Understanding concepts of Evidenced Based Medicine
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Transcript of Understanding concepts of Evidenced Based Medicine
Understanding concepts of Understanding concepts of Evidenced Based MedicineEvidenced Based Medicine
Frank J. Domino, M.D.Frank J. Domino, M.D.
ProfessorProfessor
University of Massachusetts Medical University of Massachusetts Medical SchoolSchool
Learning ObjectivesLearning Objectives by the end of the session, you will by the end of the session, you will
Appreciate the basic statistical concepts Appreciate the basic statistical concepts involved in EBM involved in EBM
Contrast absolute risk reduction (ARR) Contrast absolute risk reduction (ARR) with relative risk reduction (RRR) and with relative risk reduction (RRR) and
Calculate the number needed treat (NNT); Calculate the number needed treat (NNT); and and
Understand how sometimes statistical Understand how sometimes statistical interpretation can leads us astray….interpretation can leads us astray….
Outline of TalkOutline of Talk
1.1. Types of Papers in the Medical LiteratureTypes of Papers in the Medical Literature1.1. Review vs. Systematic ReviewReview vs. Systematic Review
2.2. RCT, Cohort, Case-Control StudiesRCT, Cohort, Case-Control Studies
3.3. BiasBias
2.2. Statistics: AR, RR, RRR, NNTStatistics: AR, RR, RRR, NNT
3.3. Patient vs Disease Oriented EvidencePatient vs Disease Oriented Evidence
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What is Evidence-Based Medicine?What is Evidence-Based Medicine?
Integration ofIntegration of
• Best research evidence Best research evidence (from Systematic (from Systematic Reviews)Reviews)
• Clinical expertiseClinical expertise
• Patient valuesPatient values
Patient Oriented Outcomes [POEPatient Oriented Outcomes [POE] ] vs Disease/Intermetdiate Outcomes vs Disease/Intermetdiate Outcomes [DOE][DOE]
Sacket et al “How to Teach and Practice EBM”, Churchill Livingston, 2000 Len
Patient
Values
Types of Research Types of Research InformationInformation
Review ArticlesReview Articles
VsVs
Systematic ReviewsSystematic Reviews
Traditional Review ArticleTraditional Review Article - - Summary of the literatureSummary of the literature
Often valuable reviews Often valuable reviews
for medical practicefor medical practice
Problems:Problems: Do not Do not necessarilynecessarily include all relevant include all relevant
evidenceevidence Author bias mixed with the evidenceAuthor bias mixed with the evidence Publisher’s motives in ?Publisher’s motives in ?
A A Systematic ReviewSystematic Review Article Article– – Utilizes quality standards to judge the literatureUtilizes quality standards to judge the literature
Clear objective for evaluation of studyClear objective for evaluation of study Identify studies (Identify studies (Randomized Controlled Randomized Controlled
TrialsTrials) meeting review criteria ) meeting review criteria The results of acceptable studies combinedThe results of acceptable studies combined Outcome of those studies publishedOutcome of those studies published If Quantitative, combined -> Meta AnalysisIf Quantitative, combined -> Meta Analysis
Systematic ReviewSystematic Review
Systematic ReviewMeta Analysis
Antibiotics and Acute SinusitisAntibiotics and Acute SinusitisA Cochrane A Cochrane SystematicSystematic Review Review
www.cochrane.orgwww.cochrane.org
1. Objectives:1. Objectives: ‘To determine whether ‘To determine whether antibiotics are indicated for acute sinusitis, antibiotics are indicated for acute sinusitis, and if so, which antibiotic classes are most and if so, which antibiotic classes are most effective.’effective.’
2. Search strategy:2. Search strategy: Studies identified via Studies identified via searches of MEDLINE & EMABASE, contacts searches of MEDLINE & EMABASE, contacts w/ pharmaceutical companies and w/ pharmaceutical companies and bibliographies of included studies.bibliographies of included studies.
3. Selection criteria 3. Selection criteria
Randomized controlled trials n Randomized controlled trials n >> 30 adults. 30 adults. Compare antibiotic to control or other Abx.Compare antibiotic to control or other Abx. DX confirmed by radiograph or aspiration. DX confirmed by radiograph or aspiration. Outcomes: cure or symptom improvement.Outcomes: cure or symptom improvement.
