SUN MING LOK, A MINOR SUING BY HIS MOTHER AND NEXT FRIEND, HUI MAN CHONG v. CHOY WING HO AND ANOTHER

HCPI 200/2017

[2021] HKCFI 852

IN THE HIGH COURT OF THE

HONG KONG SPECIAL ADMINISTRATIVE REGION

COURT OF FIRST INSTANCE

PERSONAL INJURIES ACTION NO 200 OF 2017

________________________

________________________

DECISION

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I. INTRODUCTION

1.  The 1^st defendant (“D1”) was a specialist in paediatrics employed by the 2^nd defendant (“D2”). In/about March 2014, the plaintiff (“P”), then 2 years old, was a patient of D1 and/or D2 who were employed/engaged to provide medical care and treatment for him.

2.  On 24 February 2017, P commenced the present action against D1 for personal injury, loss and damages suffered as a result of medical negligence when P was under D1’s medical care and management in March 2017. On 12 June 2018, leave was granted for P to join D2 as the 2^nd defendant in the present action. On 25 June 2018, P re-filed the Amended Writ of Summons that named D1 and D2 respectively as the 1^st and 2^nd defendants.

3.  For the present purpose, it is unnecessary to go into to all details of the parties’ allegations and counter-allegations in the present action. I gratefully adopt the useful summary in the written submissions of Mr Lam SC, senior counsel for D1 and D2 (collectively, “Ds”), that set out the relevant background:

“3. Putting aside differences between the parties which cannot be dealt with in an interlocutory application, the relevant facts may briefly be summarized as follows: ……

(a) [P] was unwell from 8 to 10 March 2014. On 10 March 2014, he consulted Dr Wu Chun Bon, a Specialist in Paediatrics, at the Out-Patient Department (‘OPD’) of [D2]. Dr Wu’s diagnosis was pharyngitis.

(b) On 12 March 2014, [P] consulted [D1] at the OPD of [D2]. [D1] admitted [P] to [D2] as he had fever for 4 days without significant improvement.

(c) Upon admission, [D1] ordered that [P] to receive, inter alia, intravenous Claforan (an antibiotic for treatment of bacterial infection). Further tests were arranged. His preliminary diagnosis was pharyngitis.

(d) Between 13 and 14 March 2014, [P] continued to suffer various symptoms. [D1] maintained the diagnosis of pharyngitis.

(e) On 15 March 2014 at about 6:40pm, [D1] examined [P’s] abdomen and recorded that it was distended. [D1] stated that it was only slightly distended which was not uncommon for a sick child who had resumed feeding.

(f) On 16 March 2014, [P] continued to suffer from swinging high fever. [D1] prescribed a more broad-spectrum antibiotic for treating a variety of bacterial infections.

(g) On 17 March 2014 at about 6:40pm, [D1] examined [P] and found that he had developed abdominal distensions. Abdominal ultrasound scan to check whether [P] had intra-abdominal sepsis or other possible underlying conditions was arranged for the next morning.

(h) At about 10:00pm, [D1] was informed that [P] vomited greenish fluid and his blood test showed abnormal findings. [D1] ordered an urgent CT scan which was done at about 11:25pm.

(i) The CT scan report released at about 1:15am on 18^th March 2014 revealed that gross ascites were present with associated pneumoperitoneum (indicative of perforated hollow viscus), intestinal obstruction was evident with generalized small bowel dilation and fluids levels, and a suspected focal mural defect was seen at the sigmoid colon which might represent the site of perforation.

(j) [D1] explained the CT findings to the parents and referred [P] immediately to undergo urgent surgical intervention at the Department of Paediatrics in Queen Elizabeth Hospital (‘QEH’).

(k) At about 2:45am, [P] was transferred to QEH and underwent emergency operation. The operative diagnoses were pneumoperitoneum, colitis and intra-abdominal abscess. He underwent the Hartmann’s operation involving the resection of the descending colon down to upper rectum.”

4.  P claimed that during his stay at D2 on 13-17 March 2014 he suffered from gastrointestinal symptoms, and that in particular he developed abdominal distension on 15 and 17 March 2014. By a referral letter dated 18 March 2014 (“Referral Letter”), D1 sought intervention from a surgeon at QEH as follows: “In view of acute gut perforation, urgent surgical consultation for intervention is to be anticipated. Your expert management will be much appreciated”.

5.  Mr Tsoi, counsel for P, submitted that for the purpose of the Appeal referred to in paragraph 27 below, “it is P’s case that …… (1) D1 failed to make timely referral to a paediatric surgeon in view of P’s gastrointestinal symptoms thereby depriving P of gaining a very substantial recovery to his pre-incident condition; (2) Earlier investigation and intervention of P’s gastrointestinal symptoms would have prevented P from suffering from intestinal obstruction and/or gut perforation”.

6.  Ds disputed liability, denied any delay in diagnosis and/or delay in referral, and put P to proof of his allegations.

II.  PLEADINGS

7.  According to the Statement of Claim filed on 9 July 2018 (“SoC”), P pleaded that “[D1] was a Specialist in Paediatrics who was employed by [D2] and provided medical and specialist services at [D2]”. This was echoed in the Defence filed on 27 November 2018 that averred “[D1] was, at all material times, employed by [D2] as a Resident Specialist in Paediatrics”.

8.  On the issue of liability, P’s case of negligence and/or breach of contract against D1 and/or D2, their servants and their agents as pleaded in paragraph 23 of the SoC was premised on alleged delay in diagnosis and alleged delay in referral. P gave particulars of Ds’ wrongdoings in paragraph 23 of the SoC, and averred Ds’ alleged delay in referral inter alia as follows:

(a)	failing to have P re-examined by more experienced medical staff and/ or surgeon capable of making the diagnosis;
(b)	failing to refer P to an abdominal surgeon, paediatric surgeon, suitable specialist and/or other qualified member of the medical staff to examine P’s condition and/or his abdomen forthwith;
(c)	failing to cause P to be examined by a surgeon and/or admitted to hospital such as QEH for full investigation and/or surgical intervention until 18 March 2014 (P came under D1’s medical care and treatment since 12 March 2014);
(d)	failing to arrange the admission of P to a hospital such as QEH in sufficient time for emergency treatment to be performed before 17 March 2014;
(e)	failing to refer to essential surgery in time, thereby depriving P of the opportunity of gaining a very substantial recovery and/or a more complete restoration to his pre-incident condition.

9.  Ds denied liability and averred inter alia as follows:

(a)	on 13 March 2014, P had 4 times watery stool but there was no blood, no bile-stained vomitus, and P’s abdomen was soft and he was active and playful;
(b)	on 14 March 2014, P had several loose stool but again there was no blood in it;
(c)	there was nothing on 13-14 March 2014 to alert of the possibility of any surgical emergencies;
(d)	on 15 March 2014, D1 examined P in the morning and found his abdomen was soft and non-tender, and in the evening P’s abdomen became slightly distended but still soft with bowel sounds present; and P had improved feeding and good urine output;
(e)	on 16 March 2014, P’s fever persisted with no other abnormal physical signs, and D1 changed the antibiotics to Meropenem (of wider spectrum than previous antibiotic Cefotaxime); there were 3 times loose stool that day with no blood; there was no suggestion of surgical emergencies, and referral for a second opinion from other specialists at this juncture was not indicated;
(f)	at/about 6:40pm on 17 March 2014, D1’s examination revealed no guarding or rebound tenderness in the distended abdomen, so D1 proceeded to arrange an ultrasound abdomen to be done the next morning (which was acceptable), but there was no indication for surgical intervention or exploratory laparotomy at this point;
(g)	it was likely that P’s gut perforation occurred sometime between 6:40pm and 10:00pm on 17 March 2014 as his condition changed with bilious vomiting, feeding intolerance and a tense distended abdomen, and the gut perforation caused pneumoperitoneum, which would not be seen on any abdominal radiograph taken before the gut perforation;
(h)	P’s clinical course was compatible with infectious colitis evolving into toxic megacolon and then gut perforation and peritonititis, and the antibiotics prescribed to P (ie Cefotaxime and later changed to Meropenem) were effective against bacteria commonly found in the gut;
(i)	to opine that other forms of treatment instituted in any other time frame would change the natural course of the disease was speculative as P suffered from infective colitis and was already prescribed with strong and broad spectrum antibiotics (Cefotaxime and then Meropenem), which were for serious infections and not just pharyngitis;
(j)	a CT scan abdomen was only indicated when P’s condition changed sometime between 6:40pm and 10:00 pm on 17 March 2014; after D1 saw P at/about 10:30pm, a CT scan was urgently arranged; after the CT scan was performed and the report was released at/around 1:15am on 18 March 2014, D1 promptly informed the parents of the CT findings at/around 1:30am, explained that urgent surgical intervention with paediatric ICU care was required, and advised that P be immediately transferred to QEH for further management (since QEH had paediatric ICU support); then referral was made with the parents’ consent; hence, there was no delay.

10.  On the issue of causation, P at paragraph 28 of the SoC pleaded that “[for] the avoidance of doubt, [P’s] case as to causation will be that earlier investigation and intervention of [P’s] gastrointestinal symptoms would have prevented [P] from suffering intestinal obstruction, gut perforation and/or pneumoperitoneum”. Ds in paragraph 37 of their Defence denied such averment, and reiterated the averment in paragraph 9(i) above.

III.  WITNESS STATEMENTS

11.  P’s factual witnesses were his parents. The contents of paragraph 19 of the witness statement of P’s father dated 24 April 2019 and those of paragraph 18 of the witness statement of P’s mother dated 25 April 2019 were almost identical. For present purpose, it is sufficient for me to set out paragraph 18 of the witness statement of P’s mother as follows:

“18. 我認為[D1]在2014年3月12日至2014年3月18日治療[P]期間, 涉及醫療疏忽, 包括但不限於:

(a) [D1]未能及時正確診斷[P]的腸塞及腸穿情況, 多日都堅持[P]只是患了咽喉炎;

(b) 經多次反映[P]的嘔吐及腹瀉症狀後,[D1]仍沒有為[P]進行適當及足夠的檢查和治療, 亦沒有轉介[P]給適當的醫生或腸胃科醫生, 延誤診斷及治療;

(c) [D1] 對於[P] 的嘔吐及腹瀉症狀警覺性極低, 直至住院六天後深夜才安排[P]接受CT掃描檢查。”

IV.  PROCEDURAL HISTORY

12.  By a letter dated 9 March 2018, P’s solicitors (“PSols”) informed the solicitors for D1 (who was the only defendant at that time) (“D1Sols”) that his expert on liability was Prof PT, “specialist in Paediatric Surgery” (my emphasis). By a letter dated 12 March 2018, D1Sols noted P’s liability expert was Prof PT, and asked for a copy of his expert report as soon as it was ready.

13.  On 25 May 2018, P filed a summons to seek directions inter alia to join D2 as the 2^nd defendant, and to file/serve “his expert report on liability and causation” (my emphasis). By a letter dated 8 June 2018, D2’s former solicitors wrote to inform PSols that D2 would consent to P’s summons subject to P paying D2’s costs of the application. By a letter dated 11 June 2018, D1Sols wrote to inform PSols D1 had no objection to the directions sought in P’s summons. By the order of Master M Lam dated 12 June 2018, P was directed to file/serve inter alia his SoC and “expert report on liability and causation prepared by [Prof PT], a paediatrist” (my emphasis). However, there was no dispute that Prof PT was a paediatric surgeon rather than a paediatrician.

14.  On 9 July 2018, P filed his SoC and Prof PT’s 1^st expert report dated 1 June 2018 (“PT 1^st Report”). Paragraph 23 of the PT 1^st Report stated inter alia that “[on] a balance of probabilities, one has to conclude that [D1] had fallen below the requisite standard of care in the ways listed in 7(a-g) in [PSols’] instructions ……” So by a letter dated 11 July 2018, D1Sols wrote to PSols, referring to paragraph 23 of the PT 1^st Report and asking for copy of PSols’ instructions to Prof PT. By a letter dated 11 July 2018, PSols replied by asserting litigation privilege and refusing to disclose their instructions to Prof PT. By a letter dated 12 July 2018, D1Sols argued such instructions were not privileged, and pressed for a copy thereof in order to understand what Prof PT meant when he claimed D1 “had fallen below the requisite standard of care in the ways listed in 7(a-g) of [PSols’] instructions”. By a letter dated 20 July 2018, PSols sent to D1Sols a redacted copy of paragraph 7(a)-(g) of their letter of instructions to Prof PT:

“7. We hereby instruct you to prepare a report with regard to the aforementioned matters and ask you to specifically advise whether, on a balance of probabilities, [D1] had fallen below the requisite standard of care in the following ways:

(a) Insisting that [P] was only suffering from pharyngitis during his stays at [D2], without correcting diagnosing his condition and recommending proper treatment;

(b) Failing to conduct any or any sufficient and/or proper follow-up assessment and/or treatment on [P] even after symptoms of vomiting and diarrhea were observed;

(c) Failing to refer [P] to a more senior doctor or gastrointestinal specialist even after symptoms of vomiting and diarrhea were observed;

(d) Failing to conduct any or any sufficient and/or proper follow-up assessment and/or treatment on [P] after abdominal distension was observed;

(e) Failing to refer [P] to a more senior doctor or gastrointestinal specialist after abdominal distension was observed;

(f) Failing to remain alert to [P’s] medical condition during his 6 days at [D2];

(g) Failing to arrange any or any proper medical examination of [P’s] condition until his 6^th night at [D2], whereby a CT scan of the abdomen was carried out late at night;

……”

15.  The parties filed their respective PI Questionnaires (“PIQs”) for the 1^st Checklist Review (“CLR”) hearing scheduled to be heard on 28 August 2018:

(a)	P’s PIQ filed on 16 August 2018 confirmed Prof PT was P’s expert on liability in the field of paediatric surgery to address on the expert issue of whether D1’s clinical management of P was negligent and fell below “the requisite standard of care”;
(b)	D1’s PIQ filed on 20 August 2018 stated D1’s expert on liability in the field of paediatrics (identity yet to be confirmed) would address on the expert issue of whether D1’s management of P fell below “the standard expected of a Specialist in Paediatrics”;
(c)	D2’s PIQ filed on 14 August 2018 stated D2 did not intend to adduce expert evidence on liability at trial “subject to steps taken during the course of the proceedings which concern [D2]”.

16.  By a Consent Summons filed on 21 August 2018, the parties agreed inter alia to extension of time until 2 October 2018 for each of Ds to file/serve his/its Defence with an expert report on liability and causation (if any). By the order of Master Roy Yu dated 28 August 2018, leave was granted for P “to adduce expert evidence on liability by a paediatric surgeon, namely [Prof PT]” and for D1 “to adduce expert evidence on liability by a paediatrician” (my emphasis), but D2 elected not to adduce expert evidence on liability.

17.  On 27 November 2018, D1 served the expert report dated 7 September 2018 by Dr CHB (“CHB Report”). There was no dispute that Dr CHB was a paediatrician and not a paediatric surgeon.

18.  A CLR hearing was scheduled on 29 January 2019:

(a)	Ds’ PIQ filed on 22 January 2019 confirmed D1’s expert on liability was Dr CHB in the field of paediatrics, and Ds did not intend to take out other interlocutory applications at this stage;
(b)	P’s PIQ filed on 28 January 2019 confirmed Prof PT was P’s expert on liability in the field of paediatric surgery to address on the expert issue of whether D1’s clinical management of P was negligent and fell below “the requisite standard of care”.

19.  By the order of Master Roy Yu dated 29 January 2019,

(a)	P was to cause Prof PT to produce an expert report in reply to the CHB Report described as “the expert report on liability and causation prepared by the 1st and 2nd defendants’ expert, [Dr CHB], dated 7 September 2018” (my emphasis);
(b)	the parties were to cause their liability experts, ie Prof PT for P and Dr CHB “for the 1st and 2nd defendants” (my emphasis) to have a meeting on without prejudice basis to identify the matters on which they agree and disagree;
(c)	the parties were to cause Prof PT and Dr CHB to produce a joint statement (i) identifying the matters they agree and (ii) identifying the matters on which they have failed to reach common opinion and the reasons for their disagreement;
(d)	medical expert evidence on quantum was limited to 1 paediatric expert for each party (ie Dr CPT for P and Dr TWTP for Ds), and 1 paediatric surgery expert for each party (ie Prof PT for P and Dr TYH for Ds).

20.  On 2 May 2019, P filed/served Prof PT’s 2^nd expert report (“PT 2^nd Report”).

21.  By a letter dated 3 June 2019 (“3/6/19 Letter”), Ds’ solicitors (“DSols”) wrote to PSols objecting to the admissibility of Prof PT’s expert evidence given from the perspective of a specialist in paediatric surgery. DSols complained that the PT 2^nd Report never said D1’s management of P fell below the standard expected of a reasonable specialist in paediatrics, and instead it showed Prof PT gave expert opinion and criticised D1 from the perspective of a specialist in paediatric surgery, which DSols claimed was not the correct approach since D1’s management should be judged on the standard of a reasonable specialist in paediatrics.

22.  By a reply letter dated 21 June 2019, PSols disagreed and enclosed Prof PT’s letter dated 14 June 2019 (“PT 1^st Letter”) that explained there were overlaps, synergies and differences between the 2 specialties of paediatrics and paediatric surgery, and that in any event Prof PT possessed the relevant qualifications/training to comment on the standard of care of a paediatrician such as D1.

