existing condition (1.7% WPI, arriving at a final 15% WPI after rounding.
I do not adjust for the effect of treatment because there has not been a substantial or complete elimination of impairment with treatment”
At [11.b.] of the MAC when asked as to matters which were taken into account in respect of the contribution of the previous injury, pre-existing condition or abnormality to the assessment of WPI that results from injury, Medical Assessor Andrews says:
“There is evidence that Mr “O’Brien had symptomatically and functionally improved after 2016. He states that he was engaged with family and friends and worked more than 20 hours a week during 2017 and 2018 before starting work with ISS property.
However, he had a prolonged period of severe mental illness which was prone to relapse with increasing stress, such as he experienced in the workplace at ISS Property. This represents more than a vulnerability and the pre-existing illness significantly contributed to the symptoms and impairment severity subsequently.
There is no evidence that Mr O’Brien was not functioning well during 2017 and early 2018, so a one-tenth deduction is warranted.”

At [11.c.] Medical Assessor Andrews says:
“The extent of the deduction is difficult or costly to determine, so in applying the provisions of s.323(2) I assess the deductible proportion as one-tenth.”
(Emphasis in original)
The respondent submits that the appellant cannot point to any evidence to contradict that he had symptomatically and functionally improved after 2016, that he was not functioning well during 2017 and early 2018 and that, contrary to what is submitted by the appellant, Medical Assessor Andrews did not just accept what he said. On the other hand, Medical Assessor Andrews found it “…surprising that that (Mr O’Brien) then fully recovered in 2017 with no residual impairment.” The Panel is of the view that “no residual impairment” is inconsistent with the significant contribution “…to symptoms and impairment severity subsequently” suffered by Mr O’Brien, as recorded by the MA.
The Panel is also of the view that the significant contribution of the pre-existing injury and condition from which the respondent suffered is greater than one-tenth of the 17% WPI assessed by the MA.
The Panel finds that the MA has not explained on what basis the one-tenth deduction was calculated and also, in accordance with s 323(2) of the 1998 Act, why the extent of the deduction is too difficult or costly to determine. There is also no explanation of why it is at odds with the evidence. The Panel is of the view that a one-tenth deduction is at odds with the evidence before the MA, to which he referred in some detail in the MAC.
The Panel therefore finds a demonstrable error in the MAC.
The respondent has suffered a severe psychological injury with very similar psychological symptoms previously, with 24% WPI. His previous psychological injury was protracted and had only remitted, if the respondent’s history is taken at face value, and the Panel notes that on 11 July 2017 the respondent consulted his general practitioner for ongoing post-traumatic stress disorder, for a very short period of time before the subject injury. There is a consensus amongst psychiatrists and psychologists, that post-traumatic stress disorder and depression generally produce greater impairment with each new episode, and the pre-existing asymptomatic injury contributes to his current impairment. The pre-existing injury has more than a minor contribution and a one-tenth deduction would be at odds with the available evidence. The worker continues to have the same disorder, post-traumatic stress disorder, as he did from 2009 to at least 2017. This has been diagnosed as in partial remission, that is, not recovered. The MA records he has many impairing symptoms of post-traumatic stress disorder including his emotional dysregulation, cognitive distortions, alteration in arousal and reactivity, hypervigilance and avoidance The Panel does not believe the appellant’s pre-existing injury has a greater contribution to his current impairment than the subject injury, therefore the Panel assesses the pre-existing contribution at one quarter. This is consistent with the approach taken in Marks (No 2). Having regard to the evidence summarised above and the relevant parts of the MAC referred to, the Panel of the view that pursuant to s 323(1) of the 1998 Act, there should be a deduction of one quarter (25%) due to previous injury, pre-existing condition or abnormality from the degree of WPI of 17% assessed by the MA.
This deduction from 17% WPI of one quarter, results in 13% WPI suffered by the respondent as a result of injury arising out of or in the course of his employment with the appellant.
For these reasons, the Appeal Panel has determined that the MAC issued on 29 July 2022 should be revoked, and a new MAC should be issued. The new certificate is attached to this statement of reasons.

PERSONAL INJURY COMMISSION

APPEAL PANEL

MEDICAL ASSESSMENT CERTIFICATE

Injuries received after 1 January 2002

Matter Number:	W379/22
Applicant:	Nathan O’Brien
Respondent:	ISS Property Services Pty Ltd

This Certificate is issued pursuant to s 328(5) of the Workplace Injury Management and Workers Compensation Act1998.

The Appeal Panel revokes the Medical Assessment Certificate of Dr Douglas Andrews and issues this new Medical Assessment Certificate as to the matters set out in the Table below:

Table - Whole Person Impairment (WPI)

Body Part or system	Date of Injury	Chapter, page and paragraph number in NSW workers compensation guidelines	Chapter, page, paragraph, figure and table numbers in AMA 5 Guides	% WPI	Proportion of permanent impairment due to pre-existing injury, abnormality or condition	Sub-total/s % WPI (after any deductions in column 6)
Psychiatric	10 August 2020 (deemed)	Chapter 11, pp 54-60	n/a	17%	1/4	13%
Total % WPI (the Combined Table values of all sub-totals)					13%

[2022] NSWPICMP 514

14 December 2022