1. On 24 March 2025 the State of New South Wales (NSW Health Pathology) (referred to in the file as SEALS) lodged an Application to Appeal Against the Decision of a Medical Assessor. The medical dispute was assessed by Medical Assessor Christopher Rikard-Bell, who issued a Medical Assessment Certificate (MAC) on 24 February 2025.
2. SEALS relies on the following grounds of appeal under s 327(3) of the Workplace Injury Management and Workers Compensation Act 1998 (the 1998 Act):
   • the assessment was made on the basis of incorrect criteria, and
   • the MAC contains a demonstrable error.
3. The President's delegate was satisfied that, on the face of the application, at least one ground of appeal was capable of being made out, being that the Medical Assessor erred in making a deduction of one-tenth under s 323 of the 1998 Act. We conducted a review of the original medical assessment, limited to the grounds of appeal on which the appeal is made.
4. Rule 128 of 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 r 128(1) of the PIC Rules.
5. The assessment of permanent impairment is conducted in accordance with the SIRA NSW Workers Compensation Guidelines for the Evaluation of Permanent Impairment, 4th ed 1 March 2021 (the Guidelines) and the American Medical Association Guides to the Evaluation of Permanent Impairment, 5th ed (AMA 5).

1. Ms Wu's claim for compensation has a long and complex history. Ms Wu was employed by NSW Health Pathology Services in South Eastern Area Laboratory Services (SEALS) from 7 June 2010 as a blood collector. She worked concurrently for two other employers. She claimed compensation for a psychological injury as a result of events in her employment with SEALS between 18 January 2011 and 4 March 2014.
2. Ms Wu commenced proceedings in 2022 which were dismissed by a Member of the Personal Injury Commission (Commission) for want of due despatch. She commenced the current proceedings in November 2022. A Member of the Commission declined to permit SEALS to file an Application to Admit Late Documents and SEALS appealed that decision. On 15 June 2023 Phillips P allowed the appeal and referred the matter back to the Member for determination.
3. On 3 November 2023, Member Garner determined that Ms Wu suffered a primary psychological injury with a deemed date of 4 March 2014 and made orders remitting the matter for referral to a Medical Assessor.[1]
4. SEALS then appealed that decision on the narrow basis that the Member did not give adequate reasons for her findings, particularly in determining that Ms Wu was a reliable witness. Acting Deputy President Sweeney confirmed the Certificate of Determination on 28 November 2024[2] and the matter was referred to the Medical Assessor.
5. The Medical Assessor assessed 17% whole person impairment (WPI) using the Psychiatric Impairment Rating Scale (PIRS), placing Ms Wu in class 2 for self-care and personal hygiene, travel and concentration, persistence and pace. He assessed her in class 3 for social and recreational activities and social functioning and class 4 for employability. He made a deduction of one-tenth of the assessment under s 323 of the 1998 Act so that the final assessment was 15% WPI.

1. We conducted a preliminary review of the original medical assessment in the absence of the parties and in accordance with the Procedural Direction PIC7.
2. As a result of that preliminary review, we determined that it was not necessary for Ms Wu to undergo a further medical examination because the MAC does not disclose error and there is sufficient information in the file to determine the appeal.

1. We have all the documents that were sent to the Medical Assessor for the original medical assessment and have taken them into account in making this determination.
2. The parts of the MAC that are relevant to the appeal are set out in our reasons below.

1. Both parties made written submissions. They are not repeated in full, but we have considered them. We return to some of the submissions in more detail in our reasons below.
2. In summary, SEALS submitted that the Medical Assessor erred in his assessments under the PIRS for social and recreational activities, social functioning and employability. It said that the Medical Assessor was in error to make a deduction of only one-tenth under s 323 of the 1998 Act.
3. With respect to social and recreational activities, SEALS said that the Medical Assessor did not have adequate regard to Ms Wu's pre-injury level of functioning and the effects of a

