1EVIDENCE BASED MEDICINE

NOEL L. ESPALLARDO, MD, MSc

Knowledge Deteriorates in Time

r = -0.54

p

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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1ST COURSE2ND COURSE

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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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.

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

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 ? ! ? #

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

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

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5

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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

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

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Ra

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ev

er

Ex

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tal

No

t

Me

nti

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21

6

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2 6

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3 1

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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