Evidence-Based Medicine:introduction

Natapong Kosachunhanun, M.D.

My student are dismayed when I say to them.

” Half of what you are taught asmedical studentswill in1 0 yea rs have been shown to be wrong

. And the trouble is, none of you rteacher knows whi chhal f . ”

Dr. Sydney Burwell, Dean of Harva rdMedicalSchool,1 9 5 6

3

Rule 31 – Review the World Literature Fortnightly* *"Kill as Few Patients as Possible" - Oscar London

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If 80% achieved at each stage then0.8 x 0.8 x 0.8 x 0.8 x 0.8 x 0.8 x 0.8 = 0.21

What is evidence-based medicine?

“Evidence-based medicine is the integration of best research evidence with clinical expertise and patient values”

- Dave Sackett

Patient Concerns

Clinical Expertise

Best research evidence

EBM

Evidence based practice

Information “pull”Steps in EBM process

1. Formulate an answerable question

2. Track down the best evidence

3. Critically appraise the evidence

4. Integrate with clinical expertise and patient values

Good questions are the backbone of practicing EBM. It takes practice to ask the well-formulated question.

The nature of the question asked is critically experience dependent.

GENERAL KNOWLEDGE

SPECIFIC KNOWLEDGETYPE OF QUESTION

CLINICAL EXPERIENCE

What type of question you What type of question you are asking?are asking?

Clinical findingClinical finding DiagnosisDiagnosis PrognosisPrognosis TherapyTherapy PreventionPrevention

Sackett’s “Just in Time” learningAn EBM Approach to Education

Evidence cart on ward rounds - 1995 Looked up 2-3 questions per patient Took 15-90 seconds to find Change about 1/3 decisions Rounds took longer!

Dave Sackett

17

conclusion

Clinical decision should be based on best available scientific evidence, informed by epidemiological and biostatical reasoning.

Clinical problem should determine the evidence to be sought.

Conclusion from identified and critically appraised evidence must lead to changed patient management or health care decision.

Clinical performance should be constantly evaluated.

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