pre-existing paranoid disorder and that she did not go out socially before the injury. With respect to social functioning, SEALS said that the Medical Assessor did not establish the reason for Ms Wu's separation from her husband in 2018 and whether it was attributable to her work-related condition. SEALS also argued that the Medical Assessor did not have regard to Ms Wu's pre-existing condition when assessing employability. 4. SEALS argued that a deduction of one-tenth under s 323 was at odds with the history in the file and that s 323(2) applied when the extent of the deduction is difficult or costly to determine and such a deduction was not at odds with the available evidence. SEALS said that Medical Assessor did not explain whether Ms Wu's psychological injury which was to be assessed was characterised as an "aggravation of this pre-existing delusional disorder or some other psychiatric diagnosis." 5. SEALS said that it was open to the Medical Assessor to find that the extent of the deduction was difficult to determine but that one-tenth was at odds with the available evidence. SEALS did not nominate the extent of the deduction that would be appropriate. 6. In reply, Ms Wu submitted that the delusional disorder that she suffers developed during the period between 2011 and 2014 when she was employed by SEALS. She submitted that the assessments made by the Medical Assessor in respect of the impugned PIRS tables were appropriate. 7. Ms Wu noted that Member Garner found there was no formal psychiatric diagnosis before she commenced working for SEALS in 2010 and said that the Medical Assessor's deduction of one-tenth was valid.

1. The procedures on appeal are contained in s 328 of the 1998 Act. The appeal is 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.
2. In Campbelltown City Council v Vegan[3] the Court of Appeal held that an 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.
3. In Queanbeyan Racing Club Ltd v Burton[4] the Court of Appeal held that an Appeal Panel is not limited to the ground held to have been made out by the delegate but may consider all grounds of appeal raised in the application. However, the panel is not permitted to look for errors which are not part of the grounds of appeal on which the appeal is made. We have only considered those grounds specifically raised by the appeal.
4. We comment at the outset that the file is large and the MAC itself is long. We have reviewed the file in detail but we have limited our extracts from the material to those which are necessary to explain the reasons for our decision.
5. Ms Wu relied on Dr Stevan's report dated 24 June 2016 to claim compensation for 48% WPI. Ms Wu was later assessed by Dr Kuljic who assessed 28% WPI in his report dated 27 November 2021.
6. SEALS did not rely on any assessment of WPI. Dr Samuell, psychiatrist, examined Ms Wu and reported on 9 December 2016. He considered that Ms Wu required intensive treatment and did not assess WPI.
7. In his second report dated 6 June 2022, Dr Samuell said that Ms Wu may require

electro-convulsive therapy for severe melancholic depression and that her prognosis was bleak. He said that if her narrative was taken at face value, his assessment of WPI was not markedly different from that made by Dr Kuljic. He did not set out his assessment of WPI nor did he express an opinion as to a deduction under s 323.

1. The Medical Assessor set out the history he obtained, saying:

"I asked Ms Wu about the issues at work and she had some difficulty explaining what occurred and what the workplace problems entailed. Ms Wu stated she believed she was the victim of harassment, denigration and humiliation. Although she claimed there were no previous workplace issues, clearly there was a pre-existing history."

1. The Medical Assessor noted that Ms Wu separated from her husband in 2018. He set out his mental state examination in some detail. He said that Ms Wu was quite sullen and withdrawn for much of the interview and there was little reactivity, until they spoke about her beliefs as to how she had been mistreated when she became more animated. Ms Wu told the Medical Assessor that she has heard voices saying critical things about her, though the Medical Assessor said it was difficult to obtain a clear picture or character of the voices. He said:

"Ms Wu's affect was depressed but there was some reactivity and she did become a little animated when talking about her experience. Her thoughts were logical. She was able to explain herself and speak logically, although her ideas appeared to be paranoid in that she believed there was a conspiracy and that the staff at work were against her. Ms Wu still believes there was a conspiracy to undermine and humiliate her. She does not like to open the door as she does not want to see the faces of people who come to her unit and she closes the blinds. She believes that there are still people from the workplace who are spying on her although she could not explain why they would be spying on and she believes this is an ongoing problem."

1. The Medical Assessor said that Ms Wu denied a previous history of anxiety, depression or mental health issues, though he noted some references to anxiety and depression dating back to 2007 and a reference to a compensation claim as a result of humiliation in the workplace in 2009.
2. After setting out Ms Wu's personal, relationship and work history, the Medical Assessor turned to her current functioning. He said:

"Ms Wu is able to make herself a meal in the evening and she will eat cereal in the morning. She is able to cook and clean for herself to a certain degree. Her daughter assists with shopping and cooking. Therefore, there is mild impairment of self-care and personal hygiene.