23.  As seen above, whilst there was no dispute Prof PT and Dr CHB were the parties’ nominated experts, there was some confusion in the expert directions as to whether (a) such experts were to render expert reports on the issue of liability or on the issues of liability and causation, (b) the court-permitted expert discipline for the issue(s) of liability or liability and causation was paediatrics or paediatric surgery, and (c) Dr CHB was the nominated expert for D1 or for Ds.

V. SUMMONS AND APPEAL

24.  On 3 October 2019, Ds filed a summons for the following reliefs (“Summons”):

(a)	the PT 1st/2nd Reports be withdrawn and shall not be adduced at the trial of the present action;
(b)	costs of such application be to Ds in any event.

25.  On 3 October and 20 December 2019, Ds filed the 1^st and 2^nd affidavits of their solicitor Chan Wai Chung William (“Chan”) in support of the Summons (“Chan 1^st and 2^nd Affs”). On 25 November 2019, P filed the affirmation of his solicitor Hui Chun (“Hui”) to oppose the Summons (“Hui Aff”).

26.  On 16 January 2020, Master Roy Yu dismissed the Summons with costs to P with certificate for counsel and P’s costs to be taxed in accordance with Legal Aid Regulations (“Master Order”). The learned master also directed the parties to jointly report to the court within 28 days on (a) the admissibility of the PT 1^st Letter and Prof PT’s letter dated 20 November 2019 referred to in paragraph 32 below (“PT 2^nd Letter”), and (b) time extension (if required) for complying with previous case management directions.

27.  On 24 January 2020, Ds filed their Notice of Appeal against the Master Order for an order that (a) the Master Order be set aside, (b) the PT 1^st/2^nd Reports be withdrawn and not be adduced at the trial of the present action, and (c) P to pay Ds costs of and occasioned by the Summons (including costs of the hearing before Master Roy Yu on 16 January 2020) and costs of the appeal with certificate for counsel (“Appeal”). The Appeal came before this court for hearing on 19 January 2021 (“Hearing”).

VI. PARTIES’ RESPECTIVE STANCE

28.  Ds claimed the PT 1^st/2^nd Reports ought to be withdrawn since Prof PT belonged to the wrong specialty and/or applied the wrong standard in such expert reports. On the other hand, P claimed inter alia that:

(a)	the difference between the specialties of paediatric surgery and paediatrics was only relevant to the question of weight and not as to admissibility, and “[Prof PT] (whose opinion represents the body of Paediatric Surgeons but also skilled in practice of Paediatricians) had correctly applied the Bolam test” (my emphasis);
(b)	the expert evidence of Prof PT (a paediatric surgeon) served the dual purpose of establishing liability and causation, and on the issue of causation the court was likely to attribute more weight to the opinion of a paediatric surgeon than that of a paediatrician.

VII. PT 1^ST/2^ND REPORTS AND PT 1^ST/2^ND LETTERS

29.  PT 1^st Report  In the PT 1^st Report, Prof PT first set out his qualifications as an expert. His stated professional qualifications, work experience, academic positions, professional journal editorial board positions, and positions in medical association/society in Hong Kong and abroad for over 30 years were in paediatric surgery. Then Prof PT set out the “Medical Summary” followed by his “Expert opinion” inter alia as follows:

“……

21. In reviewing the course of [P’s] illness and the management at [D2], based on the available medical records, my view is that [D1] had been preoccupied with the diagnosis of pharyngitis and had not seriously considered alternative diagnosis or concurrent development of a medical condition to account for the patient’s unresolved fever and his gastrointestinal (GI) symptoms. While GI symptoms in a child can be non-specific and related to any systemic illness, the persistence of those clinical features should alert a competent doctor to an underlying GI conditions which warrants further investigations and/or referral for a specialist opinion.

22. Despite the findings of a congested throat, there had been no viral or bacterial confirmation of pharyngitis which was intractable to a lengthy course of antibiotic treatment. The persistent swinging fever and elevated CRP and WBC and neutrophil counts on 12.3.2014 and 17.3.2014 pointed to persistent sepsis. Together with persistence of GI symptoms, these should have caused sufficient concerns for a second opinion in determining the cause of illness of the child.

23. On a balance of probabilities, one has to conclude that [D1] had fallen below the requisite standard of care in the ways listed in 7(a-g) in [PSols’] instructions. Insisting that the minor was only suffering from pharyngitis during his 6 days stay at [D2] and only included ‘Abdominal distension for workup’ in the diagnosis on 17.3.2014 at 18.00 had resulted in delay in the diagnosis of colitis and possible avoidance of gut perforation.

……

29. It is an unfortunate medical event that may have been prevented/ameliorated by an earlier diagnosis. The diagnosis is not easy or straightforward as fever is a non-specific symptom which can be caused by many conditions and a young child is unable to communicate specific symptoms such as possible abdominal pain which would have alerted the physician to an abdominal disease. It is not unreasonable for primary physicians to treat a patient for common diseases. Upper respiratory tract infection is indeed a common cause of childhood fever. Nevertheless, when the fever did not respond to empirical treatment and when there were additional (vomiting and diarrhea) and evolving (abdominal distension) symptoms, coupled with laboratory evidence of ongoing sepsis (infection), it would be reasonable to expect a referral for a second opinion or more investigations. Specifically by 15.3.2014 evening when the child had abdominal distension, an abdominal imaging study should have been ordered. The child should have been re-examined carefully for additional signs on 16.3.2014 and by 17.3.2014, a second opinion could have been sought. Instead of awaiting for an ultrasound examination on 17.3.2014, a simple AXR (erect and supine) would have pointed to bowel obstruction/distension leading to an earlier CT scan and transferred to QEH.

30. Earlier diagnosis may result in avoidance of surgery or less extensive surgery. If the diagnosis of colitis has been suspected or diagnosed on 13, 14 or 15.3.2014, complete bowel rest, adequate intravenous fluid and electrolyte replacement, sepsis work up, repeated blood and stool tests and appropriate antibiotics may slow or reverse the progression from simple colitis to advanced colitis complicated by bowel necrosis and perforation. Even if diagnosis of colitis could only be reached by 16.3.2014 or early 17.3.2014, by which time the gastrointestinal features were much more evident, bowel necrosis may be less extensive and less bowel may need to be resected. Avoidance of bowel perforation for earlier surgery could also result in less short- and long-term morbidity such as future risk of intestinal adhesions.

……” (my emphasis)

30.  PT 2^nd Report  Prof PT reviewed the CHB Report and then gave the PT 2^nd Report in reply as follows:

“……

6. I will now turn to [Ds’] expert opinions. In [the PT 1^st Report], one would find that I have some understanding of how [D1] managed [P] up to 15/3/2014 evening and how he arranged expert care once the diagnosis was made. Hence I do not believe he had been uncaring nor irresponsible. My main concern has been the delay in seeking extra investigations/ expertise when sepsis was unresponsive to empirical treatment, when the source of sepsis was unidentified and when there were new symptoms. I would also accept that one is often wiser in retrospect and therefore one can understand to some extent the difficulties leading to the delay in diagnosis.

7. However, the key factors which contributed to the unsatisfactory clinical outcome need to be addressed.

8. There is a difference between [Ds’] expert and me in the approach towards new abdominal signs and symptoms in the presence of sepsis of unknown origin which had been unresponsive to empirical treatment, Abdominal distension is considered a serious clinical feature by surgeons (like me) whereas [Ds’] expert (a paediatrician) focused more on the abdomen being soft and the presence of bowel sounds as reassuring clinical features. This is the basis of his justification for neither seeking additional expert opinion nor undertaking additional appropriate tests promptly. Surgeons are trained to manage abdominal emergencies and are risk-averse: even small probability of a high risk is taken seriously.

9. Abdominal distension was first noted on 15/3/2014 (see above comments on paragraph 18 of the Defence) and again on 17/3/2014 9:35 a.m. (though this was somehow left out in paragraph 22 of the Defence) …… [Ds’] expert pointed out in paragraph 22 of his report that ultrasound abdomen was ordered at 6:40 p.m. on 17/3/2014 to look out for possible underlying conditions and surgical conditions like intussusception or volvulus and yet arranged the study to be done the next morning and felt this delay was justified (paragraph 52). The surgical consensus would be that surgical conditions like impending gut perforation, intussusception and volvulus are surgical emergencies which cannot be delayed by over 12 hours. Events had proven that the conclusion of ‘Need for surgical intervention or exploratory laparotomy was quite unlikely’ was not well founded.

10. While abdominal ultrasonography is helpful for specific conditions of intra-abdominal sepsis such as intra-abdominal abscess, appendicitis, urological and solid organ pathologies, and intussusception, it cannot replace the simple abdominal x-ray in the diagnosis and evaluation of progression of intestinal pathologies such as intestinal obstruction, toxic megacolon and perforation.

……

14. I agree with [Ds’] expert report at paragraph 42 that the gut perforation likely happened sometime between 6:40 p.m. and 10:00 p.m. The clinical window to detect serious gut pathology (toxic megacolon) before the gut perforation was however not fully made use of: While there are mitigating factors to argue for a more lenient interpretation of the clinical events (see my medical report earlier), the clinical outcome remains unsatisfactory for the patient.

15. If there was more alertness to the serious consequences of delay in the diagnosis and management of progression of toxic megacolon to intestinal perforation, there may be more urgency in investigation and surgical consultation.

16. That sense of urgency would probably also allow [D1] to diagnose intestinal perforation earlier than to wait CT scan report at 1:15 a.m. on 18/3/2014. It should be within a paediatrician’s clinical expertise to recognize pneumoperitoneum either on an erect AXR or CT scan soon after [P] was seen again at 10:30 p.m.

……

17. …… With intellectual disabilities, [P’s] ability to communicate with the Paediatrician may be diminished but abdominal distension is a sign, not a symptom dependent on a child’s communication. Hence this factor would not influence the Paediatrician’s ability to arrange an earlier abdominal XR, ultrasound examination or surgical consultation outlined above. With increased risk of infection, one may argue that the Paediatrician should have heightened awareness of disease progression and complication (toxic megacolon and perforation) and have more urgency in arranging the investigations and consultation.” (my emphasis)

31.  PT 1^st Letter  As a result of the 3/6/19 Letter (see paragraph 21 above), PSols sought clarification from Prof PT who gave the PT 1^st Letter dated 14 June 2019 as follows:

“(1) What are the differences between paediatric medicine and paediatric surgery?

Both specialties provide specialty health care of infants and children. Paediatrics is a medical specialty, whereas paediatric surgery is a surgical specialty. Illnesses do not recognize specialties, humans do. There are overlaps, synergies and differences between the two specialties. Each should know sufficiently the other to be able to provide seamless care.

(2) Whether the training of a pediatric surgeon already covers that of a paediatrician?

The training of paediatric surgery requires essential knowledge of paediatrics. Both share common knowledge of physiology and pathologies of infants and children though the foci and depths may differ. The current President of Hong Kong Society of Paediatrics is Dr [NC], a paediatric surgeon. Drs [PY] and [KL], both paediatric surgeons, have also served in this leadership position.

(3) Whether you, as a specialist in paediatric surgery, have the relevant qualifications and training to comment on the standrard of care of a paediatrician.

I am a Fellow of Royal College of Paediatrics and Child Health (FRPCH). I have been examiner of MBChB Paediatrics (U of Liverpool), and Diploma of Child Health (UK). I interact with paediatricians on a daily basis in my professional practice. I consider myself to possess the relevant qualifications and training to comment on the standard of care as [D1] in this case.” (my emphasis)

32.  PT 2^nd Letter  Upon review of the Chan 1^st Aff, PSols sought further clarification from Prof PT who gave the PT 2^nd Letter dated 20 November 2019 as follows:

“(1) According to [PT 1^st Letter], you stated that “each [discipline] should know sufficiently the other to be able to provide seamless care … though the foci and depths may differ.” With reference to paragraph 9 of [PT 2^nd Report], whether [D1] as a paediatrician ought to have known of the “surgical consensus … that surgical conditions like impending gut perforation, intussesception and volvulus are surgical emergencies which cannot be delayed by over 12 hours”?

Answer (1): “Impending gut perforation … are surgical emergencies …” is both a surgical consensus and knowledge expected of qualified medical practitioners including paediatricians.

(2) According to paragraph 8 of [PT 2^nd Report], you stated that “[Ds’] expert (a paediatrician) focused more on the abdomen being soft and the presence of bowel sounds as reassuring clinical features.” In view of the abdominal distension in the present case:

(1) Irrespective of the “focus” of the two disciplines, whether a paediatrician such as [D1] is equally “trained to manage abdominal emergencies” and therefore ought to be “risk-averse”?

(2) Whether the reliance of these clinical features by [D1] as “reassurance” fell below the standard of a reasonably competent paediatrician in all the circumstances of the present case?

Answer (2): A paediatrician is trained in both the medical curriculum and clinical training to manage abdominal emergencies and is expected to make appropriate referrals to relevant specialists for serious conditions requiring treatment outside his/her capabilities. From my perspective as a specialist who gets referrals from medical practitioners and paediatricians for abdominal emergencies, this referral is relatively late in comparison with other referring doctors when faced with similar clinical features. Accordingly, [D1’s] actions fell below the standard of a reasonably competent paediatrician in the aspect of timely referral to a relevant specialist.

……

(4) Please elaborate your reference to Dr [NC], Dr [PY] and Dr [KL] in answer to the question posed in the [PT 1^st Letter], namely, whether the training of a paediatric surgeon already covers that of a paediatrician?

Answer (4): The names that I referred to are merely examples of more well-known paediatric surgeon who possessed the knowledge and practice of both paediatrician and paediatric surgeon. The training of a paediatric surgeon covers his/her professional relationship with other relevant specialties including paediatrics. A reasonably competent paediatric surgeon should know when to refer his/her patient to a paediatrician and vice-versa.

(5) Please provide documents and/or elaboration on your experiences as “examiner of MBChB Paediatrics (U of Liverpool)” in answer to the question posed in the [PT 1^st Letter], namely, whether you have the relevant qualifications and training to comment on the standard of care of a paediatrician?

Answer (5): I had been an examiner in Paediatrics in the final MCBhB curriculum in 1988 when I was Senior Lecturer (Paediatric Surgery) in the Institute of Child Health. I was also an examiner in Diploma of Child Health (UK) held in Hong Kong in the late 1990’s.

……

(7) In response to paragraph 19 and 30 of the [Chan 1^st Aff], whether “the requisite standard of care” under paragraph 23 of [PT 1^st Report] refers to the standard of care expected of a reasonably competent paediatrician?

Answer (7): “The requisite standard of care” under paragraph 23 of [PT 1^st Report] refers to the standard of care expected of a reasonably competent paediatrician in the aspect of timely referral.

(8) With reference to paragraph 30 of [PT 1^st Report] that “earlier diagnosis may result in avoidance of surgery or less extensive surgery …”, whether your expertise as a paediatric surgeon is more appropriate than that of a paediatrician to comment on the issues of causation arising from [D1’s] delay of proper diagnosis?

Answer (8): “Earlier diagnosis may result in avoidance of surgery or less extensive surgery …” is a medical knowledge expected of a reasonably competent medical practitioner, irrespective of whether he/she is a paediatric surgeon or paediatrician. As a specialist in surgery, a paediatric surgeon has more experience in the entire spectrum of early to late diagnosis and its consequences.” (my emphasis)

VIII.  CHAN 1^ST AND 2^ND AFFS

33.  Chan said in applying the Bolam test, ie a doctor is not guilty of negligence if he has acted in accordance with a practice accepted as proper by a reasonable body of medical men skilled in that particular art, one needs to refer to the standard of a reasonable specialist in the particular discipline. Here, D1 was a specialist in paediatrics, but Prof PT was a specialist in paediatric surgery.

34.  Chan explained that in Hong Kong “paediatrics” and “paediatric surgery” were 2 distinct/separate medical specialties, and specialists in paediatrics and specialists in paediatric surgery were registered under different specialist registers of the Medical Council of Hong Kong(“MCHK”). Further, “paediatrics” (ie The Hong Kong College of Paediatricians) was 1 of 15 constituent colleges of the Hong Kong Academy of Medicine (“HKAM”),[1] but “paediatric surgery” was not a constituent college of HKAM and instead it was one of the specialty boards of The College of Surgeons of Hong Kong.[2]

35.  Paragraph 23 of the PT 1^st Report commented “[D1] had fallen below the requisite standard of care ……” and criticised various aspects of D1’s management (see paragraph 29 above), but there was no explanation as to what the “requisite standard of care” was. On the contrary, Dr CHB in the CHB Report opined on D1’s management of P, and concluded in paragraph 58 thereof it was “appropriate and did not fall below the standard expected of a Specialist in Paediatrics in Hong Kong”, ie Dr CHB expressly judged D1’s management according to the standard expected of a specialist in paediatrics in Hong Kong.

