Transcript Evidence based medicine

Evidence based medicine
Learning and Teaching
What evidence-based medicine
is:
Evidence-based medicine is the
conscientious, explicit and judicious use of
current best evidence in making decisions
about the care of individual patients. Its
philosophical base dates back to the
sceptics of post-revolutionary Paris
(Bichat, Louis, Magendie).
What evidence-based medicine
is:
The practice of EBM requires the integration
of
 individual clinical expertise
with the
 best available external clinical evidence
from systematic research.
What evidence-based medicine
is:

Individual clinical expertise: the increasing
proficiency and judgement that individual clinicians
acquire through clinical experience and clinical
practice.
• reflected especially in more effective and efficient
diagnosis, and
• in the more thoughtful identification and
compassionate utilisation of individual patient’s
predicaments, rights, and preferences in making
clinical decisions about their care.
What evidence-based medicine
is:

Best available external clinical evidence:
• clinically relevant research, often from the
basic sciences of medicine, but especially
from patient-centred research into the
accuracy and precision of diagnostic tests
(including the clinical examination), the power
of prognostic markers, and the efficacy and
safety of therapeutic, rehabilitative, and
preventive regimens.
What evidence-based medicine
is:
 External clinical evidence has a short
doubling-time, and both invalidates
previously accepted diagnostic tests and
treatments and replaces them with new
ones that are more powerful, more
accurate, more efficacious, and safer
What evidence-based medicine
is:

Good doctors use both individual clinical expertise
and the best available external evidence, and neither
alone is enough.
• Without the former, practice risks becoming
evidence-tyrannised, for even excellent external
evidence may be inapplicable or inappropriate for
an individual patient.
• Without the latter, practice risks becoming rapidly
out of date, to the detriment of patients and
patient-care.
What evidence-based medicine
is:
 this definition also helps us identify and
understand what evidence-based medicine
is not.
EBM is neither old-hat nor
impossible to practice:

The former argument falls before the evidence:
• of striking variations in the integration of patient
values into our clinical behaviour
• of striking variations in the rates with which
clinicians provide interventions of established
benefit and uselessness to their patients.
• in the inability of clinicians to keep abreast of
important medical advances reported in primary
journals
Why do we need EBM?
 Daily need for valid information about
diagnosis, prognosis, therapy and
prevention
 approx twice for every three out patients or
may effect around eight decisions a day
Why do we need EBM?
 Traditional sources are usually inadequate
because
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out of date (textbooks)
frequently wrong (experts)
ineffective (didactic CME)
too overwhelming in volume and variable in
validity (medical journals)
Why do we need EBM? 3
 Disparity between our diagnostic skills and
clinical judgement which increase with
experience and our up to date knowledge
which declines
How do we practice EBM?
 STEP 1
• Converting the need for information (about
prevention, diagnosis, pregnosis, therapy,
causation etc) into an answerable clinical
question
How do we practice EBM?
 STEP 2
• track down the best evidence with which to
answer that question
 STEP 3
• critically appraise the evidence for its validity
(closeness to the truth), impact (size of effect),
and applicability (usefulness in our clinical
practice)
How do we practice EBM?
 STEP 4
• integrate the critical appraisal with our
patient’s unique biology , values and
circumstances
 STEP 5
• evaluate our effectiveness and efficiency in
executing steps 1-4 and seek ways to improve
them for next time
Can we do this?
 “Promoting and improving access to
summaries of evidence, rather than
teaching all GPs literature searching and
critical appraisal, would be the more
appropriate method of encouraging
evidence based general practice”
 Conclusion of survey into GPs attitudes to
EBM and there related educational needs
(BMJ 1996)
Can we do this?
 In other words miss out the appraising
(step 3) and just do the searching using
reliable sources or preappraised evidence
eg
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Cochrane
Best Evidence
Bandolier
York Centre
etc
Teaching EBM - opportunities
 Almost every patient!
 Problem and Random cases
 Topic tutorials
 Project
 Consultation skills (patients individual
circumstances ideas etc, giving
information, informed choice)