BGW v Constel Pty Ltd

DETERMINATION OF APPEAL PANEL
CITATION:	BGW v Constel Pty Ltd [2023] NSWPICMP 355
APPELLANT:	BGW
RESPONDENT:	Constel Pty Ltd
Appeal Panel
MEMBER:	Marshal Douglas
MEDICAL ASSESSOR:	Graham Blom
MEDICAL ASSESSOR:	Michael Hong
DATE OF DECISION:	26 July 2023
CATCHWORDS:	wORKERS cOMPENSATION - Whether Medical Assessor (MA) erred by making a deduction of 50% under section 323(1) for the proportion of appellant’s permanent impairment due to pre-existing conditions; whether the MA erred by not assuming, under section 323(2), that the deductible proportion was 10%; Appeal Panel found that MA had concluded that making an assumption under section 323(2) that deductible proportion was 10% would be at odds with the evidence and Appeal Panel considered MA was correct to so conclude; Held – Appeal Panel found MA did not err by assessing deductible proportion was 50%; Medical Assessment Certificate upheld.

BACKGROUND TO THE APPLICATION TO APPEAL

On 25 May 2023 BGW, the appellant, lodged an Application to Appeal Against the Decision of a Medical Assessor. The medical dispute was assessed by Dr Clayton Smith, a Medical Assessor, who issued a Medical Assessment Certificate (MAC) on 27 April 2023.
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, and
· 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 has conducted a review of the original medical assessment but limited to the ground(s) of appeal on which the appeal is made.
Rule 128 of the Personal Injury Commission Rules 2021 (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 r 128(1) of the PIC Rules.
The assessment of permanent impairment is conducted in accordance with the SIRA NSW Workers Compensation Guidelines for the Evaluation of Permanent Impairment, 4^th ed
1 March 2021 (the Guidelines) and the American Medical Association Guides to the Evaluation of Permanent Impairment, 5^th ed (AMA 5).