Of Of 20582058 potentially relevant studies, potentially relevant studies, onlyonly 49 stu49 studies (13,660 pts) met review criteria! dies (13,660 pts) met review criteria!
> 2000 of questionable significance……..> 2000 of questionable significance……..
4. Data Combined 4. Data Combined Reviewers' conclusions:Reviewers' conclusions:
• For acute maxillary sinusitis, current For acute maxillary sinusitis, current evidence is evidence is limitedlimited but supports penicillin but supports penicillin or amoxicillin for 7 to 14 days. or amoxicillin for 7 to 14 days.
• Clinicians should weigh the moderate Clinicians should weigh the moderate benefits of antibiotic treatment against benefits of antibiotic treatment against the potential for adverse effects.the potential for adverse effects.
The Cochrane Library,The Cochrane Library, Oxford Oxford
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The Forest PlotThe Forest Plot
Estimate and confidence interval for each study
Estimate and confidence for the meta-analysis
Direction of effect
Scale (effect measure)
Line of no effect
Estimates with 95% confidence intervals
0.2 1.0 5
Favours LR Favours control
Risk ratio
Kennedy 1997
Locke 1952A
Lopes 1997
Reynolds 1998
Seiberth 1994
Forest Plot: If <> to your Left, Intervention was Effective at Lowering Risk of Outcome.
Len
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Interpreting a Meta Analysis using a Forest Plot
Len
Study DesignsStudy Designs
The Systematic Reviews use:The Systematic Reviews use:
1. Randomized Controlled Trials1. Randomized Controlled Trials
Other Study types: Other Study types:
2. Cohort Studies2. Cohort Studies
3. Case Control Studies3. Case Control Studies
Randomized Controlled Clinical TrialsRandomized Controlled Clinical Trials
A population is chosen, then randomly A population is chosen, then randomly assigned to an intervention or notassigned to an intervention or not
An An interventionintervention is given to the is given to the study study population.population.
The Non-InterventionThe Non-Intervention group group receives a receives a placebo or some standard of care.placebo or some standard of care.
Differences in pre identified outcomes are Differences in pre identified outcomes are measured and produce measured and produce
ABSOLUTE RISK of those outcomesABSOLUTE RISK of those outcomes
Randomized Controlled Trials Randomized Controlled Trials Bias in the Medical LiteratureBias in the Medical Literature
Attrition bias – Attrition bias – how were “drop outs” how were “drop outs” accounted foraccounted for
Publication biasPublication bias – only positive results get – only positive results get publishedpublished
Comparator bias Comparator bias - new Tx compared to - new Tx compared to placebo rather than current standardplacebo rather than current standard
Commercial BiasCommercial Bias – who funded the study – who funded the study and what motivated the researchersand what motivated the researchers
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Attrition BiasAttrition Bias
What happened to What happened to everyoneeveryone who who was randomized?was randomized?
Was the study “Intention to Treat”?Was the study “Intention to Treat”?
May need to review the data to May need to review the data to determine if they “add up”determine if they “add up”
Bob
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Publication BiasPublication BiasFactors that prevent publicationFactors that prevent publication40% of All RCT not published40% of All RCT not published
RCT of using 400 IU/day of Vitamin E to RCT of using 400 IU/day of Vitamin E to prevent Coronary Artery Diseaseprevent Coronary Artery Disease. .
InterventionIntervention PlaceboPlacebo
MIMI 4.24.2 3.9 3.9 p=0.7p=0.7
No benefit to supplementing diet with No benefit to supplementing diet with Vitamin E in the prevention of CADVitamin E in the prevention of CAD
Bob
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Comparator BiasComparator BiasComparing new treatment to no treatment, Comparing new treatment to no treatment,
rather than the current standard of carerather than the current standard of care
““Azithromycin is superior to Azithromycin is superior to placebo in the treatment of placebo in the treatment of Acute Sinusitis”Acute Sinusitis”
That is nice, but is it superior That is nice, but is it superior to Amoxicillin? Don’t know; to Amoxicillin? Don’t know; they didn’t do (or won’t they didn’t do (or won’t publish) that study.publish) that study.
