Evidence-Based Medicine: Tools, Techniques, Results Balakrishnan S

Evidence-Based Medicine: Tools, Techniques, Results

Balakrishnan S

Motivation: EBM “Successes”

• Theophylline and asthma– We were doing the wrong thing

• Littenberg, 1988

• Beta blockers and MIs– We weren’t doing the right thing

• Yusuf, 1987

Uses of “EBM”

• Use of empirically-verified treatments in the care of patients

• Incorporation of research results into the process of care

• Ability to critically appraise research results

What is Evidence-Based Medicine?

• “The integration of individual clinical expertise with the best available clinical evidence from systematic research.”

– David L Sackett, W Scott Richardson, William Rosenberg, R Brian Haynes Evidence Based Medicine--How to Practice and Teach EBM, 1996

» Various definitions

“Clinical Evidence”

• Clinical vs physiological outcome– E.g., Sleeplessness rather than O2 saturation

• Clinical outcomes: See Outcome Research Institute

• Effectiveness vs efficacy– In practice vs biology

• Effectiveness: See DARE

“Best Available Clinical Evidence”

• Therapy– Double-blind, placebo-controlled, randomized clinical

trial• Diagnosis

– Independent, blind comparison with a reference standard

• Prognosis– Representative and well-defined prospective cohort of

patients at a similar point in the course of disease

• See Centre for Health Evidence

Levels of Evidences• (I-1) a well done systematic review of 2 or more RCTs • (I-2) a RCT • (II-1) a cohort study• (II-2) a case-control study• (II-3) a dramatic uncontrolled experiment• (III) respected authorities, expert committees, etc.. • (IV) ...someone once told me....

– http://www.phru.org/casp/– See also AAFP

“Systematic Research”

• “Meta-analysis” • “Literature synthesis”

– From Michael Scriven

“Integration of Individual Clinical Expertise”

• Informal• Formal (Decision analysis)

Questions

ARIF

Centre for EBM: http://163.1.212.5/docs/focusquest.html

Questions: PICO

Search for the Best Evidence

• Review articles• Community/professional standards• Systematic reviews• Original results

What are the Sources of Good Evidence?

www.welch.jhu.edu

CochraneWebsite

TRIP Database

www.tripdatabase.com(75 resources…)

Website

Getting to PubMed

PubMed Response

PubMed Clinical Query

www4.ncbi.nlm.nih.gov/PubMed/

PubMed, Clinical Query, cont’d

Question

Context

Subject matter

Website

Click on “Details”--((("atrial fibrillation"[MeSH Terms] OR atrial fibrillation[Text Word]) AND (((randomized controlled trial[PTYP] OR "drug therapy"[Subheading]) OR "therapeutic use"[Subheading:noexp]) OR (((((((((((((((((((((((((((((((((((((((((((((((((((((random[WORD] OR randomaly[WORD]) OR randoman[WORD]) OR randomand[WORD]) OR randombred[WORD]) OR randombreds[WORD]) OR randomdigit[WORD]) OR randomdot[WORD]) OR randome[WORD]) OR randomed[WORD]) OR randomely[WORD]) OR randomer[WORD]) OR randomezed[WORD]) OR randomic[WORD]) OR randomicity[WORD]) OR randomil[WORD]) OR randomily[WORD]) OR randomingly[WORD]) OR randomisation[WORD]) OR randomisations[WORD]) OR randomise[WORD]) OR randomised[WORD]) OR randomisees[WORD]) OR randomisely[WORD]) OR randomises[WORD]) OR randomising[WORD]) OR randomisly[WORD]) OR randomiz[WORD]) OR randomizable[WORD]) OR randomizadely[WORD]) OR randomizado[WORD]) OR randomization[WORD]) OR randomizations[WORD]) OR randomize[WORD]) OR randomized[WORD]) OR randomizedly[WORD]) OR randomizely[WORD]) OR randomizer[WORD]) OR randomizes[WORD]) OR randomizing[WORD]) OR randomlike[WORD]) OR randomly[WORD]) OR randomlyselected[WORD]) OR randommess[WORD]) OR randommized[WORD]) OR randommobility[WORD]) OR randomnes[WORD]) OR randomness[WORD]) OR randomomized[WORD]) OR randoms[WORD]) OR randomsource[WORD]) OR randomyl[WORD]) OR randomyly[WORD]) OR randomzied[WORD]))) AND notpubref[sb])

Controlled Vocabulary for Subject Matter

UpToDateWebsite

CISMeF

www.chu-rouen.fr/cismef/

Website

Dynamic Meta-Searching

sumsearch.uthscsa.edu/searchform45.htm

Website

Clinically Appraised TopicWebsites

CAT Content

CAT Synthesis

Washington University: PedsCCM

pedsccm.wustl.edu/EBJ/EB_Resources.htmlpedsccm.wustl.edu/EBJ/EB_Resources.html

Website

Details• Therapy/prevention• Diagnostic test• Prognosis• Harm• CPG• Systematic review• Economic analysis• Outcomes research

www.med.ualberta.ca/ebm/ebm.htm

Website

TherapyWebsite

Apply the Evidence to the Individual

Evidence-Based MEDICINE

• Do you tell what you know?– Does the patient want to participate?

• What is the emotional impact of what you have to say?

• What is the meaning to the patient of this evidence?

Problems

• Should a 30-year-old woman with recurrent uncomplicated lower UTIs be advised to drink cranberry juice to prevent reinfection?

• For a 63 year old woman with Type 2 diabetes, is gabapentin superior to amitriptyline as first-line therapy for painful peripheral neuropathy?

Task

• Well formulated question?• Discuss sites to go…everyone takes one• Formulate the query• Report back to your group on your success• The whole group reports back at the and of 30

min

Gabapentin

• A. GABAPENTIN is a gamma-aminobutyric acid (GABA) analog currently indicated as adjunctive therapy in the treatment of partial seizures with and without secondary generalization.– Partial seizures; social phobia

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