Evidence based medicine

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Evidence based medicine

• Learning and Teaching

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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).

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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.

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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 patients
  predicaments, rights, and preferences in making
  clinical decisions about their care.

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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.

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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

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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  rapidly out of date, to the detriment of patients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.

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What evidence-based medicine is

• this definition also helps us identify and
  understand what evidence-based medicine is not.

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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

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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

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Why do we need EBM?

• Traditional sources are usually inadequate
  because
• out of date (textbooks)
• frequently wrong (experts)
• ineffective (didactic CME)
• too overwhelming in volume and variable in
  validity (medical journals)

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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

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How do we practice EBM?

• STEP 1
• Converting the need for information (about
  prevention, diagnosis, pregnosis, therapy,
  causation etc) into an answerable clinical
  question

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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)

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How do we practice EBM?

• STEP 4
• integrate the critical appraisal with our
  patients 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

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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)

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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
• Cochrane
• Best Evidence
• Bandolier
• York Centre
• etc

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Teaching EBM - opportunities

• Almost every patient!
• Problem and Random cases
• Topic tutorials
• Project
• Consultation skills (patients individual
  circumstances ideas etc, giving information,
  informed choice)