36.  Prof PT prepared the PT 2^nd Report in response to the CHB Report, but he did not expressly state D1’s management fell below the standard of a reasonable specialist in paediatrics. Chan claimed Prof PT viewed the present case and gave expert opinion from the perspective of a specialist in paediatric surgery as evident from paragraph 8 thereof. Chan claimed the parts of paragraph 8 of the PT 2^nd Report as italicised and underlined in paragraph 30 above showed Prof PT acknowledged he and Dr CHB held different opinion over D1’s medical management of P because they were in different specialties, and in particular:

(a)	Prof PT described himself as a “surgeon” and described Dr CHB as a “paediatrician”;
(b)	Prof PT explained surgeons and paediatricians saw things differently from a medical perspective and focused on different clinical features, ie surgeons would treat P’s abdominal distension as a serious clinical feature whereas paediatricians would focus on P’s other clinical features such as soft abdomen and presence of bowel sounds.
(c)	Prof PT explained surgeons and paediatricians were trained differently, and therefore managed abdominal emergencies differently, ie surgeons were risk-averse and would take a small probability of risk seriously, the implication being paediatricians would take a small probability of risk less seriously.

Prof PT in paragraph 9 of the PT 2^nd Report also referred to the surgical consensus or standard of care (see paragraph 30 above).

37.  Chan said these remarks by Prof PT “rang alarm bells for [Ds]”, which led to the 3/6/19 Letter whereby DSols raised concerns about Prof PT giving expert opinion from the perspective of a specialist in paediatric surgery (rather than that of a specialist in paediatrics) (see paragraph 21 above). In response PSols obtained the PT 1^st Letter, but Chan noted such letter simply gave Prof PT’s own view that he had the necessary qualifications, training and knowledge in paediatrics to comment on D1’s management, but did not address Ds’ real concerns that Prof PT used the wrong standard of a specialist in paediatric surgery or otherwise viewed this case from the perspective of a specialist in paediatric surgery in criticising D1’s management. Indeed, Prof PT in the PT 1^st Letter again described the 2 specialties differently, ie paediatrics was a “medical” specialty and paediatric surgery was a “surgical” specialty.

38.  Chan claimed D1’s management should be judged against the standard of a reasonable specialist in paediatrics in Hong Kong, which was why Ds nominated Dr CHB, a specialist in paediatrics, as expert. Although Ds accepted (a) there were probably overlaps and synergies between the 2 specialities both of which concerned children (as suggested in Answer (1) of the PT 1^st Letter), and (b) Prof PT had previously obtained some relevant UK qualifications in paediatrics (as suggested in Answer (3) of the PT 1^st Letter), Chan claimed that having some relevant qualifications in paediatrics from the United Kingdom would not necessarily mean Prof PT had the necessary expertise to comment on the management of a specialist in paediatrics in Hong Kong. In any event, Ds’ main concern was not that Prof PT lacked necessary knowledge in paediatrics but rather he used the wrong standard to criticise D1’s management (as evident from paragraph 8 of the PT 2^nd Report where he plainly adopted the standard of a specialist in paediatric surgery to explain why, in his view, D1 should have acted on the finding of abdominal distension – see paragraph 30 above). Indeed, Prof PT even implied Dr CHB held a different view because he was a paediatrician rather than a paediatric surgeon.

39.  Further, Chan pointed out that a key allegation of medical negligence herein was D1’s failure to order further investigations and/or to refer P for specialist opinion when P had abdominal distension in the evening of 15 March 2014. Chan noted the Hui Aff seized on paragraph 29 of the PT 1^st Report that asserted “[it] is not unreasonable for primary physicians to treat a patient for common diseases” (see paragraph 29 above) and other remarks in the PT 1^st Report to argue Ds had read Prof PT’s expert opinion in the PT 1^st Report out of context. But Chan said that upon careful review, paragraph 29 of the PT 1^st Report explained that Prof PT’s key statement/criticism (as italicised and underlined in paragraph 29 above and as elaborated further in paragraphs 5-6 of the PT 2^nd Report in paragraph 30 above after having considered the CHB Report) was due to differences between his views and those of Dr CHB because as a specialist in paediatric surgery he treated the symptom of abdominal distension as a serious clinical feature whereas Dr CHB as a specialist in paediatrics focused on the soft abdomen and presence of bowel sounds as reassuring clinical features. Chan said this again showed Prof PT wrongly applied the standard of a specialist in paediatric surgery.

40.  Chan disagreed that paragraphs 16-17 of the PT 2^nd Report (see paragraph 30 above) showed Prof PT based his comments on the standard of care expected of a reasonably competent paediatrician. Paragraph 16 of the PT 2^nd Report merely stated it should be within a paediatrician’s expertise to recognise pneumoperitoneum on AXR or CT scan, and paragraph 17 of the PT 2^nd Report merely stated P’s intellectual disabilities would not influence D1’s ability to arrange earlier abdominal x-ray, ultrasound examination or surgical consultation. Chan contended these paragraphs could not displace the message/implication in paragraph 8 of the PT 2^nd Report that, in considering the issue of earlier investigations/referral, Prof PT used the perspective of a specialist in paediatric surgery.

41.  Chan also noted with interest that PSols’ letter of instructions to Prof PT required him to comment on whether D1 fell below “the requisite standard of care” without informing him the requisite standard was that of a specialist in paediatrics and not that of a paediatric surgeon.

42.  Answer (2) of the PT 1^st Letter mentioned the current President of The Hong Kong Paediatric Society was a paediatric surgeon, but Chan noted such society was not an academic or regulatory body, and its website stated (a) “[the] Society was never meant to be an academic or regulatory body ……”, (b) the function of such society was “to organize scientific and social meetings in order to encourage the interchange of ideas and to stimulate cooperation in the various fields of Paediatrics”, and (c) membership of such society included doctors and non-doctors. Chan did not think the fact the president of such society was a specialist in paediatric surgery could displace the long established Bolam principle. Chan further noted the current president, vice president, honorary secretary, honorary treasurer, ex-officio member and members of The Hong Kong College of Paediatricians being one of HKAM’s constituent colleges were all specialists in paediatrics, and the only exception was the immediate past president who was both a fellow of the HKAM (Paediatrics) and a specialist in Paediatric Immunology.

43.  Chan noted PSols obtained further clarifications from Prof PT in the form of the PT 2^nd Letter dated 20 November 2019, and suggested such letter raised more problems than answers:

(a)

In Answer (2) in the PT 2nd Letter, Prof PT purported to give expert opinion on the training of a paediatrician and observed that a paediatrician was expected to make appropriate referrals for serious conditions requiring treatment outside his/her capabilities, but Prof PT had never been a paediatrician and did not receive full paediatrician’s training. Chan queried how Prof PT would be able to comment on what was within or not within a paediatrician’s capabilities. Chan believed the PT 2nd Letter failed to displace the problematic remarks in the PT 2nd Report, which unequivocally showed Prof PT gave expert opinion from the perspective of a specialist in paediatric surgery (at least on the referral issue), which in turn would create problems for the parties and the court should Prof PT be called to give expert evidence on the issue of liability at trial (eg, the Court would not be able to resolve difference in expert opinion on the same medical issue given by experts from 2 different specialties, especially if the 2 experts had entirely different approaches to medical issues due to the difference between their specialties).

(b)

In Answer (8) of the PT 2nd Letter, Prof PT argued that a specialist in paediatric surgery actually had more experience than a specialist in paediatrics in the entire spectrum of early to late diagnosis and its consequences, but Chan contended this, once again, highlighted the unfairness and danger of Prof PT criticising D1’s management based on the standard or the “higher” standard of a specialist in paediatric surgery.

44.  Ds’ stance was that Prof PT should not have adopted a different standard (ie the standard of a specialist in paediatric surgery) to criticise the management of D1 who was a specialist in paediatrics. Given the issues mentioned above and the danger/unfairness of Prof PT adopting a different (or “higher”) standard of care when criticising D1, Ds took the view that, in the interests of justice and fairness, the PT 1^st/2^nd Reports should be withdrawn from the present action. Ds would not object to P instructing a new expert in the field of paediatrics (ie a specialist in paediatrics) in place of Prof PT.

IX.  HUI AFF

45.  The Hui Aff acknowledged one of P’s principal allegations was that Ds failed to timely refer P to a proper specialist (such as a paediatric surgeon) despite persistent abdominal distension on 15 and 17 March 2014 as evident from (a) the particulars of negligence and/or breach of contract and the averment on causation pleaded in the SoC (see paragraphs 8 and 10 above), and (b) D1’s Referral Letter dated 18 March 2014 to the surgeon at QEH’s department of paediatrics on 18 March 2014 (see paragraph 4 above).

46.  Following D1Sols’ 3/6/19 Letter, PSols sought clarification from Prof PT who gave the PT 1^st Letter (see paragraph 31 above). The Hui Aff placed emphasis on Answers (1)-(2) of the PT 1^st Letter (see italicised and underlined parts in paragraph 31 above), but noted despite clarification in the PT 1^st Letter that Prof PT provided opinion on the standard expected of a reasonable specialist in paediatrics, Ds filed the Summons to inter alia ask the parties to refrain from arranging the without prejudice meeting between Prof PT and Dr CBH pursuant to Master Roy Yu’s Order dated 29 January 2019 (see paragraph 19(b) above).

47.  Hui said the Chan 1^st Aff showed Ds did not dispute that the 2 specialties of paediatrics and paediatric surgery overlapped, and that Prof PT possessed relevant qualification in the field of paediatrics, but Chan alleged “having some relevant qualifications in paediatrics from the UK does not necessarily mean that [Prof PT] has the necessary expertise to comment on the management of a Specialist in Paediatric in Hong Kong” (see paragraph 38 above). Hui claimed it was inappropriate to undermine Prof PT’s qualifications, expertise and experience by saying he merely had “some relevant qualifications”. Apart from the numerous qualifications, publications and positions evident in Prof PT’s curriculum vitae, Prof PT stated in Answer (3) of the PT 1^st Letter that he was an examiner of “MBChB Paediatrics (U of Liverpool), and Diploma of Child Health (UK)”, and that he interacted with paediatricians on a daily basis in his professional practice, which Hui said spoke for itself. Hui said it was difficult to envisage Prof PT could have been a university examiner of paediatrics without knowledge and experience in the field.

48.  In respect of the allegation in the Chan 1^st Aff that Prof PT “used the wrong standard”, Hui said the PT 1^st Report should be read as a whole and not out of context (as Ds appeared to have done). He particularly referred to the references to what “competent doctor”, “physician” and/or “primary physician” should have done and when “it would be reasonable to expect a referral for a second opinion or more investigations” in paragraphs 21, 23 and 29 of the PT 1^st Report (see italicised and underlined parts in paragraph 29 above).

49.  Similarly, Hui claimed careful reading of the PT 2^nd Report in its full context would show Prof PT was in fact commenting on the standard of care expected of a reasonably competent paediatrician, especially the references to “a paediatrician’s clinical expertise” in paragraph 16 and to “the paediatrician’s ability to arrange an earlier abdominal XR” and the argument that “the Paediatrician should have heightened awareness of disease progression and complication …… and have more urgency in arranging the investigations and consultation” in paragraph 17 of the PT 2^nd Report (see italicised and underlined parts in paragraph 30 above).

50.  Hui said P on 5 November 2019 sought further clarification from Prof PT who by the PT 2^nd Letter dated 20 November 2019 confirmed in Answer (7) that “[the] requisite standard of care” under paragraph 23 of the PT 1^st Report referred to “the standard of care expected of a reasonably competent paediatrician inthe aspect of timely referral” (see paragraph 32 above).

51.  Hui said Answers (1)-(2) of the PT 2^nd Letter also responded to the Chan 1^st Aff that cited paragraphs 8-9 of the PT 2^nd Report in support of the suggestion that Prof PT applied the wrong test (see paragraph 32 above, especially the italicised and underlined parts). Hui suggested that had Ds requested P to seek clarifications in the form of questions similar to those set out in the PT 2^nd Letter, the Summons would have been wholly unnecessary.

52.  In response to the references in the Chan 1^st Aff to various medical organisations, P also sought guidance from Prof PT who gave Answer (6) of the PT 2^nd Letter that he did not see such references to have “any relevance whatsoever to [his] expertise and ability to comment on the standard of [D1] as a reasonably competent paediatrician” (see paragraph 32 above). It was said that in any event a copy of the specialty descriptions issued by the HKAM on 3 October 2019 described the respective discipline as follows:

“Hong Kong College of Paediatrics

18. Paediatrics

Paediatrics is a discipline of Medicine that deals with the promotion of health, normal growth and development, prevention and treatment of diseases, and management of psychological and learning issues in infants and children from the perinatal period to adolescence.

………

College of Surgeons of Hong Kong

……

58. Paediatric Surgery

Paediatric Surgery is a discipline of Surgery that deals with the diagnosis and treatment of surgical conditions of the young from the perinatal period to adolescence. It includes minimal access therapy as well as diagnostic and therapeutic endoscopies for patients in this age group.” (my emphasis)

53.  Hui said that in the present case, given the fact D1 ultimately referred P to a paediatric surgeon at QEH due to P’s surgical condition of gut perforation, expert opinion of a paediatric surgeon commenting on the diagnosis of surgical condition in accordance with the specialty description was clearly necessary, relevant and probative.

54.  On the matter of causation, Hui said that pursuant to various court orders and paragraph 66(5) of Practice Direction 18.1, expert evidence of a paediatric surgeon also served the purpose of dealing with issues of causation including but not limited to:

(a)	whether an earlier referral to a paediatric surgeon would have prevented P from suffering the injuries and/or disabilities he ultimately suffered;
(b)	whether an earlier surgical intervention would have reduced the extent of the surgeries required thereby reducing the injuries arising therefrom;
(c)	whether an earlier surgical intervention would have provided P an opportunity of gaining recovery and/or restoration to his pre-incident condition;
(d)	to what extent D1’s delay in referral to a paediatric surgeon caused the injuries and/or disabilities P ultimately suffered.

55.  Prof PT dealt with the issues of causation in paragraph 30 of the PT 1^st Report (see the italicised and underlined parts in paragraph 29 above), identified the “clinical window” of opportunity in paragraph 14 of the PT 2^nd Report (see the italicised and underlined parts in paragraph 30 above), and for the avoidance of doubt, Answer (8) in the PT 2^nd Letter further clarified Prof PT’s expertise in providing opinion on causation (see the italicised and underlined parts in paragraph 32 above). So Hui claimed that quite irrespective of the complaint that Prof PT as a paediatric surgeon applied the wrong test in commenting on the standard of care (which Hui denied), Prof PT had the expertise to deal with issues of causation arising from delay in proper diagnosis that would lead to timely referral.

56.  Hui therefore asked the court to refuse Ds’ application to revoke the order of Master Roy Yu dated 28 August 2018 (see paragraph 19 above) that was made by consent, and to permit P to rely on liability expert evidence of Prof PT in view of the procedural history of the present action, Prof PT’s expertise as a paediatric surgeon, and the necessity of expert evidence on causation arising from delayed diagnosis/ referral.

X. APPROACH TO THE APPEAL

57.  Extensive efforts were spent by the parties in the affidavits/affirmation filed in relation to the Summons and in counsel’s written submissions to canvass (a) the procedural history in relation to the expert directions granted in the course of case management of the present action, and (b) the nature of the Appeal (with references to parties’ correspondence and court documents). In particular, P claimed Ds by the Summons/Appeal were trying to revoke the order of Master Roy Yu dated 28 August 2018 that was made by consent (see paragraph 19 above), and Ds should not be allowed to do so when (i) they all along knew and had not objected to P’s engagement of a paediatric surgeon as his expert witness on liability (or on liability and causation) (see paragraphs 12-13 above), (ii) impliedly represented they would not take out any interlocutory application to challenge Prof PT’s expertise (see paragraphs 15 and 18 above), and (iii) the court had made 3 orders with expert directions on 12 June and 28 August 2018 and 29 January 2019 (see paragraphs 13, 16 and 19 above) without reservation of Ds’ right to object.[3] Ds agreed that they first raised objection in the 3/6/19 Letter, but explained that the problem only became apparent upon disclosure of the PT 2^nd Report in late April 2019, especially in light of paragraph 8 of such report (see paragraph 30 above).

58.  There was no dispute the Appeal was in principle a de novo hearing of the Summons pursuant to Order 58 rule 1 of the Rules of the High Court (“RHC”),[4] but issue arose as to whether the Master Order was a case management decision on expert directions in which the court would not lightly interfere,[5] or whether there were good reasons for the appellate court to interfere as explained by Bharwaney J in Ng Wing Man, a mentally incapacitated person by his wife and next friend, Ho Siu Fun v Everbest Port Services Limited.[6]

59.  Further, whilst there was also no dispute that Order 38 rule 44 of the RHC provides that “[any] direction given under this Part of this Order may on sufficient cause being shown be revoked or varied by a subsequent direction given at or before the trial of the cause or matter”, issue arose as to whether there was “sufficient cause” (which is usually fact- and case-sensitive) to revoke or vary previous expert directions,[7] eg expert directions referred to in Part IV above.

