Expert Witness Journal Issue 67 June/July 2026 - Flipbook - Page 26
“rule in” signs for FND and symptoms can also be
features of malingering / factitious disorder. It
will be appreciated that with this rather confusing
terminology, there is scope for cross-examiners to
have a 昀椀eld day. Some experts, sensibly perhaps,
stick to the descriptive term “Functional”, but
should de昀椀ne what they mean. Finally, while DSM5
recognises that Functional Neurological Symptom
Disorder may arise anew after even minor physical
trauma, the aetiology of the condition involves
mainly factors present from early life.
necessarily the same health concerns) prior to
the injury. The aetiology of the condition mainly
involves factors present in early life, including
family/genetics, personality traits, early experience
of illness, abusive experiences. Scales such as the
PHQ15 and SSD12 (Somatic Symptom Disorder-B
Criteria Scale) are sometimes used to screen for or
quantify symptoms. Three published meta-analysis
indicate the treatment is amenable to Cognitive
Behavioural Therapy.
Table 3 Somatic Symptom Disorder in
DSM 5 - requires A,B and C
According to ICD-11, “Factitious disorders are
characterised by intentionally feigning, falsifying,
inducing, or aggravating medical, psychological, or
behavioural signs and symptoms or injury in oneself
or in another person associated with identi昀椀ed
deception”. Sometimes a person deliberately induces
additional symptoms or signs with an established
illness, injury or wound. A distinction is made
between Factitious disorder and deliberate feigning
of symptoms for material gain (ie Malingering,
which is not considered a Psychiatric disorder).
But in a medicolegal context, a person’s motives
will often be di昀케cult to determine and as always,
reliability of a person’s account is a matter for the
court. Tread carefully here!
A. One or more somatic symptoms that are
distressing or result in signi昀椀cant disruption of
daily life.
B. Excessive thoughts, feelings, or behaviours
related to the somatic symptoms or associated
health concerns as manifested by at least one of
the following:
1.
Disproportionate and persistent
thoughts about the seriousness of
one’s symptoms.
2.
Persistently high level of anxiety about
health or symptoms.
3.
Excessive time and energy devoted to
these symptoms or health concerns.
C. Although any one somatic symptom may not
be continuously present, the state of being
symptomatic is persistent (typically more than
6 months).
Dr Stephen Davies
Functional Neurological
Symptom Disorder
Consultant Psychiatrist (General Adult & Liaison)
based in South Wales
This requires one or more alterations in voluntary
motor or sensory function,but that clinical 昀椀ndings
are incompatible with neurological or physical
disease. Presentations include seizure-like activity,
tremor, dystonia, visual symptoms etc. In DSM-5, the
term Functional Neurological Symptom Disorder
(FNSD) has replaced the term Conversion Disorder.
There is no assumption of Psychological causation
and no requirement for underlieing stress. There
have been several publications by an Edinburgh
group using a slightly di昀昀erent term, Functional
Neurological Disorder (FND not FNSD). This term
emphasises that this is not a diagnosis of exclusion,
but rather that there are speci昀椀c “rule in” signs and
symptoms. The ICD-11 uses a di昀昀erent term again “Dissociative neurological symptom disorder” and
does not require rule-in signs or symptoms to be
present. It should be added that the Psychiatric
classi昀椀cations make a make a distinction between
FNSD/DNSD on the one hand and Factitious
Disorder / Malingering on the other. The concept
used by neurologists of “FND” does not make this
distinction explicitly and many of the published
EXPERT WITNESS JOURNAL
MB, BCh, MSc, MRCPsych
Dr Davies has 25 years of experience as a Consultant Psychiatrist. This
includes extensive work assessing Psychiatric problems relating to
physical disease and trauma. Dr Davies currently works weekly
clinical sessions for an NHS PTSD service and NHS Veterans Wales.
He produces around 80 reports per year on personal injury
cases involving PTSD, Depression, Psychiatric aspects of Road
Traffic Accidents and workplace injuries, Chronic Pain, Burns and
MoD cases.
Appointment availability - usually around 4 weeks in Cardiff. By
arrangement claimants can be seen in Swansea, Carmarthen, Bristol
or London.
Telephone: 01792 260 006
Email: secretary@daviesmedicolegal.com
Website: www.drsdavies.co.uk/medico-legal-reports/
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JUNE 2026