RELEVANT FACTUAL BACKGROUND

The appellant commenced employment with Constel Pty Ltd, the respondent, as a medical assistant on 12 November 2018. Due to conflict that occurred between her and her manager in the course of her employment she suffered a psychological injury on 20 October 2021.
On 4 October 2022 her solicitors wrote to the respondent’s insurer notifying it that the appellant claimed compensation under s 66 of the Workers Compensation Act 1987 (1987 Act) in the amount of $60,450 for 22% whole person impairment (WPI) from her injury. The appellant’s solicitors attached a copy of a report of consultant psychiatrist Dr Assad Saboor dated 21 September 2022 in support of the appellant’s claim. Dr Saboor had examined the appellant on 21 September 2022. He diagnosed the appellant had a major depressive illness with anxiety features. He assessed the appellant had 24% WPI but considered she had a pre-existing condition for which a one-tenth deduction ought to be made such that he assessed her WPI from her injury to be 22%. With respect to the pre-existing condition Dr Saboor noted that the appellant had a horrible sexual experience at the age of 16 and developed major depressive illness for which she received treatment. He noted that the appellant had the appellant had four previous psychiatric admissions and had been seeing a psychiatrist on a regular basis. He noted that the appellant had been diagnosed with ADD a few years prior to his consultation with the appellant for which the appellant had been prescribed Dexamphetamine. He noted she had stopped taking that medication.
Following receipt of the appellant’s claim the respondent’s solicitors organised for the appellant to be examined by psychiatrist Dr Alan Doris on 20 December 2022. Dr Doris considered that at the time he examined the appellant, the appellant had not achieved maximum medical improvement because there was further appropriate treatment that was likely to improve her condition. Dr Doris diagnosed the appellant had a major depressive disorder which he described as recurrent. He diagnosed the appellant had borderline personality traits.
Dr Doris further noted that the appellant had problems with her mood since adolescence and had a previous diagnosis of borderline personality disorder and major depressive disorder. He also noted that she had previous substance use disorders that were now in full remission. Dr Doris assessed that, at the time of assessment, the appellant’s WPI was 9%. He considered that the pre-existing mental health problems the appellant had contributed to the degree of her impairment. He considered that it would be difficult to quantify the contribution her problems made “in the different domains of PIRS”. When assessing the appellant’s impairment from her injury he made a 10% deduction on account of the appellant’s pre-existing mental health problems and hence, he assessed the appellant’s permanent impairment, at the date he assessed her, to be 8% from her injury.
On 4 January 2023 the respondent’s solicitors wrote to the appellant notifying her under s 78 of the 1998 Act that it disputed she was entitled to compensation for permanent impairment. It advised her that its reason for that was that her permanent impairment from her injury did not exceed 15% which under s 65A(3) of 1987 Act her permanent impairment needed to exceed for her to be entitled to compensation for permanent impairment. It advised her that it relied upon the opinion of Dr Doris and that it preferred Dr Doris’ opinion over Dr Saboor’s opinion.
The appellant then filed an Application to Resolve a Dispute dated 13 January 2023 in the Personal Injury Commission seeking determination of her claim for compensation.
The Medical Assessor examined the appellant on 11 April 2023. He assessed that the degree of her permanent impairment was 24% WPI. Neither party has raised any issue with that. The appellant’s Appeal relates to the deduction the Medical Assessor made under s 323(1) of the 1998 Act for a proportion of the appellant’s impairment that he considered was due to a pre-existing condition. The Medical Assessor assessed that proportion was 50% and he deducted that from the 24%WPI he assessed the appellant had, such that he assessed the degree of the appellant’s permanent impairment from her injury was 12% WPI.
The Medical Assessor set out in the MAC the following history relevant to the appellant’s pre-existing condition:
“BGW said her first contact with mental health services was at 16 when she was at school in Melbourne. She said she developed depression and anxiety several months after sexual trauma. She said she was suicidal. She said she had overdosed on antibiotics and was going to stab herself. She said her suicide attempts were always when someone was present. She said that although her home life was good, things were difficult at school because she was bullied. She said she was angry and frustrated because no one would listen to her about the sexual trauma. She said everyone had made judgements about the sexual trauma, and her family did not know. She said the issue divided her friends at school.
She asked her mother to see a psychiatrist, and her general practitioner prescribed
fluoxetine, and she was referred to a psychologist. She saw a psychologist for months. She said she subsequently found new friends and had the support of her sister. She said the situation at school deteriorated, and she only went to school twice a week. She said her father is in information technology and has worked worldwide. She said he was based in Sydney, but would work in America, then moved to Melbourne before moving and working in Asia.
She said she was in a relationship after school and was going to get married, but the relationship ended badly. She met her son’s father, but he had an affair with BGW’s best friend. She moved to the Whitsundays for her parent’s support. She started drinking excessively and developed alcohol dependence.