Ms Wu separated from her husband in 2018, although her ex-husband will assist if she calls on him and her children visit once per week. Therefore, there is moderate impairment of social functioning.

Ms Wu cannot concentrate well and she does not like to read a great deal, however, she was able to concentrate for the full 2 hours of the interview today. Therefore, there is mild impairment of concentration, persistence and pace.

In terms of social and recreational activities, Ms Wu enjoys seeing her grandchild but she does not go out with friends or interact with others and she stays at home. Therefore, there is moderate impairment of social and recreational activities.

In terms of employability, Ms Wu has not worked since 2015 and there is severe impairment of employability.

In terms of travel, Ms Wu initially stated she does not drive then indicated she does drive short distances. Therefore, there is no impairment of travel."

1. In the PIRS table, the Medical Assessor said there was mild impairment of travel.
2. Describing Ms Wu's current routine, the Medical Assessor wrote:

"Ms Wu will go to bed at random times and wakes up at "any time." She will go into the garden and will do some chores occasionally. She goes to the local shops to do a small amount of shopping but her daughter will accompany her on larger shopping trips. In the afternoon Ms Wu stays home. There are weekly general practitioner consultations however she is unable to afford psychological or psychiatric treatment. She last consulted a mental health practitioner over six years ago."

"Ms Wu was an inaccurate historian denying any previous mental health issues, however, from the general practitioner records, there was stress and hypertension reported in June 2009. On 10 February 2009 there was an incident reported when a patient urinated on her shoes and she claimed workers compensation. Therefore, there is a clear history of difficulties managing stress from 2005 to 2012. In 2012 there was conflict with a tenant leading to Police involvement and her admission to St George Hospital where it was noted there was an acute situational crisis. There was follow up with the acute care team in January 2013 and she was referred for psychological treatment with Ms Ling. At the time, Ms Wu was feeling harassed by the tenant."

1. The Medical Assessor said that Ms Wu "experienced workplace stress before 2011 and certainly before 2013." He summarised her treatment and noted that the "workplace has continually denied any responsibility for Ms Wu's alleged difficulties." He said:

"From the range of diagnoses and difficulties with trying to determine what has occurred over the past 15 years, I formed the view Ms Wu most likely does have a mental illness. I believe the most likely diagnosis is a paranoid disorder, however, there appears to be a lot of confusion among the experts with regard to a formal diagnosis. Dr Samuell was unclear while Dr Stevans, Dr Protulipac, Dr Kuljic, Dr Roberts, Mei Tze Ling and Dr Zhang outlined differing perceptions. In addition, Dr Samuell, Dr Roberts and Dr Kneebone found Ms Wu was an unreliable historian and there were difficulties assessing and weighing the information provided. From my perspective, the differential diagnoses are persistent depressive disorder, chronic adjustment disorder, major depressive disorder, major depressive disorder with psychosis, paranoid personality disorder or delusional disorder. On balance, the most likely explanation is that Ms Wu has developed a delusional disorder that most likely commenced before her experiences at SEALS."

1. The diagnosis - which is not challenged on the appeal - is "delusional disorder, persecutory type". The Medical Assessor considered that Ms Wu suffered a pre-existing paranoid disorder.
2. The Medical Assessor was required to assess Ms Wu as she presented on the day of the examination[5] and arrive at an assessment of permanent impairment using the PIRS. He was then required to apply s 323 to determine any extent to which the impairment assessed is due to a previous injury.

1. The Medical Assessor assessed Ms Wu in class 3 because:

"In terms of social and recreational activities, Ms Wu enjoys seeing her grandchild but she does not go out with friends or interact with others and she stays at home. Therefore, there is moderate impairment of social and recreational activities."

