Transcript Evidence-Based Medicine: What does it really mean?
Evidence-Based Medicine: What does it really mean?
Sports Medicine Rounds November 7, 2007
What is Evidence-Based Medicine?
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A Philosophical Framework?
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An Evolving Concept?
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A Method of Practice?
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A Quality Improvement Approach?
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A Teaching Tool?
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A Potentially Dangerous Thing if used Incorrectly?
ALL OF THE ABOVE
A New Concept?
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The concept of modifying clinical practice based on research results has been in place for hundreds, perhaps thousands of years
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In the 20 th century (1990’s+) it has evolved to impact almost all fields of healthcare and policy; a structured approach
Largely Developed by One Group
The specific methodologies used to determine “best evidence” were largely established by a research group led by David Sackett & Gordon Guyatt at McMaster U.
What is Evidence-Based Medicine?
“Evidence-based medicine is the conscientious, explicit, & judicious use of current best evidence in making decisions about the care of individual
patients
” David Sackett, 1996
What is Evidence-Based Medicine?
“The integration of best research evidence with clinical expertise & patient values” Sackett et al, 2000
Types of Evidence-Based Medicine
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Evidence-based guidelines (EBG): practice of EBM at the organizational, institutional, or group level (establishing guidelines, policy, regulations)
Types of Evidence-Based Medicine
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Evidence-based individual decision making (EBID): EBM as practiced by the individual healthcare provider in determining how to treat patients Some are suggesting we may be too EBM focused
Evidence-Based Medicine: A Process 1. Identify a patient-oriented/practice oriented problem that is of interest 2. Develop a specific clinical question that targets the problem 3. Review the available evidence 4. Appraise the evidence → Decision 5. Integrate the evidence into your practice 6. Assess your outcomes (if appropriate)
An Idealistic EBM Model
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Important not to confuse Levels of Evidence with Quality of Evidence or Importance
Study Design Should Match “?”
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RCT: Homogeneous patients randomized to intervention A or B & compare outcomes
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Longitudinal Cohort: Compare a group of people with a risk factor over time to see who develops a disease/injury;
prognosis
Study Design Should Match “?”
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Case-Control: People with condition are compared to those without on a set of variables to assess effect(s) or associations with variables; Diagnostic or descriptive
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Cross-sectional Survey: A sample from a population is assessed for a certain disease/finding and specific risk factors at that single point in time; descriptive
Systematic Reviews & Meta-analyses
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Systematic Review:
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Structured review of the literature
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Set inclusion & exclusion criteria
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Assess study design quality
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Assess methodological quality (rarely)
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Compile & summarize results
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Goal: determine what the current evidence is on a specific topic
Systematic Reviews & Meta-analyses
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Meta-Analysis:
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Also a structured review of the literature
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Set inclusion & exclusion criteria
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Assess study design quality
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Assess methodological quality (rarely)
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Perform statistics
on the integrated results of the grouped studies
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Goal: draw conclusions from the results of the analysis of the grouped data
Systematic Reviews
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Goal: Summaries of best evidence; information overload Top level of evidence; everyone doing them Most are fair in terms of value Over 1.3 Million listed in MEDLINE alone About 5000 on the knee alone Need to evaluate carefully
Systematic Review Killers
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Low level research / Lack of Research
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Heterogeneity of subject pools
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Heterogeneity of methodology
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Lack of detail prohibits comparison
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Authors are often knowledgeable on general topic & evaluating study design & sources of bias, but not intervention methods
Must be Savvy Consumers of the Scientific Literature
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Cannot just read abstract, conclusions, & look at figures
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Hypotheses, methods, & results are most important
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Design appropriate?
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Bias?
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Conclusion based on results & consistent with methods?
Things to Consider
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EBM is only as good as the data available
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A quality case-control study is more meaningful than a flawed RCT
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Thus, systematic reviews of RCTs are not necessarily best evidence
Final Thoughts
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Payers have also adopted this
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Lack of evidence is being equated with lack of benefit; this is not true (call for evidence)
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There are other clinical decision-making approaches
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There are highly reputed health care experts who are stark opponents to the EBM approach accepted by most
Patient-Based Outcomes Measures
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What do they tell us?
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Does the KOOS QOL tell us someone’s knee is healthy?
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Can it tell us how well someone is doing or does it simply tell us if there is noteworthy disability or not?
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Is the difference between an 80 & 88 on the score the same as 88 to 96?
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What is a good score? In a young athlete?