She said she was admitted to Manly Hospital when she was 20 after she took Ecstasy and developed depression. She said she was admitted around 2005 to Mackay Hospital with alcohol dependence, self-harm, and depression when she ‘hit rock bottom’. She was admitted to St John of God Private Hospital in Burwood under a psychiatrist, Dr Daniel Murray, in 2014 with depression. She said she saw Dr Murray several times, but he was an hour and a half drive away, and she saw him infrequently, approximately once every six to 12 months. She tried multiple antidepressants. She could not recall the antidepressants other than quetiapine and Valdoxan. She has been on fluoxetine for many years, and the dose was increased to 60mg since her last admission to St John of God Private Hospital.
She saw a psychologist regularly, saying she would dip in and out. More recently, she saw Dr Sandra Coates for four years in person in Belrose, a 10-15 minute walk weekly. She tried to do outpatient groups but could not manage due to the postural orthostatic tachycardia syndrome. She said she only attended for two to three weeks.
She said she was alcohol dependent in 1997 and had been sober since 18 December 2005. I note references to benzodiazepine dependence throughout the clinical records. She claims only to use diazepam every two to three days currently.
I note the impact of her son’s difficulties with the law just before the work-related injury and difficulties with the insurer funding a gastric sleep operation. I note her history of extensive absenteeism from work and her documented history of borderline personality disorder, childhood trauma, substance use disorder and recurrent major depressive disorder, such that she was on the Disability Support Pension before she was employed with the respondent.”
The Medical Assessor also set out in Part 10c. of the MAC the following observations he made from the records of various clinicians who had treated the appellant for her mental health prior to the date of her injury:
“Medical records from Eastbrooke Belrose Family Practice, various dates, noted a history of major depression, borderline personality disorder, and a diagnosis of ADHD by Dr Dominic Paul was noted in 2019.
Consultation notes from 28 August 2014, noted depression with prior trials of
antidepressants, ‘lots of them, but nothing works’, noting self-harm ‘has cut herself while driving her car’, benzodiazepine use (Xanax), previous trials of Pristiq, Effexor and Prozac, a diagnosis of borderline personality, admissions to Manly Hospital and Mackay Hospital, abstinence from alcohol.
On 1 September 2014, she was recommended admission to Northside Cremorne by her psychologist, Jennifer Mitchell, for dialectical behaviour therapy (a treatment typically for borderline personality disorder). She was on fluoxetine in 2015, and quetiapine. She was noted to have anxiety and panic attacks in May 2016. Referral to a psychiatrist and psychologist was recommended. She presented for treatment of major depression in August 2016, noting that her mood was stable, requiring a new script for fluoxetine. She continued to use benzodiazepines, noting 3 tablets of temazepam per night in June 2017. Suicidal thoughts were noted in August 2017 in the context of insomnia. She was referred back to Dr Daniel Murray, Psychiatrist. She remained on benzodiazepines (oxazepam). She was referred to a psychologist in September 2017, was only seeing her psychiatrist once a year. The dose of fluoxetine was increased to 60mg. She was prescribed adjunctive agomelatine. She continued psychotherapy in January 2018 under the ATAPS scheme.
Akathisia was noted on 8 August 2018 after taking quetiapine and agomelatine, a common side-effect of antipsychotic medications and some antidepressants. She was noted to have difficulty concentrating at work on 5 July 2019 and querying ADHD. She remained on oxazepam. She was noted to have anxiety in the context of her son’s arrest and charge at Schoolies in November 2019. She was prescribed dexamphetamine in 2019 for ADHD. She was noted to be very stressed due to her son’s charges in February of 2020. The stress was ongoing in April 2020 in relation to her son. Difficulties with benzodiazepines were flagged in April 2020. She was referred to Dr Dominic Paul, Psychiatrist, in June 2020 for insomnia, anxiety, and benzodiazepine dependence. She was prescribed mirtazapine 15mg in July 2020. The dose of mirtazapine was halved in September 2020. She was on a reducing regime of alprazolam in November 2020.
Medical records from Whitsunday Doctors Service, as at 4 September 2014, also documented depression in 1992 and 2014, alcohol dependence in 1997, no alcohol since 28 years of age, confirming scripts for Pristiq, benzodiazepine, referral for a psychologist, a suggested diagnosis of borderline personality disorder in November 2005, and benzodiazepine dependence.
Initial assessment letter from Dr Jennifer Mitchell, Psychologist, dated 30 August 2014, noted features of borderline personality disorder and depression, recommending inpatient treatment and intensive team outpatient care. She was noted to disengage from treatment after relocating to the Whitsundays to live with her parent around October 2014. It is noted in a letter by Kerry Callahan, Clinical Psychologist, dated 9 February 2015, to have moderate to severe depression and a referral for dialectical behaviour therapy, noting that BGW was a complex client due to her suicide risk. She noted risk factors, including a diagnosis of borderline personality disorder, previous deliberate self-harm and significant alcohol abuse. Dialectical behaviour therapy was proposed. BGW disengaged with treatment around 12 May 2015 due to poor attendance.
Initial assessment report by Dr Daniel Murray, dated 30 May 2016, noted anxiety, depression and a borderline vulnerability, noting that Dr Murray had worked with her in 2014. She was noted to be off benzodiazepines at that point. He noted the impact of POTS syndrome. In August 2017, Dr Murray recommended augmentation of fluoxetine with agomelatine, after increasing the dose of fluoxetine to 40mg.