Bob
Commercial BiasCommercial Bias
Look for Disclosures of Look for Disclosures of the Authors the Authors
Who funded the studyWho funded the study Bottom of The Front Bottom of The Front
page and page and just before Reference Sectionjust before Reference Section
Ex. JUPITER StudyEx. JUPITER Study
20BIAS: Assume it is Present Bob
P < 0.001
Statistically significant!
AR MI placebo - 0.76%AR MI Crestor - 0.35%
Cohort StudiesCohort Studies
Prospective, ObservationalProspective, Observational studies with conclusions studies with conclusions
Produces aProduces a Relative Risk (Relative Risk (RRRR))RR=Incidence of disease in RR=Incidence of disease in ExposedExposed
divided by Incidence of disease in divided by Incidence of disease in Unexposed Unexposed populationpopulation
Ex: Framingham Heart studyEx: Framingham Heart study
Relative Risk (Relative Risk (RRRR))
If If < 1.0< 1.0, risk is REDUCED, risk is REDUCED
If If > 1.0> 1.0, risk is INCREASED, risk is INCREASED
RR = Number of times more or less than 1 an event will happen in one group when compared to another
““The RR of death if involved in The RR of death if involved in an MVA without a seat belt = an MVA without a seat belt =
3.5”3.5”
“Tea drinkers have a 0.6 RR of dying from CAD”
CorrelationCorrelationdoes not does not prove prove cause and effect!cause and effect!
Does tea Does tea drinking drinking prevent prevent CAD???CAD???
Vitamin E & CADVitamin E & CAD3 3 cohort studiescohort studies mid-90’s concluded mid-90’s concluded vitamin E use vitamin E use correlatedcorrelated with a lower with a lower
risk risk for CAD. for CAD.
1.1. Antioxidant Vitamins and Coronary Heart Antioxidant Vitamins and Coronary Heart DiseaseDisease
2.2. Vitamin E Consumption and Risk of Coronary Vitamin E Consumption and Risk of Coronary Disease in MenDisease in Men
3.3. Vitamin E Consumption and Risk of CAD in Vitamin E Consumption and Risk of CAD in WomenWomen
The Heart Outcomes PreventionThe Heart Outcomes PreventionEvaluation (HOPE) Study Evaluation (HOPE) Study
2000:2000: Controlled TrialControlled Trial of Vitamin E for 5 Yr of Vitamin E for 5 Yr::
rates of MI, CVA & CV death did not differ rates of MI, CVA & CV death did not differ significantly from placebo (16.2% v 15.5 %).significantly from placebo (16.2% v 15.5 %).
•HOPE II (JAMA 2005) Long-term use of vit E in HOPE II (JAMA 2005) Long-term use of vit E in CHD or DM patients does not prevent cancer or CHD or DM patients does not prevent cancer or major cardiovascular events major cardiovascular events and may increase and may increase
the risk for HFthe risk for HF
Case Control StudiesCase Control Studies
Identify a Potential trend in diseaseIdentify a Potential trend in disease Collect exposure history of “CASES”Collect exposure history of “CASES” Identify similar people age/gender Identify similar people age/gender
like Cases but without diseaselike Cases but without disease Compare Cases to Controls to Compare Cases to Controls to
determine if exposure increased determine if exposure increased ODDS of disease.ODDS of disease.
Ex: Cigarette smokingEx: Cigarette smoking
Outline of TalkOutline of Talk
1.1. Types of Papers in the Medical LiteratureTypes of Papers in the Medical Literature1.1. Review vs. Systematic ReviewReview vs. Systematic Review
2.2. RCT, Cohort, Case-Control StudiesRCT, Cohort, Case-Control Studies
3.3. BiasBias
2.2. Statistics: AR, RR, RRR, NNTStatistics: AR, RR, RRR, NNT
1.1. Patient vs Disease Oriented EvidencePatient vs Disease Oriented Evidence
Which drug would you take?Which drug would you take?