60.  But happily, through useful discussion between the bar and the bench at the Hearing, a number of matters were agreed:

(a)	Prof PT was specialist in paediatric surgery, and D1 and Dr CHB were specialists in paediatrics;
(b)	the relevant standard to be applied under the Bolam test on the issue of liability for medical negligence in the present action was whether D1 had acted in accordance with the practice accepted as proper by a responsible body of “medical men skilled in that particular art”, which particular art was that of paediatric specialists and not that of paediatric surgery specialists;
(c)	a key issue raised by the Summons was (i) whether Prof PT had the requisite expertise to give expert evidence on the standard of care in (b) above (“Expertise Issue”), and/or (ii) whether he had applied such standard of care in the PT 1st/2nd Reports as further clarified in the PT 1st/2nd Letters (“Standard Issue”) (bearing in mind that an expert is required to reduce his opinion in writing – see Order 38 rule 37(1) of the RHC);
(d)	another issue raised by the Summons was whether Prof PT as a specialist in paediatric surgery had the appropriate expertise to give expert opinion on the issue of causation (“Causation Issue”);
(e)	given that the Summons/Appeal raised the issue of admissibility of Prof PT’s expert opinion in the PT 1st/2nd Reports, and that the Expertise, Standard and Causation Issues went to the core or fundamental basis of Prof PT’s opinion in such reports, Mr Tsoi and Mr Lam SC agreed that, in light of Order 38 rule 44 of the RHC, it was open to this court to consider afresh the expert directions granted for P to adduce expert evidence from Prof PT on the issues of liability and/or causation without having to revisit the reasons for decision by Master Roy Yu in granting the Master Order.

XI.  LEGAL PRINCIPLES

(a)  Medical negligence – standard of care

61.  The relevant legal principles are not disputed and can be stated shortly. D1 owed P a duty to exercise reasonable care and skill. If he failed to show such care and skill, he would be negligent and would be liable for any loss caused as a result of his negligence. P contended that D2 was vicariously liable for D1’s acts and omissions.

62.  According to Jackson & Powell on Professional Liability, “[a] practitioner who specializes in any particular area of medicine must be judged by the standard of skill and care of that specialty”.[8] A medical practitioner who acts in accordance with a practice accepted as proper by a responsible body of medical opinion will not be found to have failed to exercise reasonable care and skill and will not be negligent. The proper approach is set out by McNair J in Bolam v Friern Hospital Management Committee as follows:[9]

“…… The test is the standard of the ordinary skilled man exercising and professing to have that special skill. A man need not possess the highest expert skill; it is well established law that it is sufficient if he exercises the ordinary skill of an ordinary competent man exercising that particular art. ……” (my emphasis)

“…… that he is not guilty of negligence if he has acted in accordance with a practice accepted as proper by a responsible body of medical men skilled in that particular art …… Putting it the other way round, a man is not negligent, if he is acting in accordance with such a practice, merely because there is a body of opinion who would take a contrary view. At the same time, that does not mean that a medical man can obstinately and pig-headly carry on with the same old technique if it has been proved to be contrary to what is really substantially the whole of informed medical opinion ……” (my emphasis)

63.  This was echoed by Lord Scarman in Maynard v West Midland Regional Health Authority who said as follows:[10]

“I would only add that a doctor who professes to exercise a special skill must exercise the ordinary skill of his specialty. Differences of opinion and practice exist, and will always exist, in the medical as in other professions. There is seldom one answer exclusive of all others to problems of professional judgment. A court may prefer one body of opinion to the other: but that is no basis for a conclusion of negligence.” (my emphasis)

Thus, in considering whether there was breach of duty, ie whether in the present case D1 was negligent in that he failed to act with reasonable care and skill in the treatment of P, the requisite standard of care would be that of the ordinary skilled person practising the medical skills in question, ie “that particular art” or “his specialty”, which in the present case was paediatric specialty.

64.  In the course of time, there have been some inroads to the above principles.[11] First, where there are 2 bodies of responsible professional opinion, and a medical practitioner acts in accordance with one of the bodies of professional opinion, he will not be negligent simply because there is another body of professional opinion that would have pursued a different course of action, but if a practitioner acts in accordance with a body of professional opinion which is not capable of withstanding logical analysis, then the person is not acting in accordance with a body of “responsible” professional opinion, and may be liable in negligence. This has been explained by Lord Browne-Wilkinson in Bolitho v City and Hackney Health Authority.[12]

65.  DHCJ To in Zhuang PP Holdings Limited formerly known as China United Holdings Limited & ors v Lam How Mun Peter & ors explained the other 2 inroads as follows:[13]

“27. Secondly, in Nye Saunders & Partners,[14] Stephen Brown LJ held that where the evidence of the expert amounted to no more than an expression of his personal opinion as to what he would or would not have done in the circumstances, the judge was entitled to take the view that such evidence falls short of constituting evidence of a responsible body of architects: see also Midland Bank Trust Co Ltd and another v Hett, Stubbs & Kemp (a firm) [1978] 3 WLR 167. In effect, in such a case, the initial criteria for the application of the Bolam test are not met.

28.  Thirdly, in Gold v Haringey Health Authority [1988] QB 481 at 490, Lloyd LJ held that if the giving of advice required no special skill, then the Bolam test should not apply. In order words, where it is not necessary to apply any particular expertise to decide whether the defendant has failed to exercise the skill and care expected of an ordinary member of the surveying profession, there is no room for application of the test.”

66.  Further, a professional person is not to be judged by the wisdom of hindsight, so the breach of duty should only be judged prospectively based upon what was known or ought to have been known.

(b)  Determining admissibility of expert evidence

67.  It was made clear in the pre-CJR authority of Wong Hoi Fung v American International Assurance Co (Bermuda) Ltd & anor that the court has an inherent power to rule on the admissibility of expert evidence at a pre-trial stage:[15]

“11. Modern judicial authorities recognise that the court has inherent power to rule on the admissibility of expert evidence at a pre-trial stage …… Where the proposed expert evidence is plainly inadmissible or irrelevant, the court ought to exercise its discretion to refuse the admission of such evidence. But where the court cannot form a clear view on the relevance of the proposed expert evidence or where it considers that the proposed evidence is clearly relevant, then it should grant leave for the evidence to be adduced at the trial ……

12. In deciding whether certain proposed expert evidence should be received, the relevant test has been stated to be a two-stage one. Firstly, the evidence has to be admissible as ‘expert evidence’ for the purpose of s.58 of the Evidence Ordinance (Cap.8). Secondly, the evidence must be relevant, in the sense that it is helpful to the court in arriving at its decision on one or more of the issues to be resolved: Barings Plc (in liquidation) & Another v Coopers and Lybrand & Others (unrep., 9 February 2001), Evans-Lombe J at paras.44-45.” (my emphasis)

68.  The Court of Appeal in Shenzhen Futaihong Precision Industry Co Ltd & ors v BYD Co Ltd & ors[16] pointed out that paragraph 596 of the Final Report on CJR identified the following as conditions for admissibility of expert evidence (page 180):

(a)	the subject matter of the opinion must fall within an area in which expert evidence may properly be given;[17]
(b)	the witness must be qualified as an expert to give the evidence of the type in question;
(c)	his evidence must be relevant to the issues being litigated.[18]

69.  But the Court of Appeal emphasised that the giving of expert directions is a matter of case management, and pointed out that after the implementation of the CJR, the courts “can also take in account of the probative value of an expert report in exercising case management power ……” (page 180):

“11. Counsel drew our attention to the observation of Butler-Sloss LJ in Re M and R (minors) [1996] 4 All ER 239 at p 254 to suggest that if the expert evidence is arguably relevant but ultimately unhelpful the court should still admit the same whilst indicating at the same time that the evidence would carry little weight. That observation was made in a case concerning children where there were allegations of sexual abuse. The judge hearing the application had evidence (without any objection as to admissibility) from two child psychiatrists that sexual abuse had probably occurred. The judge found otherwise. In the appeal the discussion on admission of expert evidence focused on the abandonment of the ultimate issue rule by virtue of s 3 of the Civil Evidence Act 1972. It was in such context that Her Ladyship made the observations cited by counsel.

12. With respect, we do not regard those observations as militating against the duty of a judge in exercising the case management function when giving expert directions as discussed above. In other words, the court will not give directions for expert evidence to be adduced (carrying with it the incidence of substantial costs being incurred on its preparation and court time spent on the same) simply on the basis that the court cannot rule out a possibility of such evidence being relevant and helpful in the sense as discussed above. If the applicant for expert directions fails to persuade the court on relevance and necessity of such evidence, the application should be dismissed.” (my emphasis) (pages 182-183)

“40. We cannot find any fault in this analysis by the Judge. In any event, in the absence of concrete evidence from the BYD Parties demonstrating the relevance and necessity of expert evidence to resolve the pleaded issues on those paragraphs, the Judge was entitled to refuse to direct that expert evidence on (ii) to be obtained which would only lead to proliferation of unhelpful expert issues that could lengthen the trial and increase the costs of the litigation.” (my emphasis) (page 192)

70.  In SUNeVision Holdings Ltd v Hong Kong Science and Technology Parks Corporation (Global Switch Hong Kong Limited, interested party),[19] the plaintiff in that case referred to Wong Hoi Fung and submitted that if the court is in doubt as to the relevance of proposed expert evidence, it should grant leave for it to be adduced at the trial. But G Lam J held that insofar as this submission was at variance with the approach recommended by the Court of Appeal in Shenzhen Futaihong Precision Industry Co Ltd set out in the above paragraph, it was the latter that he should (and in my view, as this court should) follow (paragraph 15). The learned judge at paragraph 16 added that “[monitoring] attempts to introduce expert evidence is not just a power of the court but its duty in exercising case management functions”.

71.  Lam VP also underlined such post-CJR approach in Taching Petroleum Company, Limited v Meyer Aluminium Limited as follows:[20]

“13. The proper approach for admission of expert evidence in the post-CJR era was discussed by the Court of Appeal in Shenzhen Futaihong Precision Industry Co Ltd v BYD Co Ltd [2018] HKCA 408 at [3] to [13]. The approach adopted by the Deputy President, based on the pre-CJR authority of Wong Hoi Fung v American International Assurance Co [2002] 3 HKLRD 507, was more relaxed towards admission of expert evidence. See in particular [12], [40], [51] of Shenzhen Futaihong Precision Industry Co Ltd v BYD Co Ltd, supra. At [12], the Court said,

‘…… In other words, the court will not give directions for expert evidence to be adduced (carrying with it the incidence of substantial costs being incurred on its preparation and court time spent on the same) simply on the basis that the court cannot rule out a possibility of such evidence being relevant and helpful in the sense as discussed above. If the applicant for expert directions fails to persuade the court on relevance and necessity of such evidence, the application should be dismissed.’”

In that case, the court below regarded relevance as the key consideration in the applications concerning expert evidence, and held that certain proposed expert evidence was outside the scope of or not relevant to the pleaded issues (paragraphs 14-18), and that it was not permissible use of expert evidence to fish for evidence to formulate a case (paragraph 19). On such basis, Lam VP agreed with such case management approach “[subject] to our observation above by reference to Shenzhen Futaihong Precision Industry Co Ltd v BYD Co Ltd” (paragraph 20).

72.  Mr Tsoi also referred me to Kennedy v Cordia (Services) LLP[21]where a home carer slipped and fell on an icy path during a home visit and claimed damages against her employer. Whilst this appeared to be an everyday accident, it raised question inter alia as to whether health and safety practice could properly be the subject of expert evidence. The answer was in the affirmative. It was said the evidence of the claimant’s expert on factual matters was admissible as it was necessary, it assisted the judge and the expert had the required qualifications and experience, and it provided a basis for the court to address the legal issues. The UK Supreme Court held at pages 611-614 as follows:

“44. …… There are in our view four considerations which govern the admissibility of skilled evidence: (i) whether the proposed skilled evidence will assist the court in its task; (ii) whether the witness has the necessary knowledge and experience; (iii) whether the witness is impartial in his or her presentation and assessment of the evidence; and (iv) whether there is a reliable body of knowledge or experience to underpin the expert’s evidence. All four considerations apply to opinion evidence, although, as we state below, when the first consideration is applied to opinion evidence the threshold is the necessity of such evidence ……

45. Assisting the court. It is for the court to decide whether expert evidence is needed, when the admissibility of that evidence is challenged. ……

……

48. An expert must explain the basis of his or her evidence when it is not personal observation or sensation; mere assertion of ‘bare ipse dixit’ carried little weight …… if anything, the suggestion that an unsubstantiated ipse dixit carried little weight is understated; in our view such evidence is worthless.

……

50. The witness’s knowledge and expertise. The skilled witness must demonstrate to the court that he or she has relevant knowledge and experience to give …… opinion evidence. Where the skilled witness establishes such knowledge and experience, he or she can draw on the general body of knowledge and understanding of the relevant expertise ……

……

54. Reliable body of knowledge or experience. What amounts to a reliable body of knowledge or experience depends on the subject matter of the proposed skilled evidence ……

55. In many cases where the subject matter of the proposed expert evidence is within a recognised scientific discipline, it will be easy for the court to be satisfied about the reliability of the relevant body of knowledge. There is more difficulty where the science or body of knowledge is not widely recognised. ……

56. We agree with that proposition, which is supported in Scotland and in other jurisdictions by the court’s refusal to accept the evidence of an expert whose methodology is not based on any established body of knowledge. ……”

73.  Although less robustly said than the guidance by the Court of Appeal in Shenzhen Futaihong Precision Industry Co Ltd as explained in Taching Petroleum Company, Limited, Kennedy also placed emphasis on the court’s case management powers for “policing the performance of an expert’s duties” (see below) and to encourage economy in litigation (pages 615-616), which in turn suggested that the court can rule on the admissibility of expert evidence at a pre-trial stage as a matter of case management:

“58.     It is not the normal practice of the Scottish courts to hold preliminary hearings or proofs on the admissibility of the evidence of skilled witnesses. Considerations of cost and practicability may often make such a course unattractive. Where the court has significant powers of case management, as in certain actions based on clinical negligence or relating to catastrophic injuries ……, a judge can address concerns about the evidence in respect of a skilled witness at a case management hearing and discuss with counsel how they are to be resolved. Wide opportunities for such case management in personal injury actions are likely to result from the implementation of Lord Gill’s “Scottish Civil Courts Review”. ……

……”

(c)  Assessing weight of expert evidence

74.  Mr Tsoi referred me to C (by his father and litigation friend F) v North Cumbria University Hospitals NHS Trust in which Green J set out the “principles and considerations apply to the assessment of …… expert evidence ……” in the case before him:[22]

“25. In the present case I have received evidence from four experts, two on each side. It seems to me that in the light of the case law the following principles and considerations apply to the assessment of such expert evidence in a case such as the present:

(i) Where a body of appropriate expert opinion considers that an act or omission alleged to be negligent is reasonable a court will attach substantial weight to that opinion.

(ii) This is so even if there is another body of appropriate opinion which condemns the same act or omission as negligent.

(iii) The court in making this assessment must not however delegate the task of deciding the issue to the expert. It is ultimately an issue that the court, taking account of that expert evidence, must decide for itself.

(iv) In making an assessment of whether to accept an expert’s opinion the court should take into account of a variety of factors including (but not limited to): whether the evidence is tendered in good faith; whether the expert is ‘responsible’, ‘competent’ and/or ‘respectable’; and whether the opinion is reasonable and logical.

(v) Good faith ……

(vi) Responsible/competent/respectable. In Bolitho Lord Brown Wilkinson cited each of these three adjectives as relevant to the exercise of assessment of an expert opinion. The judge appeared to treat these as relevant to whether the opinion was ‘logical’. It seems to be that whilst they may be relevant to whether an opinion is ‘logical’ they may not be determinative of that issue. A highly responsible and competent expert of the highest degree of respectability may, nonetheless, proffer a conclusion that a court does not accept, ultimately, as ‘logical’. …… ‘Competence’ is a matter that flows from qualification and experience. In the context of allegations of clinical negligence in an NHS setting particular weight may be accorded to an expert with a lengthy experience in the NHS. …… This does not mean to say that an expert with a lesser level of NHS experience necessarily lacks the same degree of competence; but I do accept that lengthy experience within the NHS is a matter of significance. By the same token an expert who retired 10 years ago and whose retirement is spent expressing expert opinions may turn out to be far removed from the fray and much more likely to form an opinion divorced from the current practical reality. ‘Respectability’ is also a matter to be taken into account. Its absence might be a rare occurrence, but many judges and litigators have come across so called experts who can ‘talk the talk’ but who veer towards the eccentric or unacceptable end of the spectrum. Regrettably there are, in many fields of law, individuals who profess expertise but who, on true analysis, must be categorized as ‘fringe’. A ‘responsible’ expert is one who does not adapt an extreme position, who will make the necessary concessions and who adheres to the spirit as well as the words of his professional declaration (see CPR35 and the PD and Protocol).

(vii) Logic/reasonableness: By far and away the most important consideration is the logic of the expert opinion tendered. A judge should not simply accept an expert opinion; it should be tested both against other evidence tendered during the course of a trial, and, against its internal consistency …… There are two other points which arise in this case which I would mention. First, a matter of some importance is whether the expert opinion reflects the evidence that has emerged in the course of the trial. …… Secondly, a further issue arising in the present case emerges from the trenchant criticisms …… made of the defendant’s two experts due to the incomplete and sometimes inaccurate nature of the summaries of the relevant facts (and in particular the Clinical Notes) that were contained within their reports. …… Having said this, the task of the court is to see beyond stylistic blemishes and to concentrate upon the pith and substance of the expert opinion and to then evaluate its content against the evidence as a whole and thereby to assess its logic. If on analysis of the report as a whole the opinion conveyed is from a person of real experience, exhibiting competence and respectability, and it is consistent with the surrounding evidence, and of course internally logical, this is opinion which a judge should attach considerable weight to.” (my emphasis)

75.  In Sandra Battersby v Allan,[23] the defendant neurosurgeon performed a left fronto-temporal craniectomy (ie brain tumour surgery) on the plaintiff, who alleged that the defendant negligently caused damage to her left middle cerebral artery in the course of that surgery (paragraph 10), which led her to develop a right hemiplegia with consequent significant disabilities (paragraph 12). The allegation of negligence was denied by the defendant. The plaintiff had initial difficulty in securing an expert report by a neurosurgeon, so she served an expert report by a neurologist, but she later also served an expert report by a neurosurgeon (paragraphs 14 and 19).