A mental health triage form from Sydney North Primary Health Network, dated 11 September 2017, noted depression since the age of 16, on medication most of that time, ceased early 20s, recommenced at aged 24, past history of heavy drinking 24/25 to age 28, then ceased, no other substance abuse, suicide attempts at aged 24/25, drug, alcohol and some self-harm, nil attempts since. She was noted to have an adjustment disorder with mixed anxiety and depressive symptoms and a grief reaction on 4 May 2022 by Dr Dominic Paul, due to the loss of her ex-fiancé.
…
A letter from Dr Monica Goldsmith, dated 1 September 2014, General Practitioner, noted a diagnosis of borderline personality disorder with chronic depression, confirming two previous admissions at Manly Hospital aged 22 and Mackay Base Hospital around 2006.
…
Records from St John of God confirmed admissions to St John of God Hospital in 2014. A support letter for the Disability Support Pension by Luke Orrick, the social worker at St John of God Hospital dated 19 September 2014, noted a complicated history of mental illness with major depressive disorder and borderline personality disorder since she was a teenager. He noted that she had seen over 20 psychologists and psychiatrists and had had several hospital admissions. He noted that although she had had brief periods of wellness, she experienced long and debilitating periods of instability and unwellness. He strongly supported her application for the Disability Support Pension.
Records from Northern Beaches Hospital noted presentations with suicidal thoughts in the context of various stressors. The principal cause of the admission in February 2021 was uncertainty about whether her insurer would accept her claim for gastric sleeve surgery. She was discharged in February of 2021 after the procedure was approved.”
The Medical Assessor provided the following summary of injuries and diagnoses relating to the appellant:
“BGW is a 46-year-old woman previously employed as a medical administrator for a radiology practice. She developed an aggravation of a recurrent major depressive disorder on a background of borderline personality disorder after she felt betrayed, isolated and unsafe with her employer. Her mental health was unstable in the lead-up to the injury. She was admitted to a psychiatric hospital in February 2021 due to uncertainty about an insurer funding a gastric sleeve. She has an extensive mental health history, personality vulnerabilities and sexual trauma and social problems at school in adolescence. She was on the disability support pension for depression and POTS when the respondent employed her.
BGW currently meets the DSM-V criteria for a major depressive disorder characterised by persistently depressed mood, loss of interest in previously enjoyed activities, fatigue, impaired concentration, depressive thoughts, including passive suicidal thoughts, and sleep disturbance/insomnia. The current episode represents a recurrence of a longstanding pre-existing major depressive disorder.
I am satisfied from the documentation that BGW meets DSM-V criteria for borderline personality disorder, characterised by a pervasive pattern of instability of interpersonal relationships, self-image and affects and marked impulsivity, beginning by early adulthood and present in a variety of contexts, as indicated by a pattern of unstable and intense interpersonal relationships, identity disturbance, markedly and persistently unstable self image or sense of self, impulsivity in at least two areas that are potentially self-damaging, such as substance use, recurrent suicidal behaviour, gestures, or threats or self-harming behaviour, affective instability due to a marked reactivity of mood, for example intense episodic dysphoria, irritability or anxiety usually lasting a few hours and only rarely more than a few days, inappropriate, intense anger or difficulty controlling anger and transient, stress-related paranoid ideation or severe dissociative symptoms.
The diagnosis of borderline personality disorder is established from the longitudinal history (particularly her responses to various stressors), a history of sexual trauma, the medical evidence provided by BGW’s treating clinicians, the more recent evidence from her admissions to the Northern Beaches Hospital Psychiatric unit, and collateral history provided by BGW’s sister documented during her admission to the Northern Beaches Hospital in 2021.
She had an alcohol use disorder in sustained remission for over 20 years. She was dependent on benzodiazepines until her admission to the Hills Clinic.
The diagnosis of POTS is outside my area of expertise. Still, it is likely to contribute to BGW’s psychological status by compounding the neurovegetative symptoms (those symptoms directly related to the body such as fatigue) of major depressive disorder. Both borderline personality disorder and recurrent major depressive disorder are pre-existing conditions that substantially impact the work-related injury. They both substantially increase the risk of further depressive episodes, particularly in the context of interpersonal stressors due to maladaptive coping and distorted models of relating.
Apportionment for the effects of pre-existing conditions is discussed below.
Her account was consistent with the medical evidence provided by her treating clinicians. The mechanism of injury was consistent with the symptoms described. She has had evidence-based treatment for both a major depressive disorder and borderline personality disorder with difficulties accessing or adhering to longer-term group psychotherapy, such as dialectical behaviour therapy, partly due to the cost associated with private outpatient programs and the effects of POTS. Given the duration of the effects of the injury and the underlying vulnerabilities and pre-existing conditions and the assertive evidence-based pharmacotherapy and long-term individual psychotherapy, her condition has stabilised at a moderately severe level. She has reached maximum medical improvement. Her impairment is unlikely to vary substantially over the next 12 months with or without treatment.”