1. The history taken by the Medical Assessor of Ms Wu's activities supports that assessment.
2. SEALS argued that the Medical Assessor failed to take account of Ms Wu's pre-injury functioning when assessing her in class 3 and that the reason for not leaving the house was a result of her pre-existing condition. SEALS said that Ms Wu should be assessed in class 2 because of the ongoing effects of her pre-existing condition. It stressed that Ms Wu told Dr Roberts, psychologist, in 2022 that she has no friends and that the last time she went out socially was her son's wedding in 2000.
3. What Dr Roberts wrote was slightly different to what is recorded in SEALS' submissions. She said:

"Ms Wu told me that she has no friends, adding 'I'm not interested. I asked the last time she went out socially. She replied 'I have no social activity, plus there's a pandemic.' I asked the last time she went out socially, and she replied 'many years.' That's when my son got married, in 2000, and that's the last time I went out socially."

1. It is unlikely that Ms Wu's son married in 2000. Dr Roberts recorded in 2022 that Ms Wu said "my son is 30+, around 35." The Medical Assessor recorded that her son is 37. In 2000, he would have been about 12. It is more likely that his wedding took place while Ms Wu was working at Pathology or after she left.
2. Based on the history the Medical Assessor took, assessment in class 3 was correct.
3. The Medical Assessor was not required to apply s 323 until he had assessed WPI. In seeking to argue that Ms Wu's impairment of social functioning was a result of a pre-existing condition, SEALS was asking that any such impairment be taken into account twice.

1. The Medical Assessor assessed Ms Wu in class 3 because:

"Ms Wu separated from her husband in 2018, although her ex-husband will assist if she calls on him and her children visit once per week. Therefore, there is moderate impairment of social functioning."

1. SEALS sought to argue that the Medical Assessor was required to establish the circumstances of Ms Wu's separation and whether it was a result of the pre-existing condition. Again, that is a submission that pre-existing impairment should be relied on to reduce the Medical Assessor's primary assessment and does not take account of the Medical Assessor's obligation to assess Ms Wu on the date of the examination. SEALS argued that the Medical Assessor should have assessed Ms Wu in class 2.
2. There is information in the file about the circumstances of Ms Wu's separation. SEALS quoted from Dr Roberts report dated 1 May 2018 to say that Ms Wu "gets on well with her daughter and goes to see her twice a week" and that, while separated from her husband, she had contact with him and they are still friends. The relevant part of Dr Roberts' report, read as a whole, provides considerable further detail. It reads:

"Ms Wu told me that she lives at home with her sister, has been there for a year and before that, lived with her husband. I asked what happened. She replied (tearfully) 'we got divorced. He disliked me'. I asked how long he had disliked her. She replied 'for around a year.' I asked the cause. She replied 'I'm not the person I used to be.' She told me that she still has contact with him and that they are still friends. I asked about the children. She told me that they have a 32 year old son, who works doing research in the Department of Education and lives independently, and a 17 year old daughter, who lives with her father and is doing the HSC this year. She told me that she gets on well with her daughter and goes to see her twice a week. She told me that her daughter stayed with her husband. When asked why, she replied 'I can't look after her and I don't want to interrupt her study. She is an excellent student.'"

1. Ms Wu was still married at the time Dr Samuell, psychiatrist, saw her at the request of SEALS in 2016 and when she saw Dr Stevans at the request of her former solicitors in the same year, though Dr Stevans recorded that her relationship was strained.
2. Dr Kuljic assessed Ms Wu on behalf of her solicitors in 2021 and recorded:

"I had friendly neighbours, a good relationship, and no problems with my colleagues at work. We socialized at work, and I enjoyed it. I do not mix with anybody now. My relationship with my kids suffered because I became very irritable and argumentative. My marriage suffered from my work-related problems. I became a grumpy person with a bad temper. Due to that, we separated six years ago, and we divorced a year later."

1. In Dr Roberts' second report dated 29 June 2022 she recorded:

"I asked how she manages money-wise. She replied 'I have two children. They support me. My daughter is 20 and my son is 30+, around 35. He is married. I haven't got any grandchildren. He works with the government in the Education Department. My daughter lives with me in a house and I own it. I got divorced several years ago. There were problems in the marriage after this happened. I have no contact with him (ex-husband). He has contact with the kids."

1. Ms Wu has consistently provided a history as to the breakdown of her marriage after the injury. There is no error in the Medical Assessor's assessment in class 3.