Drug A Drug A can reduce your MI risk by 1/3can reduce your MI risk by 1/3 Drug B Drug B can reduce your MI risk by 9 %can reduce your MI risk by 9 % Drug C Drug C every 11 patients who take every 11 patients who take
Drug C, one MI will be preventedDrug C, one MI will be prevented
A B C
The Scandinavian Simvastatin Survival The Scandinavian Simvastatin Survival Study (4S)Study (4S)
4444 pts with angina or previous MI and ↑ 4444 pts with angina or previous MI and ↑ cholesterolcholesterol
Randomized to simvastatin or placebo. Randomized to simvastatin or placebo. After 5 yrs, simvastatin reduced TC 25%, After 5 yrs, simvastatin reduced TC 25%,
LDL 35% and increased HDL 8%. [DOE]LDL 35% and increased HDL 8%. [DOE]
MI or death:MI or death:
622(622(28%)28%) control group (p control group (placebo)lacebo)
431pts431pts (19%) simvastatin group [POE] (19%) simvastatin group [POE]
Disease Oriented vs. Patient Oriented Disease Oriented vs. Patient Oriented EvidenceEvidence
DOEDOE
Lidocaine Lidocaine ↓ ↓ V. Tach V. Tach
HRT will HRT will ↓↓ LDL; LDL;
↑↑ HDLHDL
Fluoride Fluoride ↑↑ bone bone densitydensity
POEPOEProphylactic Lido Prophylactic Lido ↑↑ CV CV
deathdeath
Increased risk of stroke Increased risk of stroke & Mortality& Mortality
Does not prevent Does not prevent fracturesfractures
Absolute Risk Reduction (Absolute Risk Reduction (ARRARR))
4S Trial: The 4S Trial: The differencedifference between the between the incidence of outcome in the incidence of outcome in the controcontrol l
group (28%) and the incidence in the group (28%) and the incidence in the treatment group (19%). treatment group (19%).
ARRARR = Incid Control – Incid Treatment = Incid Control – Incid Treatment
28%- 19% = 9% ARR28%- 19% = 9% ARR
Relative Risk ReductionRelative Risk Reduction
Absolute Risk Reduction (ARR) Absolute Risk Reduction (ARR) divided by divided by
Incidence in the control groupIncidence in the control group
RRRRRR = (28-19)/28 = 33% = (28-19)/28 = 33%
RRR is not the same as AR or RRRRR is not the same as AR or RR
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Relative Risk ReductionRelative Risk Reduction
A way to describe (and often over A way to describe (and often over inflate) the relative impact of a inflate) the relative impact of a treatment on an outcometreatment on an outcome
Bob
Number Needed to Treat (NNT)Number Needed to Treat (NNT)
NNT NNT - the number of people needed to - the number of people needed to receive an intervention before one person receive an intervention before one person gets the expected outcome!gets the expected outcome!
NNT = 100 divided by NNT = 100 divided by Absolute Risk Absolute Risk ReductionReduction..
NNT NNT = 100/(28-19) = 11= 100/(28-19) = 11
11 pts w/ CAD need to be treated with 11 pts w/ CAD need to be treated with simvastatin to prevent 1 from having a simvastatin to prevent 1 from having a subsequent MI or death.subsequent MI or death.
Which drug would you take?Which drug would you take?
Drug A Drug A can reduce your MI risk by 1/3can reduce your MI risk by 1/3rdrd
• Relative Risk Reduction (Relative Risk Reduction (RRR =RRR = 33%) 33%)
Drug B Drug B can reduce your MI risk by 9%can reduce your MI risk by 9%• Absolute Risk Reduction (Absolute Risk Reduction (ARRARR = 9 %) = 9 %)
Drug C Drug C prevent an MI for every 11 prevent an MI for every 11 patients who take it regularlypatients who take it regularly• Number Needed to Treat (Number Needed to Treat (NNTNNT = 11) = 11)
Another example of NNT:Another example of NNT:Does alendronate prevent hip fractures in Does alendronate prevent hip fractures in
postmenopausal women ?postmenopausal women ?