The Medical Assessor said at Part 11a. of the MAC that the pre-existing conditions the appellant had at the time of her work injury were recurrent major depressive disorder and borderline personality disorder. The Medical Assessor said that those conditions impacted the appellant’s function at work preceding her injury and “substantially impact the work related injury”. The Medical Assessor said that the pre-existing condition the appellant had “both perpetuate the current depressive episodes and are independent risk factors for recurrent depressive episodes”.
At Part 10c. of the MAC the Medical Assessor indicated that he considered a proportion of the appellant’s permanent impairment from her injury was due to the appellant’s pre-existing condition and consequently a deduction needed to be made under s 323(1). He also said “deduction is difficult or costly to determine”. He said that “the available evidence is that the deductible proportion is large and a deduction of one-tenth is at odds with the available evidence”. He said that in his opinion the deductible proportion should be 5/10. He explained this was because the appellant’s “current impairment is a product of both pre-existing psychological disorders and the effects of the subject injury”. He explained that the appellant’s pre-injury psychological status was fragile and that impacted her work function and that the “index event”, by which the Appeal Panel understands the Medical Assessor meant work injury, “worsened a pre-existing clinical level psychological disorder”.
The Medical Assessor explanation for finding that the proportion of the appellant’s permanent impairment that was due to her pre-existing conditions was 50% also included the following:
“(i) The current impairment is a product of both pre-existing psychological disorders and the effects of the subject injury. BGW’s pre-event psychological status was fragile and impacted her work function. The index event worsened a pre-existing clinical level psychological disorder.
(ii) The link between the criticism from her manager and colleagues, the subsequent loss of her employment, and her depressive symptoms are clear, confirming an ongoing work-related component to her mood disorder and the aggravation of borderline personality disorder. I cannot conclude that the larger portion of her psychological impairment arises from a work-related psychological injury. The preexisting condition and the work-related injury had substantial impacts; one is not greater than the other.”

