introduction to ebm
DESCRIPTION
IntroductionTRANSCRIPT
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1EVIDENCE BASED MEDICINE
NOEL L. ESPALLARDO, MD, MSc
Knowledge Deteriorates in Time
r = -0.54
p
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2Political Endorsement
GMA mulls sanctions vs drug companies
only . . . is producing low priced drugs and
only . . . is selling
them.
Philippine Star, Jul 22, 2002
Pharmaceutical Influence
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0 3 6 9 12 15 18 21 24 27 30 33 36 39 42
1ST COURSE2ND COURSE
Pharmaceutical Influence
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140
0 3 6 9 12 15 18 21 24 27 30 33 36 39 42
1ST COURSE2ND COURSE
Pharmaceutical Influence
0
20
40
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0 3 6 9 12 15 18 21 24 27 30 33 36 39 42
1ST COURSE2ND COURSEINVITATION
Prescribing Practice
Inappropriate prescription for cardiovascular diseases
was very high
Overutilized Drugs of Unproven Benefit
calcium channel blockers
anticholesterol drugs
antioxidants
Underutilized Drugs of Proven Benefit
Beta blockers and diuretics
aspirin
What is Evidence-based Medicine
Evidence-based medicine is the
conscientious, explicit and judicious use of
current best evidence in making decisions
about the care of individual patients.
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3Evidence-based Medicine
The practice of EBM requires the integration of
individual clinical setting and expertise
with the
best available external clinical evidence from
systematic research
and the
patients preference
Case Scenario
CriticalAppraisal
ClinicalQuestion
LiteratureSearch
EvaluateApplication
Apply Evidence
EBM CYCLE
A 72 year old female consulted in your
clinic for hypertension and elevated
cholesterol. During your discussion on
cardiac risks, she inquires about the need to
take an anti-cholesterol drug.
What advise will you give to her?
The PatientDecision Making
in the Old Paradigm
Pathophysiology Hypercholesterolemia promotes coronary artery
disease thus cholesterol is a risk factor
Common sense Lowering cholesterol also lowers the risk of
coronary artery disease
Experience If cholesterol is elevated by laboratory
examination, it can be lowered by drugs
Experts National Cholesterol Education Program: screen
all adult patients and intervene when necessary
The EBFCP Practitioner
EBFCP practitioner
Among elderly patients who have elevated cholesterol will anti-cholesterol drug be
beneficial?
The search
MEDLINE
Randomized trial of cholesterol lowering in 4444 patients with coronary heart disease: the
Scandinavian Simvastatin Survival Study
Are the Results Valid
Was the assignment of patients to treatments randomized?
YES The title, abstract and the methodology section stated that the study was a double-blind randomized controlled trial
Were all patients who entered the trial properly accounted for and attributed at its conclusion?
YES 4,444 patients were randomized and analyzed according to intention-to-treat principle. In the table for the main analysis, the sum of patients in each group totaled 4,444, the number who were randomized
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4What are the Results
How large was the treatment effect?
Plac Tx
Mortality 12% 8% RR .70
RRR .30
ARR .04
NNT 25
How precise was the estimate of the treatment effect?
95% CI for relative risks of the different outcomes are less than 1
Can the Results Help Mein Caring for My Patient
Can the results be applied to my patient care?
YES Subjects included in this study were patients with angina or MI and elevated cholesterol
Were all clinically important outcomes considered?
YES The main outcomes considered were new onset
of MI, coronary death and overall cause of death
Are the likely treatment benefits worth the potential harm and cost?
NO The cost per life saved is 3.65 million
Alternative Use of P 3.65 M
For secondary prevention of death
with anti-cholesterol
drug
3.65 M per life saved
Other use of 3.65 M
7 coronary by-pass surgery
100 coronary revascularization (streptokinase) procedure in the ER including cost of ICU admission
A 72 year old female consulted in your
clinic for hypertension and elevated cholesterol.
During your discussion on cardiac risks, she
inquires about the need to take an anti-
cholesterol drug.
I would rather not give an anti-cholesterol
drug. The benefit is too small for the cost it will
take.
