September 16, 2010Larissa J. Lucas, MD

Senior Deputy Editor, DynaMed

DisclosureSenior Deputy Editor,

DynaMed, EBSCO Publishing, Ipswich, MAClinical Instructor in Medicine

Harvard Medical School, Boston, MA

Evidence Based Medicineconscientious, explicit, and judicious use of

current best evidence in making decisions about the care of individual patients

integrating individual clinical expertise with the best available external clinical evidence from systematic research

Sackett DL BMJ. 1996 Jan 13;312(7023):71-2

Clinical Expertise and Patient Preference

Haynes RB ACP J Club. 2002 Mar-Apr;136(2):A11-4.

Evidence Based Decision Making

Tilburt JC. J Eval Clin Pract. 2008 Oct;14(5):721-5

Why we need EBM toolsBarriers to answering clinical questions

Ebell MH. Am Fam Physician. 2009 Feb 15;79(4):293

TimeDoubtCultureAccess

Rising health care costsQuality of careIndustry sponsored studies (BMJ. 2007 Dec 8;335(7631):1202)

Answering clinical questions112 primary care

physicians3,511 visits with 635

questions22.8% questions were

investigated14% of questions

investigated not answered

time to answer questions 2 minutes during

consultation 32 minutes after

consultation

Ann Fam Med. 2007 Jul-Aug;5(4):345-52.

48 primary care physicians1,062 questions55% questions

investigateddoubt that answer

existed for 11% questions

resource failure in 26%41% of answers were

found easily31% found with difficulty

J Am Med Inform Assoc. 2005 Mar-Apr;12(2):217-24

How to ask a questionCochrane systematic

review4 trials

PICO training PubMed searching

training Information seeking

training Question formulation

training

Short-term benefitsImproved searching

timeImproved question

qualityImproved

satisfaction with searching

Increased correct answers

Cochrane Database Syst Rev. 2010 May 12;5:CD007335.

Existing toolsTextbooks and handbooksPubMedGuidelinesGoogleNews servicesSubscription online databases

Types of ToolsAlerting “foraging”

Prompts clinicians to ask questionsFiltered for relevance and validityTransparent evaluation and appraisal processEvidence ratingDifferentiate between “news” and practice

changing outcomesFinding “hunting”

Finding the answer to a clinical questionTransparent evidence rating criteriaTransparent reproducible methodologyEase of useEase of access

Relevance:Patient Oriented Outcomes

Symptoms Functioning Quality of Life Lifespan

Validity

ValidityUse of appropriate criteria for appraisal

Randomized trialsSystematic reviewsDiagnostic studiesPrognostic studies

Criteria include patient oriented outcomes

Highly Controlled ResearchRandomized Controlled TrialsSystematic Reviews

Physiologic ResearchPreliminary Clinical ResearchCase reportsObservational studies

Uncontrolled Observations

&Conjecture

Effect on Patient-Oriented OutcomesSymptoms (drivers license)Functioning (visual loss)Quality of Life (leg ulcers)Lifespan Effect on Disease MarkersDiabetes (Photocoagulation, GFR, NCV)Arthritis (x-ray, sed rate)Peptic Ulcer (endoscopic ulcer)Effect on Risk Factors for DiseaseImprovement in markers (blood pressure, HBA1C, cholesterol)

SORTA

Validity of Evidence

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SORTB

SORTC

Adapted with permission from Slawson D. Evidence Based Medicine: Don’t We Need Information Management Instead?Evidence Based Medicine: Don’t We Need Information Management Instead?

Defining Evidence-Based for a Clinical ReferenceEvidence-Based = conclusions based on best available evidence

1. Systematically identifying all applicable evidence

2. Systematically selecting the best available evidence from that identified

3. Systematically evaluating the selected evidence (critical appraisal)

4. Objectively reporting the relevant findings and quality of the evidence

5. Synthesizing multiple evidence reports

6. Deriving overall conclusions and recommendations from the evidence synthesis

7. Changing the conclusions when new evidence alters the best available evidence

What clinicians needComprehensive

Valid

Systematic

Current

Synthesized

AccessDesktopMobileElectronic Health

Record