Evidence-Based Medicine: Promises and Problems

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Evidence-Based MedicinePromises and Problems

• Victor R. Fuchs
• Henry J. Kaiser Jr. Professor Emeritus
• Stanford University
• Nuffield Trust, London, 12 May 2003

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• Evidence-based medicine (EBM) is the
  integration of best research evidence with
  clinical expertise and patient values.
• David Sackett et al.
• Evidence-Based Medicine
• 2nd edition, 2000, p. 1

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Reasons for Expansion of EBM

• The Demand for EBM
• The complexity of modern medicine
• The high cost of modern medicine
• The Supply of EBM
• Innovations that reduce the cost of acquiring,
  storing, processing, and retrieving information
• Methodological and substantive advances in
  mathematics, statistics, and the behavioral
  sciences that have applications to medical care

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The Promises of EBM

• More effective, safer medical interventions
  resulting in better health outcomes for patients
• Greater uniformity in the quality of care
• A slower rate of growth of expenditures for
  medical care

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best research evidence

• What does best mean?
• Why only the best?
• Can the best be the enemy of the good?
• What kind of evidence is excluded by the
  adjective research?

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clinical expertise

• EBM does not eliminate the need for
• Noting signs and symptoms
• Taking a good history
• Interpreting results of tests
• Thinking analytically

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Physician reasoning

• It is neither necessary nor desirable to make
  every physician a decision analyst, but a
  reasonable objective would be to give physicians
  enough experience in quantitative reasoning that
  they will know how to solve simple problems
  themselves, when and how to consult an analyst,
  and how to interpret the advice.
• David
  Eddy, NEJM, 1982

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patient values

• Risk aversion
• Time preference
• Living arrangements
• Working arrangements
• Medical care vs. other goods and services
• Income?

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• All medical care that is effective should be
  free to all
• A.L. Cochrane, Effectiveness and Efficiency
  Random Reflections on Health Services, 1972
• Is this possible in 2003?

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• Although the average beliefs in a community
  are appropriate for deciding, for example,
  whether chemotherapy or surgery should be paid
  for with public funds, decisions for individual
  patients must reflect their own personal beliefs
  and preferences.
• Sackett, et al., EBM, 2nd
  ed., p. 180

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EBM and Expenditures on Medical Care

• Will EBM act as a brake on expenditures?
• Yes. It will reduce utilization of ineffective
  care.
• Yes. It will show that some relatively
  inexpensive interventions are as effective as
  more costly alternatives.
• No. It will show that some interventions are
  more effective than any alternative, albeit at
  great cost relative to their benefit.
• For EBM to realize its potential, it is necessary
  to integrate it with cost-benefit analysis.

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Summary

• EBM is a great advance over informal,
  non-quantitative approaches to clinical
  decisions.
• The complexity and high cost of modern medicine
  make EBM necessary. Innovations outside of
  medicine make it feasible.
• EBM should result in more effective, more
  uniform, and more efficient medical care.
• EBM is an adjunct, not a substitute for
  physicians who can diagnose accurately, access
  evidence efficiently, and think analytically.
• The integration of EBM with cost-benefit analysis
  poses a major challenge for health policy.