The published study:The published study: Low bone mass densityLow bone mass density One or more fractures at baselineOne or more fractures at baseline Alendronate 5 mg/d x 24 mo, then Alendronate 5 mg/d x 24 mo, then
10mg/d10mg/d Outcome - subsequent hip fracturesOutcome - subsequent hip fractures
OutcomesOutcomes
P < 0.044 P < 0.044 Statistically Statistically
significant!significant!
Statistical Significant does NOT equal Clinical Significant
Statistical SignificanceStatistical Significance
An indication that the findings are An indication that the findings are not not due to chance!due to chance!
P < 0.05 means there is < 5% chance P < 0.05 means there is < 5% chance the difference between the placebo the difference between the placebo and treated group is a chance and treated group is a chance occurrence.occurrence.
It is It is not annot an implication of implication of clinicalclinical meaning (significance).meaning (significance).
A Closer Look…A Closer Look…
Hip fracture rate in Hip fracture rate in treated group - 1%treated group - 1%
Hip fracture rate in control group - 2.2%
Absolute Risk ReductionAbsolute Risk Reduction
Placebo incidence – Treated incidencePlacebo incidence – Treated incidence
2.2% - 1% = 1.2%2.2% - 1% = 1.2%
A A high riskhigh risk patient can reduce patient can reduce her risk of a hip fracture by her risk of a hip fracture by
1.2% from alendronate x 4 yrs 1.2% from alendronate x 4 yrs
What happens to the other 82 women?What happens to the other 82 women?
They receive the medication, They receive the medication, incurring the cost of treatment along incurring the cost of treatment along with the exposure to the potential with the exposure to the potential side effects, but…..side effects, but…..
obtained obtained nono identified identified benefit!benefit!
What is this 56% ???What is this 56% ???
RelativeRelative Risk Risk Reduction Reduction
2.2-1(ARR)/2.2 = 56%2.2-1(ARR)/2.2 = 56%
Number Needed to TreatNumber Needed to Treat
100/ARR = 100/(2.2-1) = 83100/ARR = 100/(2.2-1) = 83
83 83 high riskhigh risk women would have women would have to be treated with alendronate to be treated with alendronate for 3 years to prevent one for 3 years to prevent one additional hip fractureadditional hip fracture
Evidence-Based MedicineEvidence-Based Medicine
What’s a What’s a “good”“good” NNT ? NNT ?
Depends on Depends on risksrisks of intervention vs of intervention vs outcomeoutcome
The best NNT would be 1 - every The best NNT would be 1 - every treated patient benefited, but no treated patient benefited, but no placebo benefitplacebo benefit
NNTs NNTs << 5 indicate very effective 5 indicate very effective treatmentstreatments
Good NNTGood NNT NNT is a VALUE BASED decisionNNT is a VALUE BASED decision NNTs of 50 or 100 useful for NNTs of 50 or 100 useful for
interventions to reduce death after interventions to reduce death after heart attack.heart attack.
NNS in the 1000’s as screened NNS in the 1000’s as screened population includes those with and population includes those with and without disease.without disease.
Decisions should also consider costs Decisions should also consider costs and risk of the intervention (NNH)and risk of the intervention (NNH)
Some NNTsSome NNTsPrevent 1Prevent 1 DrugDrug NNTNNT
MI/DeathMI/Death ASA X 1 yearASA X 1 year 500 healthy 500 healthy ♂♂
Stroke/MI/DeathStroke/MI/Death
DeathDeath
Acute Rheumatic Acute Rheumatic feverfever
Hip FxHip Fx
25 unstable angina
15 severe HTNAnti-HTN X 1yrAnti-HTN X 1yr
ACEiACEi
PenicillinPenicillin
Ca/Vit D X 3yrCa/Vit D X 3yr
700 mild HTN 700 mild HTN
18 CHF/post-MI18 CHF/post-MI
3500 strep throats3500 strep throats
30 ambulatory30 ambulatory♀♀
Number Needed to Harm?Number Needed to Harm?
