Evidence-based medicine:a hands-on workshop
Presented by
Chris Maloney, MDDirector, Medical Student Education in PediatricsVenus Wilke, MDAssistant Clerkship Director for PediatricsUniversity of UtahSalt Lake City, Utah
Objectives and Priorities
• Pediatrics Topics Session 1 and 2– Formulate a clinical question relative to a
patient’s problem. Conduct an effective search of the medical literature. Critically read the pediatric literature and apply the information in developing a differential diagnosis, diagnostic plan, or management plan.
Evidence-based medicineDefined
David L. SacketEvidence-based Medicine
How to practice and teach EBM
The integration of best research evidence with clinical expertise and patient values
EBM: Defined
Best research evidence – clinically relevant research . . . intothe accuracy and precision of diagnostic tests, the power of prognostic markers, and the efficacy and safety oftherapeutic, rehabilitative and preventive regimens.
Clinical expertise – the ability to use clinical skills and pastexperience to rapidly identify each patient’s health stateand diagnosis, their individual risks and benefits ofpotential interventions.
Patient’s values – the unique preferences, concerns and expectationseach patient brings to a clinical encounter and which must beintegrated into clinical decisions if they are to serve the patient.
barriers between research and practice
30 kg of guidelines per family doctor per year
25000 biomedical journals in print
8000 articles published per day
95% of studies cannot reliably guide clinical decisions
slide 4.2
2001 Bazian Ltd
The steps toward the practice of EBM
Step 1: Converting the need for information to an answerable question.
Step 2: Tracking down the best evidence with which to answer the question.
Step 3: Critically appraising that evidence for its validity (closeness to the truth),impact (size of the effect), and applicability (usefulness in ourclinical practice).
Step 4: Integrating the critical appraisal with our clinical expertise and with our patients unique biology, values and circumstances.
Step 5: Evaluating our effectiveness and efficiency at achieving steps 1-4and seeking new ways to improve them both for next time.
How evidence changed clinical practice
31. Extracranial to intracranial vascular anastomosis for occlusive Cerebrovascular disease: experience in 110 patients. Surgery 1977; 82: 648-654.
32. Failure of extracranial-intracranial arterial bypass to reduce the risk of Ischemic stroke. Results of an international randomized trial. The EC/IC Bypass Study Group. New England Journal of Medicine 1985; 313: 1191 – 1200.
hierarchy of major study designs
systematic review of RCTs
RCT
cohort
case control
interventional
observational
validity2001 Bazian Ltd
slide 7.1
Formulating a Question:“Background Information”
Ask for general knowledge about a disorder
This question has 2 essential components
• A question root with a verb
(who, what, where, when, how or why)
• A disorder or an aspect of a disorder
Formulating a Question:“Foreground Information”
Ask for specific information about managing a
patient with a specific disorder
This question has 3 or 4 essential components
P – Patient/Population/Problem I – Intervention/ExposureC – Control/Comparison (if relevant)O – Outcome
Evidence-based Resources• ACP Journal Club -- http://www.acpjc.org/index.html
– articles report original studies and systematic reviews that warrant immediate attention by physicians attempting to keep pace with important advances in internal medicine
• Clinical Evidence -- http://www.clinicalevidence.org– from the BMJ Publishing Group; an international source of the
best available evidence for effective health care • Guidelines -- http://www.guidelines.gov
– a public resource for evidence-based clinical practice guidelines • Evidence-based Reviews http://www.ovid.com
– Contains ACP Evidence-based Medicine reviews and Cochrane Library databases
• Centre for EBM -- http://www.cebm.utoronto.ca – this website helps develop, disseminate, and evaluate resources
that can be used to practice and teach EBM
Major Electronic Resources(available from Eccles Library)
• Access Medicine– http://www.accessmedicine.com/ home.aspx– A collection of textbooks, hot topics and self-assessment
tools: Harrison’s, Goodman and Gilman, etc.
• Cochrane Library – http://www3.interscience.wiley.com/cgi-bin/mrwhome/
106568753/HOME– A database of systematic reviews and more
• DynaMed– http://www.dynamicmedical.com/– 1,800 clinical topic summaries; designed for use at point of
care, providing best available evidence; updated daily
Major Electronic Resources(available from Eccles Library)
• PubMed/MEDLINE with LinkOut– http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?holding=uutahlib– Buttons indicate if material is available in print or electronic formats
• STAT!Ref – ACP’s PIER– http://online.statref.com/Splash.aspx?SessionId=4C78EFPGJWMMVSYS
– Physicians' Information and Education Resource – Plus 23 other textbooks for background information
• UpToDate – http://www.utdol.com/enterprise.asp?bhcp=1– Author evaluated review of the best evidence
• FreeMedicalJournals– http://www.freemedicaljournals.com– Promoting free access to medical journals
One approach to critically selecting an article
1. What is the Authors reputation?
2. What is the Institutions reputation?
3. What is the Type of study? i.e RCT, review
4. What is the Population and how do they
compare with my situation?
5. Regardless of the outcome will it change
my practice?
6. What are the Methods?
7. What are the Results?
Group Exercise
1. Working in groups of 2 - 4
2. Identify a question
preferably a foreground question
3. Determine a search strategy
4. Perform the search and obtain an article
5. Critically review the article(s) using the
worksheets
6. Share your question, strategy and results
References
1. How to practice and teach EBM. Sackett DL, Straus SE, Richardson WS, Rosenberg W, and Haynes RB. Churchill Livingstone. Second Ed. 2000.
2. Users guide to the medical literature. A manual for evidence-Based clinical practice. Guyatt G and Rennie D. AMA Press. 2001.
Worksheets
http://www.med.ualberta.ca/ebm/ebm.htm