76.  The letter of instructions sent to the consultant neurologist sought his expert opinion on inter alia the following question: “[did the defendant] exercise the care and skill one would expect from a neurosurgeon of his professional experience in performing the surgery and in particular does the thermal injury to the cerebral artery represent a departure from an acceptable level of care?” (paragraph 16). The consultant neurologist gave his opinion in his report, and stated that “[the] opinion above is that of a neurologist” and that “a neurosurgical opinion evaluating the above might be obtained” (paragraph 17). The consultant neurologist explained that the opinion given in his report was based on his training in neurology, his consultancy in neurology and his position as a fellow in neuropathy (paragraph 28), and that curriculum (which set out the training pathways for training in neurology and continuing professional development) made clear  the training and skill of a neurologist included training in neuroanatomy and neuropathology, including the study of brain tumours and associated surgery, and the learning objective under “neurosurgery and vascular surgery” included inter alia indications of common neurosurgical and vascular surgery procedures (paragraphs 29-30). The court could not conclude the consultant neurologist followed the precise course of study set out in the curriculum, but was “satisfied …… he must necessarily have followed a similar course of study in order to be conferred with the Fellowship to which he referred to in his correspondence” (paragraph 32).

77.  The defendant objected on the basis that the consultant neurologist lacked the necessary expertise to express at least some of the opinions in his report (paragraphs 18 and 33-37), but the plaintiff contended that the evidence established the consultant neurologist had the requisite specialised knowledge to allow him to express the opinions in his report as evident from his clarification report and the curriculum referred to above. Bellow J of the New South Wales Supreme Court held that the opinion by the consultant neurologist being one of specialised knowledge based on his training, study and experience was admissible:

“41. Whether formal qualifications will be sufficient to demonstrate the necessary expertise in relation to particular applications of such qualifications is necessarily a matter which must be determined according to the facts of the particular case. That issue has been considered in the context of expert evidence from medical practitioners.

……

43. …… in R v Farquharson (2009) 26 VR 410; [2009] VSCA 307 …… the Court considered whether an opinion expressed by a specialist thoracic physician was admissible to prove that a person was not likely to have suffered a cough syncope before driving a car off a road and into a dam. The Court (Warren CJ, Nettle JA (as his Honour then was) and Redlich JA) said at [79] (citations omitted):

79. … [T]here must be an identified aspect of that field of specialised knowledge in which the witness demonstrates that, by reason of specific training, study or experience, the witness has become an expert. The nature and extent of studies required, however, depend on the science in question. It is important to keep in mind that it is not the general nature, but also the precise character of the question upon which expert evidence is sought to be given which is determinative of whether the putative expert’s qualifications are sufficient. Satisfaction of the second test is thus a question of fact and degree. ……

44. Neither party in the present case adduced any specific evidence as to the extent of the differences in the specialties of a Neurologist on the one hand, and a Neurosurgeon on the other. However, the definitions of those terms are informative.

……

47. It will be apparent from these definitions that although the two specialties are different, they have a number of common features. Both are centred on diseases of the nervous system and the brain. Both necessarily require knowledge of the anatomy and physiology of the brain. Both stem from common areas of training, study and experience in diseases of the nervous system and the brain. The principal difference between the two is that a Neurologist is primarily concerned with the treatment and management of such diseases, whilst a Neurosurgeon is primarily concerned with the conduct of surgical procedures in relation to them. However as I have pointed out, fundamental to both specialties is expertise in the anatomy, physiology and pathology of the nervous system, including the brain.

48. …… The opinion expressed by [the consultant neurologist] in the present case is clearly based upon his knowledge of, and his training, study and experience in, those matters. It is also evidence that [the consultant neurologist’s] opinions are based, at least in part, upon matters of physiology, an area in which he has considerable training, study and experience.

49. I am mindful of the observations of the Court in Farquharson (at [79]) regarding the importance of considering the precise character of the question upon which the expert evidence is sought to be given. In the present case, the precise character of the question is centred upon a surgical procedure to an area of the anatomy in which he has considerable training, study and experience. It may be the case that ultimately, the weight to be attached to [the consultant neurologist’s] opinion is less than that to be attributed to the opinion of a Neurosurgeon. However, questions of admissibility must not be confused with questions of weight: Farquharson at [81].

……”

78.  In my view, Sandra Battersby, an authority which Mr Tsoi strongly relied, helpfully pointed out that the admissibility of expert opinion in each case turns on its own context, and the expertise of the expert in question does not necessarily turn on whether his/her specialty and/or qualifications were related to or fit precisely that of the defendant, but turns on whether his expertise (ie his/her specialty, knowledge, training, study and experience) is relevant to “the precise character of the question which expert evidence is sought to be given”.

79.  In Mr Dennis Lee v Colchester Hospital University NHS Foundation Trust,[24] the trial was due to start in 2 weeks, and the defendant applied to replace one of its experts who was a “specialist” consultant radiologist (who was dismissed from his NHS employment) with a “mere” consultant radiologist (paragraph 6). Robinson J held that whether to grant permission to put in additional or alternative evidence was a case management decision, and the applicant must adduce the reason for changing expert (paragraph 17). The learned judge was satisfied there was a genuine reason for seeking to change expert because “to refuse this application would compel the defendant to call an expert over whom there is a clear question mark” (paragraphs 18-19). Hence, the defendant was permitted to rely on the report of the “mere” consultant radiologist in substitution for the “specialist” consultant radiologist.

80.  In that case, the claimant was concerned that (a) his “specialist” consultant neuroradiologist was overqualified, having regard to the fact that the alleged breach of duty occurred at a District General Hospital and the responsible clinician was a consultant radiologist in practice at a District General Hospital, and (b) the consultant radiologist to be appointed by the defendant who was employed at a District General Hospital might be said to have more relevant experience (paragraph 20). But Robinson J said as follows:

“21. In the circumstances of this case I think that the claimant’s lawyers are being over-sensitive, I have no doubt whatsoever that a consultant neuroradiologist will be able to put himself into the position of radiologist in the position of the clinician whose acts or omissions are being called into question and give a view about acceptable and unacceptable practice within the well-known Bolam test, so I do not see that as an issue.”

However, Robinson J’s short judgment delivered shortly before trial focused on case management issues, and did not identify the “precise character of the question upon which the expert evidence is sought to be given” that would explain why a neuroradiologist would be able to give relevant opinion. Further, the concern raised did not go to the issue at hand being the suitability of the fresh expert, who was accepted to be of relevant specialty and experience, and it was just worry by the opposing party that if the defendant were to have a fresh expert of relevant expertise, his own expert might be over-qualified and hence arguably less relevant. Nevertheless, the plaintiff’s expert was still in the same specialty as the responsible clinician, ie he was a radiologist but had acquired “more relevant experience” that one who worked in a general hospital. I do not see Mr Dennis Lee to be in any way different from the guidance in Sandra Battersby.

XII.  EXPERTISE AND STANDARD ISSUES

(a)  Parties’ respective stance

81.  Mr Lam SC submitted the Expertise and Standard Issues raised the question of admissibility of the PT 1^st/2^nd Reports on the basis that (a) Prof PT was of a different expertise/specialty (ie a paediatric surgeon and not a paediatrician), and (b) more importantly, he applied the wrong threshold (ie that of a paediatric surgeon and not that of a paediatrician) in opining on acceptable and unacceptable practice within the Bolam test. On the other hand, Mr Tsoi relying on Sandra Battersby submitted that Ds’ complaints in relation to the Expertise and Standard Issues (which P disagreed on the basis that Prof PT had the relevant expertise and applied the correct standard) would only go to the weight of the opinion evidence to be assessed by the trial judge, but would not render the PT 1^st/2^nd Reports inadmissible because even though Prof PT was a paediatric surgeon he was able to view the position of D1 (whose acts or omissions were being called into question) from the perspective of a paediatrician and to express a view about acceptable and unacceptable practice of paediatricians within the umbrella of the Bolam test.

(b)  Expertise Issue

82.  The Expertise Issue raised the question whether Prof PT had the relevant expertise to opine on the expert issue before the court. Ds did not challenge Prof PT’s expertise as a specialist in paediatric surgery. The question was whether it was appropriate and admissible (ie relevant, necessary and of probative value) for him to give expert opinion on the standard of care applicable to D1 (ie specialist in paediatrics). It was for the court and not for Prof PT to determine the propriety for him to give such opinion, but what Prof PT said would be taken into consideration.

83.  Mr Tsoi submitted that the question of admissibility of Prof PT’s opinion in the PT 1^st/2^nd Reports was not a simple matter of ascertaining whether the specialty of paediatric surgery fit precisely into D1’s specialty in paediatrics. I agree given the discussion in Part XI(b) above and the principles enunciated in Sandra Battersby in paragraphs 77-78 above. In my view, it is necessary to start with Prof PT’s expertise and then identify the “precise character of the question” on which he gave opinion in the PT 1^st/2^nd Reports.

84.  Before I turn to such matters, it is perhaps useful to first deal with a proposition put forward by Mr Tsoi in his submissions, ie the specialty of paediatric surgery is a relevant and respectable body of opinion. Mr Tsoi submitted the law recognises there may be differences of opinion and practice in medical/other professions (see observations by Lord Scarman in Maynard in paragraph 63 above) and there may be various responsible bodies of medical opinion (see observations by McNair J in Bolam in paragraph 62 above), so even though paediatric surgeons would not fit precisely into D1’s qualifications, still the opinion of paediatric surgeons as a responsible body of opinion would be relevant if the correct standard (ie that of a reasonably competent paediatrician) was applied.

85.  In my view, the above submissions reflect a misunderstanding of the Bolam test. Putting aside for the moment the inroads as explained in Part IX(a) above, the Bolam standard of reasonable care and skill is established by reference to the general practice of the relevant specialty of the responsible clinician, who is not guilty of negligence if he has acted in accordance with a practice accepted as proper by “a responsible body of medical men” “skilled in that particular art”. So if the responsible clinician is a paediatrician, whether his acts/omissions are acceptable or unacceptable will be assessed against responsible body(ies) of medical opinion in “that particular art”, ie the specialty of paediatrics. It is correct to say that if there are several responsible bodies of opinion in the “particular art” of paediatrics (ie a responsible body of paediatricians adopts one practice but another responsible body of paediatricians adopts another practice), compliance with the practice of one such responsible body of paediatricians and non-compliance with the practice of another such responsible body of paediatricians is no basis for conclusion of negligence. The fact there are responsible body(ies) of medical opinion in other arts, eg paediatric surgery, is not relevant, and indeed, this was common ground between P and Ds in the present case (see paragraph 60(b) above).

86.  The true question was whether Prof PT as a paediatric surgeon had the requisite expertise to give relevant and admissible opinion evidence for establishing in the present action the practice of a responsible body of medical men “skilled in that particular art”, ie that of paediatrics and not paediatric surgery. This had to be considered on the basis of Prof PT’s specialty, training, knowledge, study and experience when viewed particularly against the issues being litigated, ie the “precise character of the question” on which Prof PT gave his opinion in the PT 1^st/2^nd Reports.

87.  As explained in paragraph 60(a) above, D1[25] and Dr CHB[26] were paediatricians, but Prof PT was a paediatric surgeon.[27] The PT 1^st Letter made the sage observation that “[illnesses] do not recognize specialties, humans do”. But in clinical negligence litigation, the court is concerned with human liability for negligent acts/omissions in the medical context. D1 was sued as a paediatrician, and his acts and omissions (if any) must be measured against the standard of skill and care of a reasonably competent specialist in paediatrics.

88.  In my view, there was no doubt “paediatrics” and “paediatric surgery” were recognised by the medical profession in Hong Kong to be 2 distinct/separate specialties: (a) they were registered under different specialist registers of the MCHK (see paragraph 34 above), (b) “paediatrics” (ie The Hong Kong College of Paediatricians) was 1 of 15 constituent colleges of the HKAM whereas “paediatric surgery” was one of the specialty boards of The College of Surgeons (see paragraph 34 above), and (c) the specialty descriptions issued by the HKAM gave different descriptions for the disciplines of “paediatrics” and “paediatric surgery” (see paragraph 52 above). Although the PT 1^st Letter and the Chan 1^st Aff accepted “paediatrics” and “paediatric surgery” were closely related in that both concerned infants and children, and that there were overlaps and synergies between these 2 specialties (see paragraphs 31 and 38 above), Prof PT confirmed there were still “differences” between the 2 specialties, and he recognised “paediatrics” was a medical specialty and “paediatric surgery” was a surgical specialty (see Answer (1) in the PT 1^st Letter in paragraph 31 above).

89.  Prof PT agreed that whilst “[both] share common knowledge of physiology and pathologies of infants and children”, “the foci and depths may differ” (see sections (1)-(2) in the PT 1^st Letter in paragraph 31 above). Mr Tsoi suggested the different “foci and depths” between the specialties of “paediatrics” and “paediatric surgery” went to the question of weight, but I do not agree. In my view, the different “foci and depths” went to the fact “paediatrics” and “paediatric surgery” were 2 distinct specialties. Of course, both paediatricians and paediatric surgeons would study, receive training and acquire skills on the anatomy, physiology and pathology of children, and on their growth and development from infancy to adolescence. But notwithstanding overlaps and synergies, it was the different “foci and depths” that caused paediatricians to be primarily concerned with child health and development, the prevention, management and treatment of diseases, and the management of physical, psychological, learning issues of children, and caused paediatric surgeons to be primarily concerned with the diagnosis of surgical conditions and the conduct of surgical procedures for children. Further, Prof PT’s observations in Answer (4) of the PT 2^nd Letter that the training of a paediatric surgeon covered his/her professional relationship with other relevant specialties including paediatrics, and a reasonable competent paediatric surgeon should know when to refer his/her patient to a paediatrician and vice versa, showed “paediatrics” and “paediatric surgery” were distinct specialties with cross-referrals between them (see paragraph 32 above). As Mr Lam SC submitted, the need for referral in appropriate cares implied that expertise in one specialty is lacking or insufficient in the other. “They play different roles, and co-operate with each other, in the overall treatment of  the patient.”

90.  On such basis, Mr Lam SC submitted (and I accept) the specialties of “paediatrics” and “paediatric surgery” were distinct/ separate, which distinction/difference was not a mere matter of label. One therefore had to consider whether such distinction/difference had any material bearing on the issues on which Prof PT was called upon to his opinion.

91.  Mr Lam SC submitted that generally speaking, in a professional negligence claim, expert evidence would be admitted only from a member of the specialty to which the defendant belongs, and expert evidence given by a witness from another specialty would be inadmissible. Mr Lam SC drew support from Jones, Medical Negligence which referred to the Bolam test with the proviso by Lord Diplock in Maynard (see paragraphs 62-63 above) and went on to say as follows:[28]

“…… The court must be satisfied that the experts’ view constitutes a ‘responsible’ body of professional opinion, experienced in the particular field of medicine concerned. Thus, on the question of liability it is important to obtain expert opinion in the appropriate specialty, and conversely the evidence of a specialist may be of little assistance in an action against a general practitioner. ……” (my emphasis)

92.  This was echoed by DHCJ To in Zhuang PP Holdings Limited formerly known as China United Holdings Limited & ors:

“32. As for the standard of care and skill required of a surveyor, it is that standard possessed by a person of ordinary competence exercising the same calling. …… Where a profession embraces a range of views as to what an acceptable standard of conduct, the competence of the surveyor is to be judged by the lowest standard that would be regarded as acceptable. But a court should be slow to find a professionally qualified man guilty of a breach of his duty of skill and care towards a client without evidence from those within the same profession as to the standard expected on the facts of the case and the failure of the professionally qualified man to measure up to that standard: Sansom & Another v Metcalfe Hambleton & Co [1998] PNLR 542 at 549, per Butler-Sloss LJ.”

93.  Mr Lam SC also referred to Jackson & Powell on Professional Liability which stated that in the context of medical negligence, the expert witness has 2 principal functions: (a) an explanatory or didactic function involving an explanation of the patient’s condition, treatment and its consequences, and (b) an assistance to the court in deciding whether the acts or omissions of the defendant constituted negligence.[29] In respect of (b) above, it was said as follows:

“So, amongst other matters, the expert will recount the current state of knowledge at the material time; give his view on what the general and approved practice was and/or what different schools of thought were relating to the patient’s condition; he will explain the risks attaching to particular courses of treatment and procedure; he may state what is the experience or skill usually displayed by medical practitioners with the relevant specialisation.” (my emphasis)[30]

“[The expert] will recount the current state of knowledge at the material time and the standards ordinarily observed in his profession, including any relevant general and approved practice or differing schools of thought. Expert evidence that a reasonably competent member of the defendant’s profession would not have committed the act or omission in question is generally necessary before the court will find that he was negligent. Thus in Sansom v Metcalfe Hambleton and Co Butler-Sloss LJ said[31]:

‘… a court would be slow to find a professionally qualified man guilty of a breach of his duty of skill and care towards a client (or third party) without evidence from those within the same profession as to the standard expected on the facts of the case and the failure of the professionally qualified man to measure up to that standard.’” (my emphasis)[32]

94.  To state the obvious, a cardiologist or ophthalmologist would not be an appropriate expert to give opinion on the acceptable or unacceptance practice of an orthopaedist even though they are all medical doctors. But the question would become a finer one if the 2 specialties were closely related as in the case of “paediatrics” and “paediatric surgery” both of which concern children notwithstanding differences between them that justified separate/distinct specialties (see paragraphs 88-89 above).