DrugDrug NNTNNT NNHNNH
Prevent 1 Hip FxPrevent 1 Hip Fx
HRT X 5yrsHRT X 5yrs
333 333 ♀♀
Cause 1 StrokeCause 1 Stroke 250 ♀250 ♀
Cause 1 Breast CaCause 1 Breast Ca 200 ♀200 ♀
Cause 1 DVTCause 1 DVT 100 ♀100 ♀
OM pain reliefOM pain relief
Antibiotic X Antibiotic X 10 days10 days
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Cause VomitingCause Vomiting 1212
Cause DiarrheaCause Diarrhea 1212
Cause a RashCause a Rash 1212
Crestor for Low Risk PatientsCrestor for Low Risk Patients
AR MI with placebo - 0.76%AR MI with placebo - 0.76%
AR MI with Crestor - AR MI with Crestor - 0.35%0.35%
ARR = 0.76-0.35 =0.41%ARR = 0.76-0.35 =0.41%
RRR= 0.41/0.76 = 54%RRR= 0.41/0.76 = 54%
NNT = 100/0.41 = 244 NNT = 100/0.41 = 244
244 low risk patients would have to be 244 low risk patients would have to be treated with rosuvastatin for 2 years to treated with rosuvastatin for 2 years to prevent one MIprevent one MI
What happens to the other 243 What happens to the other 243 patients?patients?
They receive the medication, They receive the medication, incurring the cost of treatment along incurring the cost of treatment along with the exposure to the potential with the exposure to the potential side effects, but…..side effects, but…..
obtained obtained nono recognized recognized benefit!benefit!
Solving Questions on the Fly:Solving Questions on the Fly:Using Best EvidenceUsing Best Evidence
Frank J. Domino, M.D.Frank J. Domino, M.D.
ProfessorProfessor
Dept. Family Medicine & Community Dept. Family Medicine & Community HealthHealth
University of Massachusetts Medical University of Massachusetts Medical SchoolSchool
Worcester, MassachusettsWorcester, Massachusetts
[email protected]@umassmemorial.org
5555
Objectives:Objectives:
1.1. Understand what characteristics Understand what characteristics denote “Best” medical evidencedenote “Best” medical evidence
2.2. Appreciate spectrum of resources Appreciate spectrum of resources available to use at bedside or with available to use at bedside or with E.M.R.E.M.R.
3.3. Solve your questions in real timeSolve your questions in real time
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Why this session?Why this session?
President Obama January 2009:President Obama January 2009: Provision of $40,000 in incentives Provision of $40,000 in incentives
(beginning in 2011) for physicians to (beginning in 2011) for physicians to use an EHRuse an EHR
Funds to coordinate interoperable EHRs Funds to coordinate interoperable EHRs Education programs to train in EHR useEducation programs to train in EHR use Creation of HIT grant and loan programs Creation of HIT grant and loan programs Acceleration of the construction of the Acceleration of the construction of the
National Health Information Network (NHIN) National Health Information Network (NHIN)
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Who has an E.H.R.?Who has an E.H.R.?
http://www.aafp.org/fpm/2009/1100/10.html
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Now that Patient Information is at Now that Patient Information is at the bedside, why not solve the bedside, why not solve
questions there too?questions there too?
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1. Screening: 1. Screening: 56 year old male wants to know 56 year old male wants to know why there is a controversy about why there is a controversy about
Prostate Cancer screening; Prostate Cancer screening; “if “if you find it early, won’t I stand a you find it early, won’t I stand a better chance of living longer?”better chance of living longer?”
For Questions about SCREENING, For Questions about SCREENING, use:use:
www.ahrq.gov www.ahrq.gov
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Prevention: www.ahrq.govPrevention: www.ahrq.gov
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2. Basics:2. Basics:You have a MS III in your office who sees a You have a MS III in your office who sees a
patient w/ patient w/ Irritable Bowel SyndromeIrritable Bowel Syndrome & & wants to learn about this Diagnosiswants to learn about this Diagnosis
www.emedicine.com www.emedicine.com freefree www.epocrates.com free/$www.epocrates.com free/$ www.5mcc.com $www.5mcc.com $
NotNot: Google or Wikipedia: Google or Wikipedia
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OR, go to: www.emedicine.com
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7070Epocrates: www.epocrates.com
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Continuing Med. Ed.Continuing Med. Ed.
