Expert Witness Journal Issue 66 April 2026 - Flipbook - Page 20
For expert witnesses, the judgment underscores
the importance of precision. When citing metaanalyses, it is essential to be clear whether the
evidence is aggregate or individual participant
data, and to explain why that distinction matters.
Experts should identify the speci昀椀c subgroups
their conclusions depend upon, including their
size and statistical stability, and ensure that study
populations resemble the claimant’s clinical pro昀椀le.
Do not rely on biological plausibility to bridge gaps
in the quantitative evidence. Where the data show a
trend but the con昀椀dence interval crosses unity, say
so plainly.
Taken together, the judgment reinforces a central
lesson for experts and instructing solicitors alike:
the strength of an expert opinion lies not in its
con昀椀dence, but in whether the evidence relied upon is
methodologically capable of supporting it. As courts
become more sophisticated in their engagement
with medical evidence, those who understand these
distinctions will be better placed to build cases that
withstand scrutiny - and to identify, early on, those
that may not.
Contact
carolina.stamboulid@episteme-consulting.co.uk
For solicitors, the case highlights the value of early
methodological scrutiny of the evidence base.
Where causation depends on subgroup analyses,
rare outcomes, or extrapolation between related
conditions, careful examination of the underlying
scienti昀椀c assumptions at an early stage can prevent
unrealistic case valuation and late-stage evidential
collapse. The evidential weaknesses that determined
the outcome in De Francisci were present in the
literature from the outset. Identifying them before
substantial costs have been committed allows
for more realistic case evaluation and, where
appropriate, earlier resolution.
Chris Dawson BSc MBBS FRCS MS LLDip
Consultant Urologist
Mr Dawson is a Consultant Urologist with over 29 years’ experience. He has
formal training in personal injury and medical negligence reporting and
completed the Bond Solon Expert Witness Course in 2006. In 2008 he
completed a Diploma in Law at the College of Law in Birmingham.
Mr Dawson has over 22 years of medico legal report writing and expert witness
work and has completed over 2000 reports, He has completed numerous Fitness
to Practise reports for the General Medical Council.
He is the author of the ABC of Urology, now in its 3rd edition, and also co-edited the Evidence for Urology
which won first prize in the urology section of the BMA Medical Book Competition in 2005.
Mr Dawson is happy to accept instructions for personal injury, clinical negligence and condition and
prognosis reports.
Telephone: 07711 584939
Email: expertwitness@chrisdawson.org.uk
Fitzwilliam Hospital, Milton Way, South Bretton, Peterborough, PE3 9AQ
www.chrisdawson.org.uk
EXPERT WITNESS JOURNAL
18
APRIL 2026