95.  The starting point is Sandra Battersby which requires the court to consider the expertise of expert in question against the precise issues on which such expert was asked to give opinion. Mr Lam SC submitted that such guidance was clearly illustrated by Sansom v Metcalfe Hambleton and Co.[33] In that case, before the plaintiffs purchased a property, they instructed the defendant to survey and report upon the structural condition. The plaintiffs alleged that the retaining wall at the property which they eventually purchased was defectively designed, and they sued the defendant (chartered surveyors) for alleged negligence in completing the survey report. Indeed, the experts who gave evidence for both parties accepted the retaining wall was not adequately designed and constructed, so the principal issue was whether there was anything in the condition of the property which ought to have indicated the retaining wall was inadequately designed and constructed. The plaintiffs relied on evidence led by an expert structural engineer rather than a chartered surveyor. It was held that “[although] there was no absolute rule that negligence by a chartered surveyor should be proved by expert evidence by chartered surveyor, there was no doubt that the general rule was that professional negligence should be proved by expert evidence given by a member of the appropriate profession. In the circumstances, the evidence led by the plaintiffs was inadequate to establish negligence by a surveyor appointed to carry out a report for a potential purchaser” (pages 88-89).

96.  Bulter-Sloss LJ (with whom Hutchison LJ and Sir John Vinelott agreed) noted at page 90 that the plaintiffs claimed the defendant chartered surveyors did not draw attention to the existence of a crack in the wing wall, did not consider its significance, and did not advise further investigation which, had it been pursued, would (it was said) have led to the conclusion that the retaining wall itself was inadequate for its task and needed to be replaced. Amongst the issues before the judge was inter alia the question whether the defendant chartered surveyors, if they had seen the crack, should have regarded it as potentially significant and in particular, whether they were negligent in not advising that advice should be sought from a structural engineer. The judge found inter alia that (a) the crack in the return wall was likely to have been caused in part at least, by failure of the retaining wall, and in this regard he preferred the evidence of the plaintiffs’ expert structural engineer to the defendant’s expert chartered surveyor wherever they were in conflict, and (b) the defendant’s chartered surveyors were “negligent in not noticing the crack and in not calling a structural engineer. In reaching the latter conclusion the judge rejected the evidence of the defendant’s expert …… chartered surveyor …… preferring that of [the plaintiff’s expert] …… structural engineer”.

97.  The plaintiff’s expert structural engineer gave evidence that he did not carry out structural surveys in the same way as chartered surveyors would carry out such surveys, and agreed that structural engineers were called in when there were structural problems to prepare structural engineer’s reports, but claimed that “I know things that surveyors on a day to day basis refer to me, and therefore I felt able to say that this cracking should have been pointed out” (page 91). The defendant’s counsel submitted this evidence demonstrated no more than there was a reasonable body of chartered surveyors who would have referred a similar crack to the plaintiff’s expert structural engineer for investigation, but such expert would have no knowledge whether similar cracks would not be referred to a structural engineer by other equally competent chartered surveyors (page 91).

98.  Butler-Sloss LJ stated that “[the] question whether a witness has the requisite expertise to give an opinion on any relevant matter is, in my judgment, one going to admissibility, not merely to weight” (page 93). After considering a number of authorities in which the courts had to consider the expertise of a witness engaged in the same field but with different qualifications,[34] including the Bolam test in relation to medical negligence cases where “the expert evidence would be expected to come from medical practitioners appropriately qualified to give it” (pages 93-94), Butler-Sloss LJ concluded as follows:

“In my judgment, it is clear, from both lines of authority to which I have referred, that a court should be slow to find a professionally qualified man guilty of a breach of his duty of skill and care towards a client (or third party) without evidence from those within the same profession as to the standard expected on the facts of the case and the failure of the professionally qualified man to measure up to that standard. It is not an absolute rule as Sachs LJ indicated by his example but, unless it is an obvious case, in the absence of the relevant expert evidence the claim will not be proved.

In the present appeal, I am satisfied that the judge did not have the evidence upon which he would have been able to make a finding of professional negligence against [the defendant chartered surveyors]. First, I do not consider that this was such an obvious case that there was not room for two views of the relevance of the crack and the steps, if any, which ought to have been taken in July 1992. Since it was not an open and shut case, such as that contemplated by Sachs LJ in the Worboys case, the evidence of [the plaintiff’s structural engineer] was not in my view expert evidence admissible in accordance with s 3 of the Civil Evidence Act 1972 on the issue of negligence. From the extract of his oral evidence, set out above, he was aware of the surveyors who did call him in to investigate. He, of course, did not know of those who did not call him in, nor whether it was reasonable or not reasonable not to do so. Consequently the judge did not have relevant and admissible evidence from the owners [ie the plaintiffs] to show failure by [the defendant chartered surveyors] to comply with the standard of skill and care to be exercised by a competent surveyor instructed by the owners. The judge failed to apply the correct test. If he had done so, he would have been driven to the conclusion that the owners had failed to prove their case. In my judgment the first ground of appeal is well founded and I would allow the appeal.” (my emphasis)

99.  In Sansom, the precise character of the question on which the expert structural engineer gave opinion was whether the defendant’s chartered surveyors, if they had seen the crack, should have regarded it as potentially significant and should have sought advice from a structural engineer (see paragraph 96 above). The relevant expertise called for by such “precise character of the question” was that of a chartered surveyor and not that of a structural engineer because even though the latter had day-to-day dealings with chartered surveyors from the receiving end, he could only be aware of the surveyors who called him in to investigate, but he would not know those who did not call him in nor whether it was reasonable or not reasonable not to do so (see paragraph 98 above). Thus, looking at the “precise character of the question” on which he gave opinion, the expert structural engineer did not have relevant and admissible evidence to give.

100.  Mr Tsoi noted the learned authors in the footnote to the dicta in Sansom cited in Jackson & Powell on Professional Liability (see paragraph 93 above) stated that “[however], it is not always essential that the expert witness practises in precisely the same discipline as the professional who is said to have breached his duty”,[35] and cited as example the case of Co-operative Group Limited v John Allen Associates Limited.[36] Before I turn to Co-operative Group Limited, I should point out in fairness that the dicta of Butler-Sloss LJ in Sansom did say: “It is not an absolute rule as Sachs LJ indicated by his example but, unless it is an obvious case, in the absence of the relevant expert evidence the claim will not be proved” (page 95 and paragraph 98 above). That must be right because relevance and admissibility do not turn on matching professional discipline between expert and clinician, but on matching the particular expertise of the expert to the “precise character of the question” on which he/she is to give opinion in the particular context of the case.

101.  In Co-operative Group Limited, a supermarket site was developed for the plaintiff by an independent developer. Given the difficult ground conditions the main contract provided for vibro- compacting ground improvement, and a performance specification for soil stabilisation by vibro-replacement techniques. The specification was prepared for the plaintiff by the defendant civil and structural engineers. In the course of preparing the specification, the defendant relied on specialist advice from a contractor (ie geotechnical and environmental consultants) who had expertise in vibro-replacement techniques and who had advised on the feasibility of those techniques for the subject development. Specialist subcontractors engaged by the main contractors were responsible for the design of the ground improvement scheme in accordance with the specification, but the main contractor and the defendant provided direct warranties to the plaintiff. After completion, the supermarket site was affected by differential settlement that caused sloping to the floors. The plaintiff sued the defendant for damages for breach of warranty, but the defendant contended that vibro-replacement had been a reasonable proposition, and even if it were not, there was no breach of duty to the plaintiff as the defendant relied on specialist advice.

102.  It was held that professionals by merely obtaining advice or design from another party do not divest themselves of their duties in respect of that advice, and they can only discharge their duty to exercise reasonable care and skill by relying on the advice of a specialist where the professional is considered by the court to have acted reasonably in doing so. In that case, the defendant had not failed to exercise reasonable care and skill because on the expert evidence before the court, it could not be said that vibro-replacement would never have worked on the site (paragraphs 237-240). But even if it were otherwise (which Ramsey J disagreed), question would have arisen as to whether the defendant was negligent in specifying vibro-replacement, and that would depend on whether the defendant acted reasonably in relying on the advice of the contractor (ie geotechnical and environmental consultants) and others (paragraph 241).

103.  The plaintiff supported their case with expert evidence from a geotechnical engineer on all engineering issues, but the defendant relied on expert evidence from a civil and structural engineer on civil and engineering issues, a geotechnical engineer on geotechnical and remediation issues, and an expert on ground treatment and improvement methods on vibro-replacement theory and techniques (paragraphs 110 and 136-139). Ramsey J referred to Sansom and the authorities cited therein, and declined to rule that the evidence of the plaintiff’s geotechnical engineering expert was irrelevant in the claim against civil and structural engineers, but found the defendant’s civil and structural engineering expert had the advantage of viewing matters from the perspective of practising in that capacity, and his evidence was preferred. In short, the learned judge held the difference in discipline did not preclude admissibility, and it went merely to analysis of the expert’s evidence and the weight to be attached to it (paragraphs 148-149).

104.  However, it was evident from the judgment that the plaintiff’s geotechnical engineering expert was not called upon to address any question of referral by structural and civil engineers to geotechnical engineers but on the professional responsibilities and actions of structural and civil engineers with particular emphasis on geotechnical matters (paragraph 148). The plaintiff’s geotechnical engineering expert frankly confessed he would not be able to give expert evidence on detailed structural matters (paragraph 147), but those matters were not “the precise character of the question” for such expert. It was in the context of “the professional practice of civil and structural engineers in relation to geotechnics and what might be expected of them in relation to their approach to geotechnical issues that arise on the project”, ie the actual handling of geotechnical matters, that the plaintiff’s geotechnical engineering expert was said to “[live and breath] the same air as structural engineers and civil engineers” (paragraphs 148-149) save for the caveat that he might be said to have more skill and experience on those issues as a leading geotechnical engineer (paragraph 149). In short, both structural and civil engineers and geotechnical engineers would have to face and deal with geotechnical issues on projects, and this was what gave rise to the professional responsibilities that were put in issue. Hence, the plaintiff’s geotechnical engineering expert could give admissible evidence in light of the “precise character of the question”, and the caution over his specialised technical skill went to the weight of his opinion. Ramsay J’s analysis and conclusion were consistent with the above authorities.

105.  In Hammersmith Hospitals NHS Trust & anor v Troup Bywaters & Anders,[37] the defendant consulting engineers were asked to advise the plaintiff on the replacement of the existing boilers at the hospital, and on the best way to dispose of clinical wastes which arose at the site. The defendant recommended the installation of waste incinerators which could also operate as boilers. The plaintiff wanted to be sure that the incinerators would dispose of the clinical wastes, generate sufficient heat and comply with environmental law. The defendant approached the manufacturers of the incinerators who assured them the specified requirements would be met, but did not carry out independent investigations (which might have revealed a report by the Department of Trade and Industry that the boilers did not perform adequately). The incinerators were installed and found to be inadequate. HH Judge Tomlinson QC rejected the plaintiff’s claim against defendant for professional negligence in relation to the advice given on the suitability of the incinerators and the failure to make further inquiries. It was held that the relevant standard of care was that of a general practitioner in the particular field, and on the evidence it was likely that other reputable engineers would have acted in the same manner.

106.  In that case, the defendant agreed the evidence of the plaintiff’s engineering expert (who was a specialist in combustion and incineration who had undertaken detailed design and given technical advice on large incineration plants) was “generally admissible” (ie the defendant could rely on opinion by the plaintiff’s expert in favour of the defendant), but objected to such expert giving expert evidence to criticise the defendant’s performance on the ground that he was too well-qualified to pass an adverse opinion on the performance of general practitioner mechanical and engineering building services engineers (page 362). After citing the aforesaid dicta of Butler-Sloss LJ in Sansom (see paragraph 98 above), the learned judge said as follows at page 363:

“I respectfully agree. I note that even in the case of expert evidence from a member of a different profession the rule is not absolute.

I am satisfied that Mr Hyde [plaintiff’s expert] is a member of the same profession as [the defendant] and therefore there can be no objection as a matter of law to my accepting criticisms which he may make against [the defendant]. As with any witness I must evaluate his evidence with care and take fully into account his own experience. I must be sure that he is not applying too high a standard in reaching his opinion.

To reject Mr Hyde’s professional opinion as a matter of law on grounds that, although a member of the same profession he was over-qualified, would be wrong as a matter of public policy. To go further than Sansom v. Metcalfe Hambleton & Co. would be to encourage parties to try to exclude expert evidence at trial (when it is too late for the pother party to secure another expert) not on the merits but because the qualifications of the expert do not precisely fit the expertise of the individual or firm against who allegations of professional negligence are made.” (my emphasis)

107.  A number of matters were of note in relation to Hammersmith Hospitals NHS Trust & anor, and I am not persuaded this authority established any principles different from those discussed above:

(a)	The defendant conceded that the opinion of the plaintiff’s expert who was a specialist in combustion and incineration and who had undertaken detailed design and had given technical advice on large incineration plants was “generally admissible”. Hence, the question over such expert evidence before the court was more of weight than admissibility.
(b)	The defendant as general practitioner mechanical and engineering building services consulting engineers should be judged by the ordinary standards of its profession, ie the defendant should exercise that degree of care and skill which was ordinarily exercised by reasonably competent members of its profession of the same rank and standing as the defendant tested in an objective way, and it should not be judged by the standards of specialists in combustion, incineration or waste-handling technology (page 346). But such specialist engineers were actually in the same profession as the general practitioner engineers save that the former acquired experience in combustion and incineration through (as in the case of the plaintiff’s expert) undertaking detailed design, giving technical advice on large incineration plants, and being involved in large projects with a large well-known international firm. In that case, there was no question of having an expert of a different (albeit closely-related) specialty giving opinion on the defendant’s acts/omissions, so there was no basis for challenge as to admissibility. Such evidence could not be said to be inadmissible, but the court in weighing the expert’s evidence would have to take into account the expert’s own skill and experience to be sure that he was not applying too high a standard in reaching his opinion.
(c)	The “precise character of the question” on which the plaintiff’s expert gave evidence was whether the defendant’s advice on the suitability of the incinerators and its failure to make further enquiries compatible with responsible body of opinion in relation to the practice of general practitioner mechanical and engineering building services consulting engineers. This could be addressed by the plaintiff’s expert who was in the same profession even though he had a specialist interest in combustion and incineration, and the court’s concern was to make sure not to apply too high a standard. Actually, the plaintiff’s expert eventually conceded under cross-examination that a non-specialist engineer would have been comforted by the manufacturer’s answers and would not have made further checks in the circumstances (page 363).
(d)	As explained by DHCJ To in Zhaung PP Holdings Limited formerly known as China United Holdings Limited (see footnote 11), “…… the standard of care and skill required of a surveyor …… is that standard possessed by a person of ordinary competence exercising the same calling. The standard of reasonable care and skill is usually established by reference to the general practice of the surveying profession ……A surveyor whose conduct is called in question need not possess the highest expert skill. It is well established law that it is sufficient if he exercises the ordinary skill of an ordinary competent man exercising that particular profession. Where a profession embraces a range of views as to what is an acceptable standard of conduct, the competence of the surveyor is to be judged by the lowest standard that would be regarded as acceptable ……” (paragraph 32).

108.  In BMG (Mansfield) Limited & anor v Galliford Try Construction Ltd & anor,[38] there was a serious fire at a shopping centre. The claimant owner alleged that as a result of inadequate fire protection in the roof space and eaves canopies of the centre, the spread of the fire and the consequent damage were far more extensive than it should have been. The defendants were (a) the design and build contractor and (b) the architects engaged by such contractor to perform its design obligations. The dispute/litigation had been ongoing for almost a decade with no sign of conclusion, and Edwards-Stuart J considered it was not surprising or unreasonable for the claimants’ elderly expert to wish to withdraw from the case given his age and the fact he could reasonably have expected the litigation to have been concluded several years earlier. The claimants were therefore granted permission to call expert evidence from a fresh expert on condition that they would disclose any documents/reports received from the retiring expert in which he had expressed opinions on the relevant matters.

109.  In the course of arguments, the defendants, after citing Sansom, suggested that the fresh expert was “not in the relevant field because he is not just an architect but also an expert in fire safety” (paragraphs 40 and 42-43). The learned judge held as follows:

“41. The issues raised in these proceedings call for an expert who is not only an architect, but also one who has knowledge or experience of the requirements for fire protection in buildings such as this shopping centre. To take an extreme example, an architect who had designed little else but domestic conversions or loft extensions would hardly be an appropriate expert for a case such as this. Similarly, it would be of little assistance to the court to have an architect who was familiar with the design of internal layouts of shopping centres but had little or no experience of designing a roof (if such an architect exists).

