Diagnosis by machine

I am pleased to let BMJ readers know that efforts to build tools to
help
physicians with diagnosis have certainly not ‘fizzled out’ but, in fact,
are very
much thriving.

Isabel is one such tool that was inspired by my own daughter’s near
fatal
misdiagnosis in 1999. The original hypothesis was to produce a tool that
could provide the clinician, at the point of care, with a list of likely
diagnoses
for him to consider when given a list of signs and symptoms. Today,
Isabel
is web based, readily available and covers 10,000 diseases and all age
groups. It has been extensively validated with major studies being carried
out
in NHS hospitals and paid for by the DH. It is now being used in daily
practice
by many top hospitals in the US to improve diagnosis quality and reduce
clinical risk.

The major differences between Isabel and the earlier attempts at
diagnostic
tools are essentially the technology then available and the role they were

intended to perform. The old technology meant that they took 20 minutes to

use-impractical in a busy clinical setting. The role intended was that of
an
expert system giving rise to the idea that they would “supplant doctors”.
This
was always clearly a self-defeating aim. Isabel’s intention has always
been to
help the physician in the process of reaching a diagnosis by providing
him, in
seconds, with a list of likely diagnoses to consider together with
supporting
knowledge. The clinician remains very much the expert but the burden on
memory is relieved, in fact the clinician becomes a better expert.

Clinicians do an outstanding job on a daily basis with the time and
resources
they are provided with. However, in the face of an increasing body of
evidence of misdiagnosis and why these errors happen, it is clear that
diagnosis quality can be improved. Since diagnosis is the most fundamental

upstream event that determines subsequent treatment and medication, it is
incomprehensible that more attention is not focused on how well this
function is carried out. Airline pilots routinely use a checklist for take
off why
should clinicians not use a checklist for diagnosis? The stakes are too
high
for patients to rely almost exclusively on a doctor’s memory. Agreed, the
tools were not good enough 30 years ago but they certainly are today.

Competing interests:
Jason Maude is Co Founder and
CEO of Isabel Healthcare that
develops and markets the Isabel
system