If we did not respect the evidence, we would have very little leverage in our quest for the truth'

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• If we did not respect the evidence, we would
  have very little leverage in our quest for the
  truth.
• Carl Sagan

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Getting the EvidenceAn introduction to
Evidence-Based Public Health

• Fall 2007
• Erika L. Sevetson, MS
• Ebling Library, UW Madison

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Session Objectives

• Learn the definition of EBPH
• Introduction to the process of EBPH
• Learn steps to finding the evidence

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Definition Evidence-based Public Health

• the development, implementation, and evaluation
  of effective programs and policies in public
  health through application of principles of
  scientific reasoning, including systematic uses
  of data and information systems, and appropriate
  use of behavioral science theory and program
  planning models
• Source Brownson, R.C. et al, Evidence-based
  public health, Oxford University Press, 2003.

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Community Needs Values
Scientific Evidence
Resources
EBPH
(adapted and modified from Muir Gray)
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Key Differences between EBM and EBPH
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Why is EBPH important?

• Provides assurance that decision making is based
  on scientific evidence and effective practices
• Helps ensure the retrieval of up-to-date and
  reliable information about what works and doesnt
  work for a particular public health question
• Provides assurance that ones time is being used
  most efficiently and productively in reviewing
  the best of the best information available on
  the particular public health question

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Why is EBPH important?

• During the past century, average life expectancy
  increased by approximately 30 years in
  industrialized countries
• Only about 5 years of that improvement is
  attributable to preventive services and medical
  care
• - Bunker et. al. 1994

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Some Key Characteristics of EBPH

• Intervention approaches developed based on the
  best possible scientific information
• Theory and systematic planning approaches are
  followed
• Problem solving is multi-disciplinary
• Sound evaluation principles are followed
• Results are disseminated to others who need to
  know and take action

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Advantages to Using EBPH

• Higher likelihood of success
• A move away from decision-making that relies too
  heavily on
• History
• Anecdotes
• Pressure from policy makers
• Identify common indicators
• Defend/expand an existing program
• Advocate for new programs
• New knowledge is generated to help others

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When is EBPH used?

• when its important to have scientific evidence
  to support decision making
• when evaluating the effectiveness and cost
  benefits of health programs
• when establishing new health programs
• when policies are being implemented
• when conducting literature reviews for grant
  projects.

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Steps in the EBPH Process

• 1) Formulating a clear question from a public
  health problem
• 2) Searching the literature
• 3) Appraising the evidence
• 4) Selecting the best evidence for a public
  health decision
• 5) Linking evidence with public health
  experience, knowledge, practice, and the
  communitys values and preferences
• 6) Implementing findings in public health
  practice and programs
• 7) Evaluating results.
• Source Jenicek, Milos and Sylvie Stachenko.
  2003. Evidence-based public health, community
  medicine, preventive care. Medical Science
  Monitor 9(2) p, SR2.

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Evidence-Based Public Health
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Steps in Searching the Public Health Literature

• Determine the public health problem and define
  the question
• Select information sources
• Identify key concept and terms
• Conduct the search
• Select documents for review
• Abstract relevant information from the
  documentation
• Summarize and apply the literature review

Source Adapted from Brownson. Evidence-based
public health. Oxford University Press, 2003, p.
128.
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Step 1 Determine/Define the question (Evidence
types)

• Type 1 Something should be done
• Type 2 This should be done
• Type 3 How the intervention should be done

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Step 1 Determine/Define the question

• P Patient/Population/Problem
• I Intervention/Item of interest
• C Comparison
• O Outcome

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A Scenario
C no comparison/placebo

• You coordinate social activities for a few of the
  citys senior centers. The latest Behavioral Risk
  Factor Surveillance System (BRFSS) survey showed
  that seniors in your state are not participating
  in regular exercise or many other health
  promotion behaviors. Youve heard that physical
  activities for older adults can have a host of
  benefits, and would like to submit a grant to
  begin an exercise program. You must find
  literature supporting the effect of exercise
  programs in reducing injuries or decreasing risk
  of chronic disease in the elderly.

P
I
O
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PICO

• P inactive seniors
• I community exercise programs
• C no comparison
• O reduced injuries/chronic disease

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The question

• In inactive senior populations, are formal
  exercise programs effective in reducing injuries
  and chronic disease associated with the aging
  process?

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Step 2 Select information sources

• Systematic Reviews and Meta-analyses
• Practice Guidelines
• Journal Literature
• Best Practices

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Types Sources of Evidence

• Systematic Review critical assessment and
  evaluation of research that attempts to address a
  focused question using methods designed to reduce
  the likelihood of bias.
• Meta-Analysis overview that incorporates a
  quantitative strategy for combining the results
  of several studies into a single pooled or
  summary estimate.
• Source R.C. Brownson et al, Evidence-Based
  Public Health, Oxford Oxford University, 2003.

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Types Sources of Evidence

• Practice Guidelines systematically developed
  statements to assist practitioner and patient
  decisions about appropriate health care for
  specific clinical circumstances may be developed
  by government agencies, institutions, or by the
  convening of expert panels.
• Source R.C. Brownson et al, Evidence-Based
  Public Health, Oxford Oxford University, 2003.

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Types Sources of Evidence
Journal literature
Source Guide to Research Methods The Evidence
Pyramid lthttp//servers.medlib.hscbklyn.edu/ebm/2
100.htmgt.
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The best is the enemy of the good-Voltaire
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The problem of randomized trials and parachutes.

• The effectiveness of parachutes has not been
  subjected to rigorous evaluation by using
  randomised controlled trials. We think that
  everyone might benefit if the most radical
  protagonists of evidence based medicine organised
  and participated in a double blind, randomised,
  placebo controlled, crossover trial of the
  parachute.
• Smith and Pell, BMJ, 2004

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Types Sources of Evidence

• Best Practices Public health programs,
  interventions, and policies that through
  experience have been evaluated, shown to be
  successful, and have the potential to be adapted
  and transformed by others working in the same
  field.
• Lacks rigorous evaluation of a systematic review
  or meta-analysis
• Applied across a variety of public health areas
• Vary widely in scope, methods, and quality
• Expert opinion to systematic methods
• Some are very influential
• Best Practices for Comprehensive Tobacco Control
  Programs

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Evidence spectrum
Weak
Strong
Local needs assessment
Meta analysis/ Systematic review/ Evidence-based
guidelines
No evidence/ case reports
Best Practices
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Step 3 Identify key concept and terms

• In inactive senior populations, are formal
  exercise programs effective in reducing injuries
  and chronic disease associated with the aging
  process?

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Step 3 Identify key concepts and terms

• P inactive seniors
• I community exercise programs
• C no comparison
• O reduced injuries/chronic disease

P Seniors/senior citizens elderly aged
I exercise physical activity recreation program
development program evaluation effective programs
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Step 4 Searching the literature

• Best Evidence Resources
• http//ebling.library.wisc.edu/EBPH

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Cochrane Collaboration
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PubMed
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Partners in Information Access for the Public
Health Workforce
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NICHSR National Information Center on Health
Services Research Health Care Technology
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Step 7 Summarize and apply the literature
review

• Appraising the Evidence Evaluating the Results
• What type of study/evidence is it?
• What are the results?
• Are the results valid?
• Were all important outcomes considered?
• Was an explicit process used to ID evidence?
• Has the guideline been subjected to peer review
  and testing?
• Can the results be applied to my context?

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• Thank You
• Erika Sevetson
• esevetson_at_library.wisc.edu
• 608.262.9506
• http//ebling.library.wisc.edu/EBPH