……

44. In my judgment, the evidence of [the fresh expert] is admissible in relation to the claim against the architects because he is an architect. I do not see how his specialist knowledge of fire precautions can make his evidence as an architect inadmissible. I can see that it may be open to the architects to submit at a trial that his evidence should be given less or little weight because his ability to give evidence as to what a reasonable architect would or should do has been coloured or distorted by his specialist knowledge of fire precautions. But that is a matter that does only to weight, not to admissibility.

45. I accept that the evidence of an expert architect may not be admissible on all the issues relating to [the design and build contractor], but where a contract has assumed design obligations I see no reason why the evidence of an expert architect should not be relevant to some aspects of those obligations. A contractor who is ‘experienced in designing and carrying out work of a similar complexity, scope, nature and size to the Works’, which was the standard that [the design and build contractor’s] contract required, is effectively assuming the role of an architect of similar experience and, in practice, such contractors almost invariably employ or engage architects to do the necessary design work. Ms Sinclair [for the design and build contractor] accepted that a suitably qualified or experienced contractor might be able to give relevant evidence on this question, but I have difficulty in seeing how such a person, if not also an architect, could express an admissible opinion on the discharge of their professional duties by architects employed or engaged by [the design and build contractor].

46. I am, therefore, not persuaded that the evidence of [the fresh expert] will not be admissible at the trial, even though the extent to which he can give evidence in support of the claim against [the design and build contractor] may be more limited than the extent to which he can give evidence in support of the claim against the architects.”

110.  Again, a number of matters were of note:

(a)	The “precise character of the question” before the court on which expert opinion was sought in relation to the defendant architect was whether the design by the defendant architect had inadequate fire protection in the roof space and eaves canopies such that the spread of the fire and consequent damage were more extensive than it should have been. Such issue called for an expert architect who has knowledge or experience of the requirements of fire protection in buildings such as the subject shopping centre.
(b)	The fresh expert was an architect (ie in the same specialty as the defendant architect) with special knowledge of fire precautions, which was therefore relevant to the expert issue as explained in (a) above. There was no question of the opinion from the fresh expert being inadmissible as being from a different specialty. Any possible distortion of his opinion evidence by reason of his special knowledge of fire precautions would go only to the matter of weight.
(c)	But Edwards-Stuart J accepted that opinion evidence from the fresh expert might not be admissible in relation to issues relating to the defendant design and build contractor (other than those issues arising from obligations of the defendant design and build contractor as a result of having assumed the role of an architect), and on those issues a suitably qualified or experienced contractor would be the appropriate expert to give relevant opinion evidence.
(d)	The above is consistent with the principles in Sandra Battersby that the relevance of expertise for opinion evidence was issue-specific in the factual context of the case, ie “the precise character of the question” on which expert opinion was sought, and particular expert evidence could be admissible on some issues and inadmissible on other matters. Likewise, this was reflected in Sansom in which Butler-Sloss LJ said it was not an absolute rule that evidence from those within the same specialty was required to establish the standard expected of professionally qualified men in that specialty and the failure to measure up to that standard. After all, much would turn on the expert issue at hand.

111.  Turning to the facts of the present case for the application of the aforesaid principles, I start by reiterating that in an action brought by a patient, the responsibility for deciding the content of the responsible clinician’s duty of care rests with the court to be assisted with opinion evidence from his or her professional colleagues as experts. Whether such opinion evidence is admissible to provide such assistance is again a matter for the court.

112.  To properly consider the relevance and admissibility of Prof PT’s expert opinion, it is necessary to turn to the “precise character of the questions” to be addressed by the experts on liability and/or causation in the present action. The expert issues were essentially whether there had been delay in diagnosis and/or delay in referral by D1 when measured against the standard of a reasonably competent paediatrician. This was borne out by the pleadings (see paragraphs 8-9 above) and witness statements (see paragraph 11 above). Indeed, the Hui Aff acknowledged that one of P’s principal allegations was Ds’ failure to timely refer P to a proper specialist (eg a paediatric surgeon) despite relevant clinical signs (see paragraph 45 above). Mr Lam SC submitted the alleged delay in referral was the main focus in Prof PT’s opinion (see Answers (2), (4) and (7) in the PT 2^nd Letter in paragraph 32 above) although Mr Tsoi submitted Prof PT also addressed the issue of delay in diagnosis. In my view, Prof PT’s opinion on the failure of earlier diagnosis of colitis was in fact more of a complaint that such failure led to delay in referral for second opinion or to a surgical specialist (see paragraphs 21-23 and 29 of the PT 1^st Report in paragraph 29 above, paragraph 17 of the PT 2^nd Report in paragraph 30 above and P’s pleadings in paragraph 8(a)-(c) above), and indeed the PT 2^nd Report stated that  “[my] main concern has been the delay in seeking extra investigations / expertise when sepsis was unresponsive to empirical treatment, when the source of sepsis was unidentified and when there were new symptoms” (see paragraphs 6 and 15-16 of the PT 2^nd Report in paragraph 30 above). After all, it was not P’s case that earlier diagnosis would have obviated the need for further investigations and referral to specialist in paediatric surgery; rather it was P’s case that earlier diagnosis should lead to earlier further investigations and referral to such specialist. Thus, the “precise character” of the expert issues either directly concerned or had an underlying focus on delay in referral.

113.  In my view, there could not be any dispute that the “precise character” of the above expert issues fell within the ambit of the paediatrics specialty.

114.  Even on delay in diagnosis alone, the relevant expert specialty must be paediatrics. This was illustrated by Tracy Davies (by her Mother and Litigation Friend, Janet Davies) v University Hospital of North Staffordshire NHS Trust & anor.[39] This was a claim against the defendant for failure to arrange a brain scan on 2 occasions in January 2001. Subsequently, the claimant underwent a scan which revealed the presence of a tumour located in the frontal section of the brain. It was accepted that if a scan had been carried out in January 2001, that tumour would have been identified (paragraph 1), it would have been removed and the plaintiff would not have suffered the loss of vision caused by intra-cranial pressure (paragraph 65). On the question of whether or not there was a breach of the duty of care owed by the clinicians to the claimant in failing to arrange for a brain scan or failing to arrange for follow-up of the claimant on discharge from hospital with a view to a brain scan being arranged (paragraph 45), the parties adduced expert evidence from 2 respected consultant paediatricians who had extensive experience in that field and who had acted as consultants in paediatric wards and clinics with direct experience of treating children in such settings  (paragraph 47). Having heard their evidence, Lewis J preferred the evidence of the 1^st defendant’s expert paediatrician, and was satisfied (a) his views on the treatment represented the treatment that would be provided by a responsible body of professional opinion, and (b) that practice (as explained by such expert) did have a logical basis (paragraph 51). The learned judge concluded there was no breach of duty and no negligence (paragraph 67).

115.  Of course, admissibility of opinion of the consultant paediatricians was not disputed in Tracey Davies as they were of the same specialty as that of the 1^st defendant in that case. Even though it was the plaintiff’s contention in that case that earlier investigation and diagnosis might lead to earlier surgical treatment, it was unnecessary to adduce expert evidence from consultant surgeons as the 1^st defendant accepted earlier surgical removal of the tumour would have led to a better outcome (paragraph 65). Nevertheless, this case illustrates that paediatrics was the relevant specialty for delay in diagnosis when the responsible clinician was a paediatrician.

116.  On the more significant question of delay in referral which was the subject of P’s direct complaint and which underlined the compliant of delay in diagnosis, I need not look further than Sansom which explained why on the “precise character of the question” the relevant specialty was paediatrics (as chartered surveyor in Sansom) and not paediatric surgery (as structural engineer in Sansom). The paediatric surgeon would have been aware of paediatricians and other medical practitioners who made referrals to and/or called on him to further investigate and treat children patients, but the paediatric surgeon would not have known of those who did not make referrals to and/or call on him, nor whether it was reasonable or not reasonable not to do so.

117.  In my view, this was demonstrated by (a) Prof PT’s own opinion that when the fever did not respond to empirical treatment and when there were additional (vomiting and diarrhea) and evolving (abdominal distension) symptoms, coupled with laboratory evidence of ongoing sepsis (infection), it would be reasonable to expect a referral for a second opinion or more investigations (see paragraph 29 above), but there was lack of urgency on the part of D1 in referring P to surgical consultation (see paragraph 30 above), and (b) his acknowledgment in the PT 2^nd Report from his perspective as a paediatric surgeon (who was trained to manage abdominal emergencies and to be risk-averse) that abdominal distension was a serious clinical feature whereas a paediatrician would be more focused on other abdominal signs as reassuring clinical features that did not warrant further investigations or a second opinion (see paragraph 30 above).

118.  More importantly, Prof PT in the PT 2^nd Report stated he had a different approach from Dr CHB (paediatrician) “towards new abdominal signs and symptoms in the presence of sepsis of unknown origin which had been unresponsive to empirical treatment” (see paragraph 30 above), and in the PT 2^nd Letter that “[from his] perspective as a specialist who gets referrals from medical practitioners and paediatricians for abdominal emergencies, his referral is relatively late in comparison with other referring doctors when faced with similar clinical features. Accordingly, [D1’s] actions fell below the standard of a reasonable competent paediatrician in the aspect of timely referral to a relevant specialist” (my emphasis) (see paragraph 32 above).

119.  The above showed that Prof PT regarded P’s new abdominal signs and symptoms (especially abdominal distension) in the presence of sepsis of unknown origin that was unresponsive to empirical treatment as serious clinical features significant enough to warrant referral for a second opinion and further investigations, but that was because he was trained as a surgeon to manage abdominal emergencies and to be risk-averse. Obviously, in giving such opinion Prof PT was looking from the perspective of paediatric surgeons at the receiving end of such referrals. This was made clear by what Prof PT said in the above paragraph, ie that the referral by D1 was late compared with other referrals he received from other paediatricians and medical practitioners in relation to patients with similar clinical signs, and he explained that “accordingly” (ie this was the reason why) he opined D1’s “actions fell below the standard of a competent paediatrician in the aspect of timely referral to a relevant specialist”.

120.  In my view, such opinion fell foul of the guidance in Sansom, that on the “precise character of the question” of timely referral to a relevant specialist, it was the views of paediatrician (or chartered surveyor) and not those of the paediatric surgeon (or structural engineer) that would be relevant and admissible because the latter would only be able to say what he knew from the receiving end and not from the requisite standard at the referring end. Indeed, Prof PT himself recognised this difference because he acknowledged the different approach between him (as a paediatric surgeon who must be at the receiving end) and Dr CHB (as a paediatrian who must be at the referring end in the context of the present case) towards new abdominal signs and symptoms (including abdominal distension) in the presence of sepsis of unknown origin that was unresponsive to empirical treatment as indications for referral.

121.  Mr Tsoi submitted that notwithstanding the correct specialty was paediatrics and not paediatric surgery, Prof PT had the relevant expertise to speak on the standard of care of a paediatrician, and hence Mr Lam SC’s criticisms only went to the question of weight of Prof PT’s opinion. It was said that Prof PT was by qualification (as opposed to registration of specialties) a Fellow of Royal College of Paediatrics and Child Health (FRPCH), and he was also the “examinerof MBChB Paediatrics (U of Liverpool)”, which position was to examine the competence of paediatricians, so in the absence of contrary expert evidence it would be difficult for any lawyer (eg Chan) to undermine Prof PT’s ability to assess the conduct of D1 in the present action.

122.  I reiterate the guidance in the above authorities that the suitability of an expert’s expertise is tied to the “precise character of the question” that he is required to deal with, and is not to be considered generally. The reasoning in Sansom discussed above explained why Prof PT did not have to relevant expertise to address the particular expert issues herein. Indeed, some of the reasons given by Prof PT to explain why he claimed to have “the relevant qualifications and training to comment on the standard of care of a paediatrician” were that “[he interacts] with paediatricians on a daily basis in [his] professional practice”, and that each specialty “should know sufficiently the other to be able to provide seamless care”, but such reasons lent weight to the concern that he would be speaking from the receiving end of referrals by paediatricians, which approach was rejected in Sansom in that the issue must be viewed from the perspective of a specialist in paediatrics in the same position as D1 at the relevant time to consider whether and when it would be reasonably necessary to refer P to a paediatric surgeon.

123.  Further, the fact that Prof PT was a Fellow of the Royal College of Paediatrics and Child Health (FRPCH) did not show/prove he practised as a paediatrician; rather, his curriculum vitae showed that he all along practised as a paediatric surgeon. Further, although Prof PT was a university examiner of “MBChB Paediatrics (U of Liverpool)”, it was in 1988 (ie more than 30 years ago) when he was “Senior Lecturer (Paediatric Surgery) in the Institute of Child Health” (my emphasis) (see Answer (5) of the PT 2^nd Letter in paragraph 32 above). Plainly, his academic experience was also focused on paediatric surgery. More importantly, the expert issues, especially in relation to the delay in referral, concerned clinical practice matters of paediatricians rather than, say, primary knowledge of relevant anatomy, physiology and treatment procedures, and I am afraid this was where Prof PT’s expertise gave rise to legal concern in the context of the present case despite his rich experience as a paediatric surgeon. Whilst I accept Prof PT’s expertise in paediatric surgery would not bar him absolutely from giving expert evidence on other expert issues where the responsible clinician is a paediatrician, I am not persuaded his opinion is relevant and/or admissible on the particular expert questions in the present case.

124.  The authorities cited by Mr Tsoi would not detract from the above conclusion. Where those authorities suggest that the opinion of experts who are over-qualified goes to weight rather than admissibility of their opinion (eg medical expert with lengthy experience in the NHS as compared with one with lesser level of NHS experience in C (by his father and litigation friend F) in paragraph 74 above, the “specialist” consultant neuroradiologist as compared to “mere” radiologist in Mr Dennis Lee in paragraphs 79-80 above, the engineer with particular experience in combustion and incineration as compared with general practitioner mechanical and building services engineer in Hammersmith Hospitals NHS Trust & anor in paragraphs 105-107 above, and the architect with specialist knowledge of fire precautions as compared with architect with design obligations in BMG (Mansfield) Limited & anor in paragraphs 108-110 above), the experts were members of the same profession/specialty as the defendant in question except they might be said to be “over-qualified”. But there is no need for the expert to fit the precise skill and experience of the person against whom allegations of professional negligence are made, and such expert evidence does not fall foul of the guidance in Sansom. Any suggestion of “over-qualification” goes to the weight of such opinion evidence.

125.  Where the authorities cited by Mr Tsoi suggest that the experts engaged are of different specialty/profession from the defendant, it appears that their opinion is admissible in relation to the “particular character” of the expert issue that is addressed, eg the consultant neurologist in Sandra Battersby had requisite specialised training, study and experience in the anatomy, physiology and pathology to allow him express opinion on surgical procedure to an area of the anatomy (and based in part upon matters of physiology) in which he had considerable training, study and experience (see paragraphs 75-78 above), and the geotechnical engineering expert in Co-operative Group Limited was not asked to address on structural matters (on which the expert accepted he could not give opinion) but on the professional practice of civil and structural engineers who had undertaken to handle geotechnical issues that had arisen on the project (see paragraphs 101-104 above), which in my view rendered such geotechnical engineering expert to be similar to the “over-qualified” experts discussed in the above paragraph.

126.  It is therefore unsurprising for the courts in the above authorities to find such expert opinion would go to the question of weight and not to admissibility. However, the nature of expertise and “precise character” of the expert issues in those cases were a far cry from the particular circumstances of the present case, and I am not persuaded the opinion of Prof PT was admissible on the expert issues on liability in the present case.

(c)  Standard Issue

127.  Answers (2) and (7) in the PT 2^nd Letter (issued after Ds filed the Summons) claimed that the requisite standard of care adopted by Prof PT in the PT 1^st Report was that expected of a reasonably competent paediatrician on the aspect of timely referral (see paragraph 32 above). However, whether Prof PT had adopted such standard was not for him to assert, but for the court to decide upon examination of the expert opinion in the PT 1^st/2^nd Reports as a whole. Mr Tsoi asked me to do so “against the evidence as a whole”. In this respect, whilst the PT 1^st/2^nd Letters would be relevant, I have to bear in mind that experts are required to reduce their opinion in writing (see Order 38 rule 37(1) of the RHC), so any observations by Hui and Chan in their affidavit evidence could not be taken too far.

128.  I should start by dealing with a short point. Mr Lam SC pointed out that 1 of the 2 references Prof PT cited in the PT 2^nd Report was an article published in Paediatric Surgery International 2006. Mr Tsoi noted the authors for both articles were attached to the department of paediatrics in a children’s hospital in Taiwan, so on the face of such articles the authors were not paediatric surgeons. I am not persuaded that these matters would be relevant. A contributing author to a paediatric surgery publication need not be a paediatric surgeon, and a member of the department of paediatrics in a hospital need not be merely a paediatrician. It is the opinion of Prof PT that would matter, and not the learned articles he cited to support his views.