What Advice Will You Give to the 72 year old Woman
Avoid Nihilism EBFCP is Not About Statistics
Are you the doctor who
called my wife a
standard error ? ! ? #
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5RCT on Critical Appraisal Study Design, Setting and Subjects
Randomized controlled trial (cluster) Department of Family and Community Medicine Philippine
General Hospital
Medical interns
Outcomes Knowledge Practice (scores and conformance to recommendations)
history taking skills physical examination skills
diagnostic skills appropriateness of non-pharmacologic intervention appropriateness of pharmacologic intervention
Non-pharmacologic Intervention
EBM Workshop
Didactic Lecture
Linear Regression Adjusted f or Clusters and Baseline Skills (p < 0.001)
Mea
n Sc
ores
30
35
40
45
50
55
60
65
70
75
80
85
Baseline Af ter Intervention
EBM Workshop
Didactic Lecture
Linear Regression Adjusted f or Clusters and Baseline Skills (p = 0.113)
Mea
n Sc
ores
30
35
40
45
50
55
60
65
70
75
80
85
Baseline Af ter Intervention
Pharmacologic Intervention
EBM in Residency TrainingDFCM, U-PGH
EBFCP CONFERENCE (Thursdays 7-8)
Case presentation
Questions about history and physical examination
Diagnosis and differential diagnosis
Disposition
Formulate questions about the case
Assign a reporter and facilitator for the following Thursday (educational prescription)
EBM in Residency TrainingDFCM, U-PGH
EBFCP CONFERENCE (Thursdays 7-8)
Recall question
How the search was done
Appraisal of the searched article
Resolution of the problem
Can Appraisal of Guideline Improve Practice?
Appraisal of CPG at DFCM had mixed results
Before AfterDissemination
7%
30%
Before AfterDissemination
43%
32%
Appropriate Non-pharmacologic Treatment
Appropriate Pharmacologic Treatment
EBM and Quality of Care
% Improvement in Appropriateness
Feedback No Feedback
Diagnosis 0 0
History + 10 0
Physical Examination + 13 - 3
Endoscopy Request + 3 10
Treatment + 25 - 3
Follow-up Advice + 15 - 8
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6EBFCP ACTIVITIES
RELEVANCE TO RESIDENCY RELEVANCE TO FUTURE PRACTICE
BEFORE
AFTER p-value BEFORE AFTER p-value
Formulating question
36.54 37.50 .917 32.70 41.67 .038
Searching literature
37.57 36.39 .789 35.34 38.80 .436
Critical appraisal
37.46 36.50 .824 35.76 38.34 .573
Computation of stat
36.30 37.76 .754 36.72 37.30 .904
Applying to patients
35.71 38.40 .430 33.07 41.27 .044
Presenting 38.12 37.71 .624 39.00 34.83 .387
EBM Acceptability Survey EBM Program Evaluation Objectives
68% perceived that the objectives are attainable.
Relevance and effectiveness of the activities 100% perceived EBFCP-QA-Research activities as relevant 97% would advocate the use in patient care 82% believed that EBFCP-QA activities were adequately applied
in daily activities
Areas for improvement clarify objectives, emphasizing applicability in actual practice,
skills training, upgrading both the faculty skills and resource materials
Decision Making: Old Paradigm
Pathophysiologic understanding
Common sense
Experience
Experts
Others?
Pathophysiology and Common Sense is Not Enough
Plac Treat
Cholesterol 1.0 -9.0
Non-fatal MI 0.72 0.58
Total MI 0.89 0.74
Deaths 0.52 0.62
Experts Cannot Agree on Effectiveness of Treatment
1
3
5
7
9
0% 20% 40% 60% 80%
Experts vs. Evidence
Management of asthma in general practice
Steroids consider as first line maintenance
PEFR monitoring should be done
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7Experts vs. Evidence
Management of asthma in general practice
Steroids confer minimal benefit but significant increase in cost to asthma patients in general practice
PEFR monitoring is as good as symptom monitoring in general practice
Experts Are Not Up-to-date
1960
1965
1970
1975
1980
1985
1990
4
7
10
316
1783
2544
0.5 1.0 2.0
Favors Tx Favors Ctrl
Ro
uti
ne
Sp
ec
ific
Ra
re/N
ev
er
Ex
pe
rim
en
tal
No
t
Me
nti
on
ed
21
6
111281
2 6
5
10
878
124
3 1
1 23
2 65
3 143
11 265115 331117 392922 5452
23 5767
27 612530 634633 657143 2105954 2205165 4718567 4753167 48154 5
15
1 1 2
87
2
p < 0.01
p < 0.001
p < 0.0001
Decision Making in the New Paradigm
Pathophysiologic understanding
Common sense
Experience
Experts
Others?
Medical Evidence
Keep on Asking
Keep on Searching
Keep on Learning