PRELIMINARY REVIEW

The Appeal Panel conducted a preliminary review of the original medical assessment in the absence of the parties and in accordance with the Procedural Direction PIC7.
As a result of that preliminary review, the Appeal Panel determined that it was not necessary for the respondent to undergo a further medical examination. This is for two reasons. Firstly, the Appeal Panel, for reasons explained below, found that neither of the grounds for appeal on which the appellant relied was established. Consequently, the Appeal Panel confirmed the MAC and did not need to re-assess the medical dispute that had been referred for assessment. Secondly, absent the Appeal Panel finding error in the MAC, the Appeal Panel does not in any event have power to examine the appellant.[1]
[1] NSW Police Force v Registrar of the Workers Compensation Commission of NSW [2013] NSWSC 1792 at [33]; Ziraki v The Australian Islamic Liverpool Area [2019] NSWSC 1158 at [74]; Coenradi v the GEO Group Australia Pty Ltd [2002] NSWSC 864 at [134]; and Finnegan v Komatsu Forklift Australia Pty Ltd [2023] NSWSC 38 at [125]-[130].

EVIDENCE

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

SUBMISSIONS

Both parties made written submissions. They are not repeated in full, but have been considered by the Appeal Panel.
In summary, the appellant submitted that she had “no non-work stressors” at the relevant time. The appellant submitted that the effect of her injury “was profound” and resulted in her hospitalisation. The appellant submitted that there was no evidentiary basis to justify a large deduction being made under s 323(1). The appellant submitted that there was nothing in the clinical material in evidence that demonstrated “a high level of psychiatric difficulty outside of the work stressors”. The appellant submitted that the evidence indicated the contrary because she had been able to work and only ceased work because of her injury.
The appellant submitted that the appellant’s psychiatric illness was long standing and of obscure origin and that it is difficult to determine precisely the proportion of her permanent impairment due to her past psychiatric illness and consequently “it is appropriate to deduct 10% per s 323(2)”.
The appellant observed that both Dr Saboor and Dr Doris when assessing her permanent impairment from her injury made a deduction of only 10%.
The appellant submitted that the two reasons the Medical Assessor provided for making a deduction of 50% under s 323(1) were “not persuasive”. The appellant submitted that the Medical Assessor’s reason that her current impairment is a product of her pre-existing psychological illness and the effects of the injury “is merely a statement of the circumstances that call for the application under s 323”. The appellant submitted that the Medical Assessor’s reason that her injury worsened a pre-existing clinical level psychological disorder is also “merely a statement of the need to apply s 323, but not to any particular extent”.
The appellant submitted that the Medical Assessor’s explanation that he could not “conclude that the larger portion of the psychological impairment arises from a work related psychological injury” indicates why it was difficult and costly to determine the deductible proportion such that s 323(2) should have been engaged and the Medical Assessor ought to have assumed that the deduction was 10% only. The appellant submitted that the Medical Assessor’s explanation that her pre-existing injury and work related injury had substantial impacts and one is not greater than the other is arbitrary and wrong because the pre-existing condition did not stop her from doing the work in which she was injured. The appellant submitted that her “previous pathological state was less substantial than her work related state”. The appellant submitted it was impossible to measure the extent of the respective contributions to the totality in a scientific or mathematical way and therefore a deduction of 10% ought to have applied.
In reply, the respondent submitted that the Medical Assessor obtained a thorough history of the appellant’s pre-existing condition and several hospital admissions. The respondent submitted that the Medical Assessor accepted the appellant suffered an aggravation of a Major Depressive Disorder but did not think her entire impairment was attributable to the work related incident. The respondent submitted that the Medical Assessor clearly arrived at a conclusion that to assume a deduction of one-tenth was to be made under s 323(2) was at odds with the Medical Assessor’s evidence. The respondent submitted that the Medical Assessor was of the view that the appellant’s pre-existing diagnoses impacted her functioning at work leading up to her injury.

