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.

Best researchevidence

Clinical judgmentand experience

Patient values

EBM

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

Foreground

Experience with the condition

A B C

Novice Expert

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

General areas covered today

Therapy

Harm/Etiology

Diagnosis

Prognosis

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