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Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
Why bother with evidence-based practice?
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Why bother with evidence-based practice?

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An introduction to evidence-based medicine (EBM) with short section in history and why EBM? Then a brief overview of the 4 steps of EBM. …

An introduction to evidence-based medicine (EBM) with short section in history and why EBM? Then a brief overview of the 4 steps of EBM.
These slides have been used for starting a 1-day workshops in EBM

Published in: Health & Medicine, Education
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  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • Sackett DL, Rosenberg WMC, Gray JAM, Haynes RB, Richardson WS: Evidence based medicine: what it is and what it isn’t. BMJ 1996;312:71-2. This definition of what EBM is and isn’t has gained wide acceptance and made it easier for us to get our points across.
  • G:\CREBP\Training\EBM Workshops\Unnecessary Procedures.mp4 PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice An ideal information system would be able to answer – or tell us there is no answer – to any clinical question arising in practice. Studies of doctors and students performance on searching tasks suggest there is considerable room for improvement. Table 1 summarises 3 studies that assessed subjects answers both before and after searching. Overall answers improved but in 7 to 14% of cases answers went from right to wrong, that is, the search mislead subjects. And in 36 to 48% of cases wrong answers were not improved. The problem is one of both the information systems and the system user. Most clinicians are poorly trained in structuring questions and searching. An examination of the search terms used by the TRIP search engine showed most searches used a single term and rarely used explicit Boolean connectors.
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice An ideal information system would be able to answer – or tell us there is no answer – to any clinical question arising in practice. Studies of doctors and students performance on searching tasks suggest there is considerable room for improvement. Table 1 summarises 3 studies that assessed subjects answers both before and after searching. Overall answers improved but in 7 to 14% of cases answers went from right to wrong, that is, the search mislead subjects. And in 36 to 48% of cases wrong answers were not improved. The problem is one of both the information systems and the system user. Most clinicians are poorly trained in structuring questions and searching. An examination of the search terms used by the TRIP search engine showed most searches used a single term and rarely used explicit Boolean connectors.
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • PRESENTATION ONE 05/08/13 Introduction to Evidence-Based Practice
  • Transcript