1. The Medical Assessor assessed Ms Wu in class 4 because:

"In terms of employability, Ms Wu has not worked since 2015 and there is severe impairment of employability."

1. SEALS argued that the Medical Assessor should have taken Ms Wu's pre-existing functioning into account and that Ms Wu was unable to explain why she stopped working at SEALS and her other jobs. It said that the Medical Assessor did not take into account the fact that she worked until 2015 nor the fact that she is now 67.
2. The relevance of age 67 is that it is now the age at which the age pension is payable. There is no longer a standard retiring age in Australia and many people work after 67. The Medical Assessor was required to assess whether Ms Wu was able to work or not. He determined that her ability to do was severely impaired.
3. In his report dated 6 June 2022, Dr Samuell considered that Ms Wu appeared to have no work capacity.
4. The evidence in the file amply supports the contention that Ms Wu is very psychiatrically unwell and that her ability to be employed is curtailed. The Medical Assessor was not in error to assess Ms Wu in class 4.

1. The Medical Assessor found that Ms Wu had a pre-existing condition and he was required to make an appropriate deduction from the impairment he assessed to reflect it.
2. Section 323 provides:

"323 Deduction for previous injury or pre-existing condition or abnormality

(1) In assessing the degree of permanent impairment resulting from an injury, there is to be a deduction for any proportion of the impairment that is due to any previous injury (whether or not it is an injury for which compensation has been paid or is payable under Division 4 of Part 3 of the 1987 Act) or that is due to any pre-existing condition or abnormality.

(2) If the extent of a deduction under this section (or a part of it) will be difficult or costly to determine (because, for example, of the absence of medical evidence), it is to be assumed (for the purpose of avoiding disputation) that the deduction (or the relevant part of it) is 10% of the impairment, unless this assumption is at odds with the available evidence...."

1. SEALS submitted that a deduction of one-tenth was at odds with the available evidence but did not make submissions as to what the appropriate deduction was. The medical evidence on which SEALS relied did not contain assessments of WPI and therefore did not engage with s 323.
2. The Guidelines specifically provide for the assessment of a s 323 deduction in respect of a psychological injury in paragraph 11.10 which provides:

"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 level. 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 1/10th of the assessed WPI."

1. Basten AJ held that the paragraph of the Guidelines was valid in Matheson v Baptistcare New South Wales & ACT (Matheson).[6]
2. SEALS relied on Marks v Secretary, Department of Communities and Justice (No 2)[7] in which Simpson AJ said that s 323 required a deduction in respect of a pre-existing condition even if asymptomatic. Her Honour also held that paragraph 11.10 of the Guidelines was inconsistent with s 323 in respect of a previously asymptomatic condition and was invalid. Basten JA disagreed with the latter finding in Matheson. The proposition that a deduction can be required in respect of an asymptomatic pre-existing condition is settled. In Vitaz v Westform (NSW) Pty Ltd[8] Basten JA, with whom the other members of the Court of Appeal agreed, rejected the contention that if a worker did not suffer symptoms from a pre-existing condition and there was no rateable impairment before an injury, there would be no deduction under s 323.
3. However, the Medical Assessor did not find that Ms Wu's pre-existing condition was asymptomatic. The pre-existing condition he diagnosed was different to that suffered as a result of the injury.

1. Member Garner said there was no evidence that Ms Wu had a contemporaneous formal psychological diagnosis or that she was referred for treatment before 2013.[9] That finding does not bind the Medical Assessor who may be required to determine questions as to the causation of an impairment.[10] The Medical Assessor determined that Ms Wu had an underlying paranoid personality disorder. The evidence on which he relied to make that diagnosis (manifested by psychological treatment on occasions between 2007 and 2013) shows that he did not consider that it was asymptomatic at the time of the injury. His diagnosis of the condition that Ms Wu developed as a result of the injury was delusional disorder, persecutory type.
2. The history set out in the evidence is relevant to determine appropriate deduction. Ms Wu had three concurrent jobs. She commenced employment with Caringbah Medical Centre as a part time blood collector in 2000 working four hours per week on weekends. She worked there until 2013. She started working for the company which became Specialist Diagnostic Services in 2000, working initially full time then for 24 hours per week from 2008. She worked there until 1 November 2015. Ms Wu began working for SEALS as a blood collector at Sutherland Hospital on 7 June 2010 working 16 hours per week and worked there until 4 March 2014.
3. Member Garner found that Ms Wu suffered a psychological injury with a deemed date of 4 March 2014. She accepted that Ms Wu had made complaints from at least February 2011 as a result of treatment by staff of SEALS and one staff member in particular. Those complaints were the subject of investigations in 2013.[11]
4. The Medical Assessor set out a history of Ms Wu's employment that substantially corresponds to Member Garner's findings and the information in the file. The Medical Assessor said:

"She obtained qualifications as an assistant in nursing and from 1994 to 2000 she worked in nursing homes as an AIN. Ms Wu obtained an AIN Certificate III in 1997. In 2000 she began working in blood collection then her daughter was born in 2001. Initially, Ms Wu worked at GLC Pathology which later changed to SDS Pathology. She was working initially full-time then part-time, 24 hours per week. In 2010 Ms Wu was working in three jobs at Sutherland Hospital, SEALS and at SDS and worked 45 hours per week combined. Ms Wu stated problems developed in 2013 as she believes she was victimised by David Matthews at SEALS. Initially, it was unclear how long she remained working at SEALS and it appeared she ceased work in 2014; however, the final termination date was noted as 2015."

1. The Medical Assessor set out his summary of Ms Wu's past psychiatric history:

"Ms Wu denied a previous history of anxiety, depression or mental health issues. However, from the Hurstville Medical Centre records, there was anxiety and depression noted dating back to 2007 reported by the general practitioner, such as on 18 December 2007, 8 July 2008 and 10 February 2009. There was stress related to a tenant in December 2012 and she was taken to St George Hospital with suicidal ideation on 29 December 2012 and the assessment reported an episode of acute situational crisis with a referral to Ms Ling, psychologist. Ms Ling initially provided a report related to depression and stress in relation to the conflict with the tenant and there was a hearing planned at the tenancy tribunal. Ms Ling later changed the emphasis from when the initial referral was made by the acute care team to incorporate workplace stress as the cause of her emotional difficulties. Therefore, there were

pre-existing and possibly paranoid ideas about the tenant harassing and threatening her and about the workplace situation potentially dating back to 2009."

"Ms Wu had experienced workplace stress before 2011 and certainly before 2013. The initial referral for psychological treatment indicated depression, suicidal ideation and perceived harassment from a tenant in 2012 while complaints and problems at work developed in 2013 when she alleged bullying and victimisation. Ms Wu then retrospectively claimed she had suffered bullying since 2011...The workplace has continually denied any responsibility for Ms Wu's alleged difficulties."

1. In the section of the MAC template specifically dealing with s 323, the Medical Assessor said that the relevant pre-existing condition was a paranoid disorder. He said that extent of the deduction as a result of that diagnosis was difficult or costly to determine so that he assessed it at one-tenth.
2. SEALS' submission that the Medical Assessor did not explain whether the characterised as an "aggravation of this pre-existing delusional disorder or some other psychiatric diagnosis" does not take account of the two diagnoses that the Medical Assessor made. In the relevant part of the MAC, the Medical Assessor said that the pre-existing condition was a paranoid disorder. He said that the current diagnosis was a delusional disorder, persecutory type, providing the relevant numerical reference in the International Statistical Classification of Diseases and Related Health Problems 10th revision (ICD 10) and in Diagnostic and Statistical Manual of Mental Disorders 5th edition, Text Revision (DSM-5-TR). Those diagnoses are different.
3. A diagnosis of a paranoid personality disorder based on the criteria in the DSM-5-TR requires a persistent distrust and suspiciousness of others, shown by the presence of four or more of the following:

"● Unjustified suspicion that other people are exploiting, injuring, or deceiving them

• Preoccupation with unjustified doubts about the reliability of their friends and coworkers
• Reluctance to confide in others lest the information be used against them
• Misinterpretation of benign remarks or events as having hidden belittling, hostile, or threatening meaning
• Holding of grudges for insults, injuries, or slights
• Readiness to think that their character or reputation has been attacked and quickness to react angrily or to counterattack, and
• Recurrent, unjustified suspicions that their spouse or partner is unfaithful."

