Introduction to Evidence Based Medicine

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Introduction to Evidence Based Medicine
Dr. Tina Dewi Judistiani, dr. SpOG Dept
Epidemiology and Biostatistics School of
Medicine Universitas Padjadjaran
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KEY REFERENCES

• Greenberg RS, Daniels SR, Flanders D, Elley
  JW, Boring JR. Medical Epidemiology. 1st ed.
  Prentice-Hall International Inc. London .1993
• West S. Basic Public Health Concepts What
  is Screening? Wilmer Eye Institute - Johns
  Hopkins University. Available from
  www.crag.uab.edu/safemobility/Screening.ppt
• Coggon D, Rose J, Barker DJP. Epidemiology
  for the uninitiated. Available from
  http//resources.bmj.com/bmj/readers/readers/epide
  miology-for-the-uninitiated/10-screening
• Loong TW. Understanding sensitivity and
  specificity with the right side of the brain.
  BMJ 2003 327 716-19.
• Sedlmeier P and Gigerenzer G. Teaching
  Bayesian reasoning in less than two hours.
  Journal of Experimental Psychology General. 130
  (3)380-400, 2001.
• Glaziou , P. Centre of Evidence Based Medicine,
  Oxford.

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I am here to learn EBM because .

1. I have no idea
2. I will be a practicing doctor
3. I will be working on researches
4. I will help others use evidence
5. I plan to teach EBM

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Life long learning

• The hardest conviction to get into the mind of a
  beginner is that the education upon which he is
  engaged is not a medical course, but a life
  course.
• For which the work of a few years under teachers
  is preparation.

Sir William Osler (1849-1919), from The Student
of MedicinePaul Glasziou , Centre for
Evidence-Based Medicine University of Oxford
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What kind of doctor would you become ?
Smart young doctor
William Osler, 1900
Paul Glasziou , Centre for Evidence-Based
Medicine University of Oxford
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Do you want to get there ?
Wise experienced smart young doctor
Paul Glasziou , Centre for Evidence-Based
Medicine University of Oxford
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How is the construction building of Learning
EBM like ?
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EBM learning

1. What is Evidence-based practice?
2. Asking well-formulated Questions
3. Searching for evidence
4. Critical Appraisal
5. Diagnostic studies
6. Intervention studies
7. Prognostic studies

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Introductory Lecture Objectives

• 1. What
• What is evidence-based medicine?
• What does it look like in practice?
• 2. How
• Formulate Clinical Questions
• Search for Evidence
• Appraisal of research
• Apply to clinical problem

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What is evidence-based medicine?

• Evidence-based medicine is the integration of
  best research evidence available with clinical
  expertise and patient values - Dave
  Sackett

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Rule 31 Review the World Literature
Fortnightly "Kill as Few Patients as Possible"
- Oscar London
Medical Articles Per Year
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Is keeping up to date Mission Impossible?
Bluegreenblog 2006
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Coping with the overload three possible things
you might try
A. Read an evidence-based abstraction
journal (and cancel other journals)
B. Keep a logbook of your own clinical
questions C. Run a case-discussion journal
club with your practice
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A. Filtered knowledge How much is valid AND
relevant?

• PROCESS
• 140 journals scanned
• 60,000 articles
• Is it valid? (lt5)
• Intervention RCT
• Prognosis inception cohort
• Etc
• Is it relevant?
• 6-12 GPs specialists askedRelevant?
  Newsworthy?
• lt 0.5 selected

www.evidence-basedmedicine.com
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B. Recognize important knowledge gaps

• Keep a logbook of questions
• Answer a few important questions
• Discuss evidence with colleagues (journal club)

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C. Run and EBM journal club
H

• Example Questions
• Are antidepressants safe in adolescents?
• Is atenolol OK for hypertension?
• Should all diabetics take aspirin?
• Do probiotics prevent AB diarrhoea?
• Does bibliotherapy help depression?
• What is the impact of Tamiflu on flu?
• Are combined inhalers better in asthma?
• Bold from EBM journal

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Reminding The 4 steps of pull EBM

1. Formulate an answerable question
2. Track down the best evidence
3. Critically appraise the evidence
4. Individualise, based clinical expertise and
   patient concerns

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Case-based health care problems

• Write down one problem from the case
• What were the critical questions?

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Step 1Formulate an answerable clinical
question

• Structure of researchable questions PICO-T
• Population/Patients
• Intervention
• Comparison
• Outcome
• Time

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What are your clinical questions?

• A 35 year old man says his brother recently died
  of an acute myocardial infarction He is worried
  about whether he might have one and what the
  chances are that it would happen to him

-gt PICO Table
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Types of question stroke
Cohort Study

Inception Cohort Study
Survey
Frequency
Prognosis
Risk Factors
ECG Angiography MRI
Degenerative process in the Coronary artery
Treatments Randomised Trial
Treatment Effect
Symptoms Signs, Tests
Cause(s)
Cross Sectional Study
Past current
future
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Question Structure PICO
Patients
Page 24
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How common is CAD ?
Figure for illustration only, does not reflect
actual prevalence
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Risk Factors Do patients with obesity have
higher mortality?
Patients
Predictors, Risk Factors, tests
Page 24
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Treatment Do patients with familial history
benefit from regular exercise and diet
modification ?
Patients
Page 24
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The best evidence depends on the type of
clinical question

• What are the phenomena/thoughts?
• Observation cross sectional studies
• What is frequency of the problem?
• prevalence frequency cross sectional
  studies
• Does this disease correlated to certain risk
  factors ?
• odds ratio case control studies
• 4. Who will get the problem?
• relative risk - inception cohort
• Different question for diagnostic studies and
  therapetic studies .

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2. Searching finding good answers?
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Searching made easy ?
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3. Rapid Critical Appraisal

• Its peer-reviewed, therefore it must be OK?

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USE THE TOOLS WORKSHEET FOR EACH STUDY TYPES
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Step 4 Applying to the individual

• What do the results mean on average?
• What do they mean for this individual?