    • 1. Why bother with Evidence-Based Practice? Professor Paul Glasziou Bond University www.crebp.net.au/ www.testingtreatments.org Free pdf: Ch 5, 6, 7
    • 2. Introductory Lecture: Objectives What is Evidence-Based Medicine? The steps of doing EBM 1. Formulate Clinical Questions 2. Search for Evidence 3. Appraisal of research 4. Apply to clinical problem
    • 3. 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 ResearchSackett DL, Rosenberg WMC, Gray JAM, Haynes RB, Richardson WS: Evidence based medicine: what it is and what it isn’t. BMJ 1996;312:71-2.
    • 4. “EBM” - birth of a term Update of CMAJ series on how to read a paper JAMA User guides 1991 authors seek a new term Clinical epidemiology? Scientific medicine? Evidence-based medicine!
    • 5. The need for Evidence Vertebroplasty for osteoporotic fractures Gray et al Spine 2008. Nation-wide and State-specific primary vertebroplasty rates per 100,000 Part B fee-for-service Steady rise in use of vertebroplasty for a decade 2009: two large trials publish showing no effect over placebo Slides courtesy R Buchbinder
    • 6. Unnecessary Procedures http://www.cbsnews.com/8301-18563_162-5217954.html Please click on the black screen to view the video
    • 7. that did not work  Vertebroplasty for osteoporotic fractures (NEJM, 2010)  Arthoscopic knee lavage (Moseley, NEJM, 2002)  Blood glucose monitoring for non-insulin dependent diabetes (DiGEM trial, BMJ 2007)  Tight control of diabetes (ACCORD, NEJM, 2010)  Prostate cancer screening (Djulbegovic, BMJ 2010)  Ovarian cancer screening (JAMA, 2011)
    • 8. Most medical innovations don’t work an analysis of 136 trials in myeloma New Treatment Better New Treatment Worse
    • 9. How can we find the research that will improve the care of our patients? 0 500000 1000000 1500000 2000000 2500000 Biomedical MEDLINE Trials Diagnostic? MedicalArticlesperYear 5,000? per day 1,500 per day 95 per day MedicalArticlesPerYear 19 of 20
    • 10. What should you believe?
    • 11. Keeping up to date What is your JASPA* score? * (Journal Associated Score of Personal Angst) J: Are you ambivalent about renewing your JOURNAL subscriptions? A: Do you feel ANGER towards prolific authors? S: Do you ever use journals to help you SLEEP? P: Are you surrounded by PILES of PERIODICALS? A: Do you feel ANXIOUS when journals arrive? *Modified from: BMJ 1995;311:1666-1668 0 (?liar) 1-3 (normal range) >3 (sick; at risk for polythenia gravis and related conditions)
    • 12. 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
    • 13. Part 2: 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
    • 14. Step 1 Formulate an answerable clinical question Structure of researchable questions – PICO-T  Population/Patients  Intervention  Comparison  Outcome  Time
    • 15. Formulating answerable clinical questions Structure of researchable questions – PICO-T  Population/Patients  Outcome
    • 16. What are your clinical questions?  A 35 year old man says his brother recently died of a ruptured cerebral aneurysm. He is worried about whether he might have one and what the chances are that it would rupture. -> PICO Table
    • 17. Risk Factors Cause(s) Symptoms Signs, Tests Prognosis Treatment Effect Past Current Future Types of question: stroke Frequency Cohort Study SurveyInception Cohort Study Treatments Randomised Trial CT Scan Cross Sectional Study
    • 18. What are the … outcomes (PO?) Outcomes ? Patients Qualitative Research
    • 19. The “best” evidence depends on the type of question Level Treatment Prognosis Diagnosis I II Randomised trial Inception Cohort Cross sectional III
    • 20. Level Treatment Prognosis Diagnosis I Systematic Review of … Systematic Review of … Systematic Review of … II Randomised trial Inception Cohort Cross sectional III The “best” evidence depends on the type of question
    • 21. What do you do about conflicting claims?
    • 22. 2. Searching: finding good answers?
    • 23. Impact of searching on correctness of answers to clinical questions Right to Right Wrong to Right Right to Wrong Wrong to Wrong McKibbon (GP or IM) 28% 13% 11% 48%
    • 24. Impact of searching on correctness of answers to clinical questions Right to Right Wrong to Right Right to Wrong Wrong to Wrong McKibbon (GP or IM) 28% 13% 11% 48% Quick Clinical (GPs) 21% 32% 7% 40% Hersh (Med students) 20% 31% 12% 36% Hersh (Nursing) 18% 17% 14% 52%
    • 25. 3. Rapid Critical Appraisal It’s peer-reviewed, therefore it must be OK?
    • 26. Is the PICO a POEM? Patient Oriented Evidence that Matters
    • 27. Critical Appraisal Steps Did you find good quality studies? Two steps 1.What is the PICO (Question) 2.Is the potential bias low? • “RAMMbo” (Valid Study?) • “FAITH” (Valid Review?)
    • 28. Use the RAMMbo to check validity Was the Study valid? 1. Representativeness  Who did the subjects represent? 1. Allocation  Was the assignment to treatments randomised? 1. Maintainence  Were the groups treated equally? 1. Measurements blinded OR objective  Were patients and clinicians “blinded” to treatment? OR  Were measurements objective & standardised? Modified from: User Guide. JAMA, 1993
    • 29. Fundamental Equation of Error  Measure = Truth + Bias + Random Error Use good study design Use large numbers Researcher Critically Appraise Design Confidence Intervals and P-values Reader
    • 30. Two methods of assessing the role of chance  P-values (Hypothesis Testing)  use statistical test to examine the ‘null’ hypothesis  associated with “p values” - if p<0.05 then result is statistically significant  Confidence Intervals (Estimation)  estimates the range of values that is likely to include the true value Relationship between p-values and confidence intervals - if the value corresponding to ‘no effect’ (RR of 1 or treatment difference of 0) falls outside the CI then the result is statistically significant
    • 31. Step 4: Applying to the individual  What do the results mean on average?  What do they mean for this individual?
    • 32. Applying research requires both “Whether to” and “How to”  “Whether to”  Evidence quality  Individual applicability  “How to”  What & where?  How long & how often? BMJ 2003; 327 : 135

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