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.
In Campbelltown City Council v Vegan [2006] NSWCA 284 the Court of Appeal held that the Appeal Panel is obliged to give reasons.
The appellant does not dispute that the Medical Assessor was correct to find that a proportion of her permanent impairment resulting from her injury was due to a pre-existing condition. Further, the appellant does not raise any issue about the pre-existing conditions that the Medical Assessor diagnosed she had, to which a proportion of her permanent impairment was due, namely recurrent major depressive disorder and borderline personality disorder.
The appellant contends that it was too difficult to determine with any mathematical or scientific precision the proportion of her permanent impairment that was due to her pre-existing condition and, in accordance with s 323(2), the Medical Assessor was required to assume the proportion of her permanent that was due to her pre-existing conditions was 10%. The appellant observed that both Dr Saboor and Dr Doris when assessing her permanent impairment from her injury made a deduction of only 10%.
A proportion of permanent impairment will be due to a pre-existing condition if that condition makes a difference to the outcome for the worker in terms of the degree of permanent impairment resulting from the work injury.[2] Hence, to the extent that the pre-existing condition makes a difference to the outcome there must be a deduction. A Medical Assessor’s assessment of the extent to which a worker’s permanent impairment resulting from a work injury is due to a pre-existing condition is a matter for medical assessment based on the evidence before the Medical Assessor.[3] Consequently, the fact that other clinicians may have differing opinions regarding the extent to which a pre-existing condition makes a difference to the outcome of a worker’s permanent impairment from an injury is not sufficient to establish error if the Medical Assessor’s assessment of the matter was open to the Medical Assessor to make.
[2] Ryder v Sundance Bakehouse [2015] NSWSC 526 at [45].
[3] Drosd v Workers Compensation Nominal Insurer [2016] NSWSC 1053 at [74]-[86].
Section 323(2) of the 1998 Act stipulates that a Medical Assessor must assume the proportion to which a worker’s permanent impairment from a work injury is due to a pre-existing condition is 10% if it will be difficult or costly to determine what the deduction under s 323(1) should be, so long as making that assumption is not at odds with the available evidence. Hence, in a circumstance where the evidence indicates that making such an assumption is wrong then a Medical Assessor can not make the assumption and must assess the matter as best he or she can with the available evidence.
In this matter the Medical Assessor set out within the MAC the appellant’s extensive history of psychiatric illness that preceded her work place injury. Her earliest history commenced with a diagnosis of depression when she was 16 years of age. Most recently before she suffered her work injury she had been admitted to the Northern Beaches Hospital with suicidal thoughts in the context of various stressors, principally uncertainty about whether an insurer would accept a claim she made for gastric sleeve surgery.
The Appeal Panel also observes from the clinical records of the Eastbrooke Belrose Family Practice that a note was made of a consultation on 29 November 2019 when the appellant presented with a severe anxiety attack due to her son being arrested at a “schoolies” event on the Gold Coast. On 29 January 2020 the appellant again consulted the practice and a note regarding that consultation was made that the appellant was feeling depressed and had started cutting herself.
The Medical Assessor noted within the MAC his observations from the clinical material within the evidence before him relating to the appellant’s prior treatment for her psychiatric illnesses. Those observations, and indeed the evidence upon which they are based, indicates that the appellant had extensive treatment for psychiatric illness over several years until recently before her work injury, including hospitalisations.
The Medical Assessor’s reasons for concluding that the proportion of the appellant’s permanent impairment from her injury was due to her pre-existing conditions were that:
(a)    the appellant’s impairment is both the product of her prior psychiatric illnesses and her work injury;
(b)    the appellant’s work injury “worsened a pre-existing clinical level psychological disorder”;
(c)    both the appellant’s pre-existing condition and her work injury had substantial impacts and that one is not greater than the other; and
(d)    he could not conclude that a larger proportion of the appellant’s impairment results from her injury than her pre-existing conditions.