““Listen to Lecture”Listen to Lecture”
+: “hit PLAY”+: “hit PLAY”
-: Industry Funded/Biased, Boring-: Industry Funded/Biased, Boring
Point of Care (tracks usage)Point of Care (tracks usage)
+: Fills YOUR Knowledge Gaps, +: Fills YOUR Knowledge Gaps, rewards your desire to improverewards your desire to improve
UpToDate, 5 Minute CC, DynamedUpToDate, 5 Minute CC, Dynamed
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3. Deeper Dive3. Deeper Dive 79 y/o becomes acutely ill after his 79 y/o becomes acutely ill after his
most recent intra-vesicle BCG most recent intra-vesicle BCG instillation for Transitional Cell Ca of instillation for Transitional Cell Ca of
Bladder; what should you do?Bladder; what should you do?
www.uptodate.com $www.uptodate.com $
www.accessmedicine.com www.accessmedicine.com (Harrison’s) $(Harrison’s) $
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7474150 Hits
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4. Best Evidence4. Best Evidence
You are frustrated about the controversy You are frustrated about the controversy re: serum homocysteine levels in re: serum homocysteine levels in
patients at risk for CHD and you want patients at risk for CHD and you want the the
BEST EVIDENCEBEST EVIDENCE..
Systematic Review DatabasesSystematic Review Databases• Cochrane Database of Systematic ReviewsCochrane Database of Systematic Reviews• Others from PUBMED.GOVOthers from PUBMED.GOV
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What is What is Evidence Based Practice?Evidence Based Practice?
Integration ofIntegration of
• Best research evidenceBest research evidence
• Clinical expertiseClinical expertise
• Patient valuesPatient values
Most Explicit: Use a Systematic Review Most Explicit: Use a Systematic Review to guide Patient Careto guide Patient Care
Sacket et al “How to Teach and Practice EBM”, Churchill Livingston, 2000
www.pubmed.gov
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www.pubmed.govwww.pubmed.gov
Use Clinical Queries FilterUse Clinical Queries Filter Search suffixesSearch suffixes * adds any suffix to the end of the * adds any suffix to the end of the
word (ie. asthm*)word (ie. asthm*) [ti] = any term in the title [ti] = any term in the title
(ie. Asthm*[ti])(ie. Asthm*[ti]) [ab] = any term in abstract[ab] = any term in abstract
(ie. Asthm*[ab](ie. Asthm*[ab]
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Online & Electronic ToolsOnline & Electronic ToolsCost/Yr Pros Cons
SCREENING:
www.ahrq.gov
$0.00 -Free
-Unbiased
-Standard of Care
- Too many “I” ratings
BASICS:
www.emedicine.com
$0.00 Free
-Current
-Lots of ads, now owned by Medscape
-May become biased based upon funders
-PDA version weak
BASICS::
www.epocrates.com
$195.00 -Rx, Basics, DDX, Lab, calculators, Pt Ed
-Not Biased
-PDA & Web
-Web not done yet
BASICS::
www.5mcc.com
$99.00 -Rx, Basics, DDX, Lab, Video, Calculators, Patient Education
-One fee Book, PDA, Web
-no CME yet
Deeper Dive
www.uptodate.com
$500-1st Yr
$400
-Comprehensive Medicine content
Subspecialist Author
-PDA, CME
-can be overwhelming
-PDA version HUGE
Deeper Dive www.accessmedicine.com/harrisons
$200/yr Adult Medicine -have to buy subscriptions to other resources, which adds up quickly
BEST EVIDENCE
www.pubmed.gov
Free Use Clinical Queries filter Not all reviews listed are systematic reviews, read carefully
Solving Questions on the Fly:Solving Questions on the Fly:Using Best EvidenceUsing Best Evidence
Frank J. Domino, M.D.Frank J. Domino, M.D.
ProfessorProfessor
Dept. Family Medicine & Community HealthDept. Family Medicine & Community Health
University of Massachusetts Medical SchoolUniversity of Massachusetts Medical School
Worcester, MassachusettsWorcester, Massachusetts
[email protected]@umassmemorial.org
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Let’s look for answers to your Let’s look for answers to your questionsquestions