1. Symptoms have generally begun by early adulthood.
2. A paranoid personality disorder is a different diagnosis from delusional disorder, persecutory type because of the presence of psychotic features. The Medical Assessor set out the criteria for that diagnosis:

"In summary, I formed the view Ms Wu developed a delusional disorder, persecutory type (297.1, F22) - A central theme of the delusion involves an individual's belief they are being conspired against, cheated, spied on, followed, poisoned or drugged, maliciously maligned, harassed or obstructed in the pursuit of long-term goals).

The criteria according to DSM-5-TR are outlined below:

1. The presence of delusions with a duration of one month or longer (workplace conspiracy)
2. Criterion A for schizophrenia not met

1. Apart from the impact of the delusion(s) or its ramifications, functioning is not markedly impaired and behaviour not obviously bizarre or odd

1. Not manic or major depressive episodes
2. Not due to substance use or other medical condition."

1. DSM-5-TR distinguishes delusional disorder from schizophrenia by the presence of delusions without any other symptoms of psychosis. The condition may follow a pre-existing paranoid personality disorder.

1. If the extent of the deduction is difficult or costly to determine, the assumption in s 323(2) is that the deduction is therefore one-tenth unless it is at odds with the available evidence. The Medical Assessor said that the extent of the deduction was difficult or costly to determine and made a deduction of one-tenth. The relevant criterion in this case is difficulty, rather than cost. We note that despite the extensive litigation already undertaken in respect of Ms Wu's claim, there is no other assessment of the appropriate deduction in the file, none of the practitioners who examined Ms Wu having made one. SEALS did not make submissions as to the appropriate deduction.
2. We consider that a deduction of one-tenth was the correct application of paragraph 11.10 of the Guidelines because the percentage of pre-existing impairment cannot be accurately assessed. The evidence shows that Ms Wu is very unwell and that obtaining a history from her is extremely challenging. The practitioners who saw Ms Wu at the request of SEALS agreed in 2022 that she was difficult to interview and accepted that, if not malingering, she was severely unwell and undertreated.
3. The time that has passed since the injury in 2014 contributes to the difficulty obtaining accurate information from Ms Wu. For that reason alone, the extent of the deduction is difficult to determine.
4. The temporal connection between the issue with a tenant in 2012 and the workplace events from 2011, which have been found by a Member of the Commission to have caused the injury in a decision which was not overturned on appeal, means that unravelling the role of the pre-existing disorder in the injury is difficult.
5. It is clear from the documents that Ms Wu was able to obtain and maintain three part-time jobs before the injury, that she had the capacity to engage with others and that her marriage was intact until some time after the date of the injury. We do not consider that the assumption is at odds with the available evidence.
6. The pre-existing issues highlighted in SEALS' submissions are essentially those considered and relied on by the Medical Assessor. They comprise attendances on her general practitioners in 2007, 2008 and 2009, some of which related to issues in previous employment. Difficulties with a tenant in late 2012 resulting in attendance at St George Hospital with suicidal ideation and reference soon after to a psychologist, Ms Ling.
7. The notes from Ms Ling's first consultation relate to issues with Ms Wu's tenant. From the next consultation in May 2013, Ms Wu discussed with Ms Ling her experience of workplace bullying since 2011. Ms Ling's diagnosis from that time was adjustment disorder with mixed anxiety and depressed mood due to ongoing workplace bullying.
8. In the circumstances of this case, the Medical Assessor was correct to make a deduction of one-tenth of the assessment under s 323.
9. For these reasons, we have determined that the MAC issued on 24 February 2025 should be confirmed.

[1] Wu v State of New South Wales (Southern NSW Pathology Service) [2023] NSWPIC 583 (Member Decision).

[2] State of New South Wales (Southern NSW Pathology Service) v Wu [2024] NSWPICPD 76.

[3] [2006] NSWCA 284.

[4] [2021] NSWCA 304 at [26].

[6] [2025] NSWSC 213.

[7] [2021] NSWSC 616.

[8] [2011] NSWCA 254 at [43].

[10] Bindah v Carter Holt Harvey Woodproducts Australia Pty Ltd [2014] NSWCA 264 at [109]- [111].