Those reasons of the Medical Assessor, in the Appeal Panel’s view, amount in substance to his finding that to make an assumption that the proportion of her permanent impairment due to her pre-existing conditions is 10% would be at odds with the evidence before him. In other words, s 323(2) could not be engaged to determine the deduction to be made under s 323(1).
The Medical Assessor set out in the MAC the evidence that was at odds with making an assumption that the deduction to be made under s 323(1) is 10%. That evidence was the history he obtained regarding the appellant’s prior psychiatric illness and the clinical material that recorded the appellant’s past presentations to her treating clinicians and the treatment she had for her pre-existing conditions. When the MAC is considered as a whole, the Appeal Panel considers that the Medical Assessor provided adequate reasons for concluding why that evidence was at odds with making an assumption that the deductible proportion should be 10%. When the MAC is considered as a whole it is apparent why the Medical Assessor formed that view, and the Appeal Panel, which is an expert panel, agrees with it.
It is the case, as the appellant submitted, that the reasons the Medical Assessor provided for making a deduction of 50% required consideration of whether s 323(2) should be engaged. But, contrary to what the appellant submitted, the reasons the Medical Assessor provided were not “merely” for that purpose. His reasons also explained why it was that making an assumption that the proportion to be deducted under s 323(1) should be 10% was at odds with the evidence, and why it was that the deduction to be made under s 323(1) should be 50%. It was not an arbitrary figure that the Medical Assessor selected. It was based on the evidence before him and explained by him.
It does not matter that Dr Saboor and Dr Doris had a different view than the Medical Assessor. The Medical Assessor was required to make his assessment based upon his clinical judgment. He had regard to the opinions of Dr Saboor and Dr Doris, but the exercise by him of his clinical judgment led him to different opinion. The Appeal Panel observes too that Dr Saboor did not set out in his report of 21 September 2022 a complete history of the appellant’s prior psychiatric illness nor did he provide, in the Appeal Panel’s view, a cogent explanation for making a deduction of 10% under s 323(1). As the Appeal Panel has indicated, the Medical Assessor set out a fulsome history of the appellant’s psychiatric illness and treatment for it and provided an adequate, and indeed cogent, explanation for the deduction he made under s 323(1).
Dr Doris in his report provided a more complete history of the appellant’s psychiatric illness than Dr Saboor, but in the Appeal Panel’s view, Dr Doris also did not explain in any cogent way why, having had regard to that history, he considered a deduction of only 10% ought to be made.
In any event, as has been said, the Medical Assessor, in the Appeal Panel’s view, has provided a cogent explanation for the deduction he made and the deduction he made was based on the material before him.
The Appeal Panel does not accept the appellant’s submission that nothing can be found within the clinical material that demonstrated a high level of psychiatric difficulty outside of work stressors. As earlier mentioned, the appellant was most recently before she suffered her work injury admitted to the Northern Beaches Hospital with suicidal thoughts and depression in February 2021. That admission related to an issue that arose between her and a medical insurer. Around a year prior to that, the appellant was presenting to her general practitioner with symptoms of anxiety and depression and was self harming due to stress she was experiencing as a consequence of her son being arrested. The point is that the appellant was suffering psychiatric illness before her work injury and this was impacting adversely of her function.
In summary, the Appeal Panel considers that the Medical Assessor was correct to conclude, for the reasons he provided, that assuming the proportion of the appellant’s permanent impairment resulting from injury that was due to her pre-existing conditions was 10% was at odds with the evidence. The Appeal Panel considers that the Medical Assessor did not err in the exercise of his clinical judgment in assessing that the proportion of the appellant’s permanent impairment resulting from her injury that was due to her pre-existing conditions was 50%. That opinion was open to the Medical Assessor and the Medical Assessor explained why he formed that opinion. The Medical Assessor did not apply incorrect criteria to make his assessment of the appellant’s permanent impairment, given that his assessment was based on the criteria as set out in Chapter 11 of the Guidelines and based on a correct application under s 323 of the 1998 Act.
For these reasons, the Appeal Panel has determined that the MAC issued on 27 April 2023 should be confirmed.

[2023] NSWPICMP 355

26 July 2023