129.  Mr Tsoi submitted that Prof PT correctly applied the Bolam test by assessing the conduct of D1 against the reasonable standard expected of a reasonably competent paediatrician as opposed to the standard expected of a paediatric surgeon. Prof PT (a) opined it was not unreasonable for “primary physicians” to treat a patient for common diseases and (b) referred to the persistence of certain clinical features that should alert “a competent doctor” to underlying gastrointestinal conditions that would warrant further investigations and/or referral for a specialist opinion in paragraphs 21 and 29 of the PT 1^st Report (see paragraph 29 above), and further (c) opined it should be within a “paediatrician’s clinical experience” to recognise pneumoperitoneum on AXR or CT scan, and (d) opined P’s inability to communicate would not influence “the Paediatrician’s ability” to arrange an earlier abdominal x-ray, ultrasound examination or surgical consultation, and one might argue “the Paediatrician” should have heightened awareness of disease progression and complication such as to have more urgency in arranging investigations and referrals in paragraphs 16-17 of the PT 2^nd Report (see paragraph 30 above). On the other hand, Lam SC submitted that the expert opinion Prof PT gave in the PT 1^st/2^nd Reports showed he failed to apply the appropriate standard of care.

130.  Turning first to the PT 1^st Report, the matters in paragraph 129(a)-(b) above merely stated general matters which I doubt Ds would contest, eg a competent paediatrician should know when persistent underlying gastrointestinal conditions would warrant further investigations and/or referral for specialist opinion, and a primary paediatrician can treat patients for common diseases. Rather, the key question was Prof PT’s mindset and considerations when he came to address the particular questions as to when and under what circumstances D1 as paediatrician should have called for further investigations and/or referral to specialist surgeon.

131.  Upon giving his views in paragraphs 21-22 and 29 of the PT 1^st Report, Prof PT opined and concluded in paragraph 23 thereof that on a balance of probabilities D1 had fallen below “the requisite standard of care in the ways listed in 7(a-g) of your instructions” (see paragraph 29 above), but the letter of instructions merely asked Prof PT to opine on whether D1 had fallen below the “requisite standard of care” in the listed ways without specifying what the standard of care was (see paragraph 14 above).

132.  More importantly, Prof PT gave opinion in paragraphs 21-22 and 29 of the PT 1^st Report on what to make of the “underlying GI conditions”, and in paragraph 29 thereof on the need to make referral for a second opinion and more investigations when (a) the fever did not respond to empirical treatment, (b) there was additional (vomiting and diarrhea) and evolving (abdominal distension) symptoms, and (c) there was laboratory evidence of ongoing sepsis (infection) (see paragraph 29 above). As explained in the above paragraph, Prof PT in the PT 1^st Report did not spell out what was the “requisite standard” he applied when he gave the aforesaid opinion,[40] but he elaborated on his approach in the PT 2^nd Report.

133.  In paragraph 8 of the PT 2^nd Report (see paragraph 30 above), Prof PT explained the difference in approach between him (in the PT 1^st Report) and Dr CHB (in the CHB Report) towards “new abdominal signs and symptoms in the presence of sepsis of unknown origin which has been unresponsive to empirical antibiotic treatment”, ie (a) “[Dr CHB] (a paediatrician)” focused more on the abdomen being soft and the presence of bowel sounds as reassuring clinical features, but (b) abdominal distension was considered a serious clinical feature by “surgeons (like [Prof PT])” who “are trained to manage abdominal emergencies and are risk-averse: even small probability of a high risk is taken seriously”. Then, paragraph 9 of the PT 2^nd Report went on to note that whilst Dr CHB opined the delay in ordering ultrasound abdomen was justified,[41] Prof PT opined the “surgical consensus” would be that surgical conditions like impending gut perforation, intussusception and volvulus were surgical emergencies that could not be delayed for over 12 hours.

134.  The above explanation was from Prof PT himself on how he approached the presenting gastrointestinal signs/symptoms in P’s clinical picture, which was the very basis on which he formed his opinion in the PT 1^st Report. What Prof PT frankly said was that although he (as paediatric surgeon) and Dr CHB (as paediatrician) looked at the same presenting gastrointestinal signs/symptoms in P’s clinical picture, he did so from the perspective of a paediatric surgeon (receiving end) which accounted for the difference in opinion between him and Dr CHB who did so as a paediatrician (referring end) in coming to his opinion on the issue of delay in diagnosis/referral. The elaboration Prof PT gave in Answer (1) of the PT 2^nd Letter that impending gut perforation, intussesception and volvulus being surgical emergencies are both “surgical consensus” and “knowledge expected of qualified medical practitioners including paediatricians” (see paragraph 32 above) does not address the precise expert issue of when, in light of the presenting clinical features, D1 as a paediatrician should refer for a second opinion or further investigations.

135.  Prof PT further elaborated on this in Answer (2) of the PT 2^nd Letter to the effect that “[from Prof PT’s] perspective as a specialist who gets referrals from medical practitioners and paediatricians for abdominal emergencies”, D1’s referral of P to QEH was relatively late in comparison with other referring doctors when faced with similar clinical features, “[accordingly, D1’s] actions fell below the standard of a reasonably competent paediatrician in the aspect of timely referral to a relevant specialist”. Although Prof PT claimed to have applied the standard of a reasonably competent paediatrician, he “accordingly” came to the view that D1’s conduct fell below such standard from his interaction with paediatricians and other doctors on daily basis (see Answer (3) of the PT 1^st Letter and paragraph 31 above) and from his receiving referrals from padiatricians and medical practitioners for abdominal emergencies with the same clinical features, which referrals were made earlier than D1’s referral of P to QEH (see Answer (2) of the PT 2^nd Letter and paragraph 32 above). Thus, Prof PT was reiterating that he was looking at the matter from the paediatric surgical receiving end rather than from the paediatric referring end. In Part XII(b) above, I have explained why this was an inappropriate and inadmissible approach.

136.  Mr Tsoi’s reliance on the matters in paragraph 129(c)-(d) above again would not ameliorate my reservations over Prof PT’s opinion referred to above. Those matters were general statements, and I doubt whether Ds would dispute that paediatricians can read abdominal x-ray or CT scan to recognise pneumopertoneum and/or a child’s inability to communicate his/her complaints should not influence a paediatrician’s ability to make timely investigation or referral. Likewise, it was said in Answer (4) of the PT 2^nd Letter (see paragraph 32 above) that “the training of a paediatric surgeon covers his/her professional relationship with other relevant specialties including paediatrics”, so “a reasonably competent paediatric surgeon should know when to refer his/her patient to a paediatrician and vice versa”, which again was a general statement. They were not the expert questions in issue, and did not allay concerns over Prof PT’s explanations on how he approached the “precise character” of the expert issues as outlined above.

137.  In the circumstances, I find Prof PT’s frank explanations in the PT 2^nd Report as to his mindset and approach more illuminating that the mere assertions in Answers (2) and (7) of the PT 2^nd Letter referred to in paragraph 127 above.

138.  By reason of the above matters, I am not persuaded Prof PT applied the correct standard when he expressed his opinion in the PT 1^st/2^nd Reports. In my view, this went directly to the question of admissibility rather than weight for the trial judge. In my view, the wrong approach undermined the fundamental pith and substance of the PT 1^st/2^nd Reports, and the opinion expressed therein on the issues of liability must be withdrawn.

XIII.  CAUSATION ISSUE

139.  Both Mr Lam SC and Mr Tsoi agreed that I am only concerned with expert opinion on causation as to liability and not causation as to quantum, and both of them agreed the issues of liability and causation were intertwined. Mr Lam SC submitted that even if Prof PT had expertise to comment on causation, it would be beside the point because it was common ground that the experts on liability should deal with the issues of standard of care and causation in one go.

140.  But Mr Tsoi argued that although the issues on liability and causation are intertwined, they remained as distinct issues to be addressed by expert evidence, especially when P’s case was that delayed referral for specialist treatment led to a less favourable outcome (see paragraph 10 above). Mr Tsoi submitted that the causation issue would turn on the hypothetical conduct of a third party specialist.

141.  In Gouldsmith v Mid Staffordshire General Hospitals NHS Trust,[42] the plaintiff suffered loss of the digits of her left (dominant) hand due to occlusions to blood vessels during the course of treatment for problems with her left hand. She sought damages for medical negligence against the hospital.

142.  The plaintiff had a history of suffering from vascular problems and had been taking anti-coagulants. There were periods of in-patient treatment and periods of improvement followed by deterioration of the condition of the left hand. The pain became worse and the possibility of amputation was discussed. At the trial on liability, the trial judge rejected the hospital’s argument that the anti-coagulant treatment had been adequate and found the hospital to be negligent, but he concluded the negligence had not caused the plaintiff’s injuries. It was the plaintiff’s case that she should have been referred to a specialist tertiary unit when problems with her left hand were encountered, and had she been so referred, appropriate surgery would have been conducted and several digits would have been saved. So she appealed.

143.  The issue before the English Court of Appeal was how to approach the matter of causation in medical negligence cases where an injury arises because of failure to ensure the hypothetical intervention of a third party specialist who would have forestalled the process leading to the injury. In that case, the trial judge found the plaintiff’s symptoms were caused by an embolisation at her clavicle (rather than a thrombotic problem in her forearm as suggested by the defendant’s expert in surgery), and because of such embolisation, the responsible surgeons were found to be in breach of duty in not referring her to a specialist tertiary unit. But the trial judge noted no evidence was led as to what would have happened at a specialist tertiary unit (eg which specialist tertiary unit would have been involved, whether surgery would have been undertaken there and/or whether “every specialist exercising the proper standard of care would have operated on the [plaintiff]” – paragraph 22), so causation was not made out.

144.  This was reversed by a majority of the English Court of Appeal (with Maurice Kay LJ dissenting), who concluded that the failure to refer the plaintiff to a specialist tertiary unit had been negligent and had been the cause of the injury she suffered. The 2-stage approach under the Bolam test posed 2 questions: (a) had the plaintiff been referred to a specialist tertiary unit was it likely that a vascular specialist would have carried out surgery on the lesion, and (b) if not, would the vascular specialist have been negligent in not carrying out such operation. The majority held that in respect of (a) above (being a factual question), the evidence that most specialist units would have carried out surgery was sufficient to show that a specialist tertiary unit would, on the balance of probabilities, have carried out surgery. Thus, the issue in (b) above would not arise. Maurice Kay LJ in his dissenting judgment held that in the absence of evidence (such that the identity of the specialist unit or surgeon who would have seen the plaintiff was unknown), he was unable to say on (a) above that on the balance of probability the lesion would have been operated upon by the doctors at the specialist tertiary unit, and it was just as likely that a vascular surgeon exercising the proper standard of care would have formed the view that nothing could be served by operating on the lesion.

145.  Mr Tsoi drew my attention to the commentary on the case at page 374 as follows:

“The issue of causation, in cases of negligence by omission, raises the difficulty of identifying the hypothetical ‘might-have-been’. This difficulty is acute when the hypothetical actor, whose actions might have been determinative, is neither a party nor a witness in the action, and thus gives no evidence. Cases such as the present, where but for negligence a patient with a progressive condition would have been referred to an unidentified specialist who might have been offered treatment which might or might not have succeeded, raise particular difficulties.

……

In such cases as the present one, of hypothetical referral to a third party who is not in court to explain what could or might have been done, is not defending itself and still less is seeking to take advantage of hypothetical negligence, it is perhaps wiser simply to consider what the third party should have done as part of the evidence of what it would have done: in other words, to concentrate solely on whether the claimant can prove, in all the circumstances including the normal practice of medicine, whether the injury was more likely than not to have been avoided on referral (in this case) to a specialist.” (my emphasis)

146.  Mr Tsoi submitted it was therefore incumbent upon P to adduce clear and sufficient expert evidence to address the issue of causation in relation to the hypothetical conduct of a paediatric surgeon. He further reminded that paragraphs 66(5) and 67(10) of the Practice Direction 18.1 for the Personal Injuries List also recognised this distinction between expert evidence on liability and expert evidence on causation by requiring the parties in all medical negligence cases to serve “a copy of any expert medical report relied upon as to liability and causation” (my emphasis).

147.  In my view, the issue of causation in the present case is less complicated than the one in Gouldsmith for D1 did refer P to QEH for surgical consultation, and surgery did take place. But given the alleged negligence in the present case was delay in diagnosis/referral, it is still relevant and necessary for P (who carried the burden of proof) to adduce evidence on the questions of (a) what action would have been undertaken had an earlier diagnosis and referral been made, (b) would that action have altered the course of the injury, and (c) if nothing different would have been done, or if the answer to (b) above is in the negative, was that below the standard of care that could be expected. Such evidence was especially pertinent when Ds by their Defence averred that other forms of treatment instituted in any other time frame would change the natural course of the disease was speculative as P suffered from infective colitis and was already prescribed with strong and broad spectrum antibiotics which were for serious infections (see paragraph 9(i) above). And I agree with Mr Tsoi that paediatric surgery expert evidence is that relevant specialty (it being a recognised specialty) to address these questions for establishing causation.

148.  Prof PT in Answer (8) in the PT 2^nd Letter said that “ ...... [as] a specialist in surgery, a paediatric surgeon has more experience in the entire spectrum of early to late diagnosis and its consequences” (my emphasis) (see paragraph 32 above). Prof PT gave opinion on causation in paragraph 30 of the PT 1^st Report that  “[earlier] diagnosis may result in avoidance of surgery or less extensive surgery …… Avoidance of bowel perforation by earlier surgery could also result in less short- and long-term morbidity such as future risk of intestinal adhesions” (see paragraph 29 above), and in paragraph 14 of the PT 2^nd Report that “…… [the]clinical window to detect serious gut pathology (toxic megacolon)before the gut perforation was however not fully made use of: while there are mitigating factors to argue for a more lenient interpretation of the clinical events …… the clinical outcome remains unsatisfactory for the patient” (see paragraph 30 above).

149.  Mr Tsoi submitted that Prof PT’s expert opinion served the dual purpose of establishing liability and causation, and the court would likely attribute more weight to the opinion of a paediatric surgeon than that of a paediatrician on the issue of causation. Mr Lam SC submitted it was common ground that the experts on liability should deal with the issues of standard of care and causation in one go, and the relevant specialty should be paediatrics and not paediatric surgery.

150.  Whilst both parties prefer to have the same experts address the issues of liability and causation, they differed as to whether such experts should be paediatricians or paediatric surgeons. I have found that paediatrics is the relevant specialty to address the expert issues on liability, but the expert issues on causation as to liability should be viewed from the paediatric surgery perspective. Bearing in mind it was the common stance of both Mr Tsoi and Mr Lam SC that it was not for this court to blue-pencil the PT 1^st/2^nd Reports, and more importantly, given my conclusion on the Expertise and Standard Issues that the opinion in the PT 1^st/2^nd Reports on expert issues as to liability must be withdrawn, Prof PT’s opinion in the PT 1^st/2^nd Reports on expert issues as to causation that rested on his opinion on matters of liability (to be withdrawn) could no longer stand, and thus the PT 1^st/2^nd Reports as a whole must be withdrawn.

151.  I must make clear that such conclusion does not in any way reflect on the expertise of Prof PT, who I accept is respected and has vast experience in his own specialty of paediatric surgery. My conclusion serves to identify the appropriate specialties and expertise for the particular issues in the present litigation, and it behoves the legal representatives to give clear guidance to the experts on the correct approach.

XIV.  CASE MANAGEMENT: FURTHER EXPERT DIRECTIONS

152.  As regards the suggestion that there be medical experts for one specialty on both issues of liability and causation, whilst I accept case management is to serve the underlying objectives of cost-saving economy and efficiency, the court must also be astute to ensure the primary aim of the exercise of case management powers to secure the just resolution of disputes in accordance with the substantive rights of the parties is achieved.

153.  It is therefore appropriate to grant expert directions to give effect to this decision by giving leave to the parties to adduce expert medical evidence on liability in the specialty of paediatrics and on causation in the specialty of paediatric surgery. As to whether the parties consider Prof PT and Dr CHB can have any role as experts in rendering reports on the requisite disciplines even though their own specialities did not fit precisely into those disciplines, it is for the parties to carefully consider their suitability or otherwise according to the Bolam test and their expertise in light of the particular expert issues to be addressed. I note, for example, that Prof PT opined that “[earlier] diagnosis may result in avoidance of surgery or less extensive surgery ……” was a medical knowledge expected of a reasonably competent medical practitioner, irrespective of whether he/she was a paediatric surgeon or paediatrician (see Answer (8) of the PT 2^nd Letter in paragraph 32 above). But this should be revisited in light of the discussions in this decision, and the parties will also have to consider the risk of challenge to the experts’ experience and expertise at trial if they are called upon to address expert issues on matters outside (albeit related to) their own specialties.

XV.  CONCLUSION

154.  In the circumstances, I allow the Appeal, set aside the Master Order, and order that the PT 1^st/2^nd Reports be withdrawn and not to be adduced at the trial of the present action. Given my conclusions above on the appropriate specialties for expert evidence on liability and on causation, and the fact that the plaintiff is legally aided such that time is required for seeking approval for nomination and/or engagement of medical experts, I direct the parties to jointly write to this court within 35 days from the date hereof to propose (a) expert directions in light of paragraph 153 above, and (b) consequential case management directions. The parties should also take this opportunity to regularise the matters in paragraph 23 above to avoid future confusion.

155.  There is no reason why costs should not follow event. I therefore grant a costs order nisi that P shall pay Ds’ costs of and occasioned by the Summons and the Appeal (including all costs reserved if any) to be taxed if not agreed, and P’s own costs be taxed in accordance with Legal Aid Regulations.