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Evidence-Based Public Health: Finding and Appraising

Relevant Resources

Medical Library Association

Continuing Education Course

May 21, 2004

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Course Objectives1. Understand the characteristics of evidence-

based public health.2. Be informed about the variety of resources

available for evidence-based health practice.3. Gain an awareness of tools available for

collection management. 4. Know how to respond to information

questions typical of those posed by public health workers, students and researchers, and know the types of resources available to help answer questions.

5. Identify types of evidence and methodologies for appraising the public health literature.

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Objective 1 Understand the characteristics of

evidence-based public health

• What is Evidence-Based Public Health (EBPH)?

• Why is EBPH important?

• How does public health practice relate medical practice?

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Example:

Injury Prevention

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Definition ofEvidence-Based Public Health

“the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of communities and populations in the domain of health protection, disease prevention, health maintenance and improvement.”

Source:Jenicek M. Epidemiology, evidenced-based medicine, and evidence-based public health. J Epidemiol. Dec 1997;7(4):187-197.

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Definition ofEvidence-Based Public Health, cont.

“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 RC, Gurney JG, Land GH. Evidence-based decision making in public health. J Public Health Manag Pract. Sep 1999;5(5):86-97.

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Evidence-Based Practice

• Requires integrating practitioner expertise with the best evidence from systematic research.

• Involves finding and selecting resources that are credible, relevant, and applicable to practice.

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Process of Evidence-Based Practice

1. Define the problem: convert information needs into focused questions.

2. Find the best evidence from the literature.3. Critically appraise the evidence for validity

and relevance.4. Apply the evidence to practice.5. Evaluate the results.

Adopted from:Sackett DL, Rosenberg WM. The need for evidence-based medicine. J R Soc Med. Nov 1995;88(11):620-624.Sibbald WJ. Some opinions on the future of evidence-based medicine. Crit Care Clin. 1998;14(3):549-558.

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Why Evidence-Based Practice?

• So much information, too little time

• Need high quality, filtered information to make informed decisions

• Value of scientific knowledge for decision making

• Decisions should not be based only on intuition, opinion or anecdotal information

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Need for Evidence-Based Public Health

• Government downsizing - limited resources

• Need to justify actions and demonstrate benefits of public health interventions

• Decisions often made by politicians with limited health backgrounds

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From Public Health Professionals:

“Some things have simply always been done a certain way – are common practice, but there is really no research to back it up.”

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From Public Health Professionals:

“I make a lot of decisions about how money is going to be spent, and I would like to always be able to back it up and say that this is proven, or evidence-based.”

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From Public Health Professionals:

“Politics always overlays decision-making on everything that is not evidence-based in the public health world. Everything we do is imbued with political priorities and funding decisions.”

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The Evidence-Based Movement

EBM → EBPH

How does public health relate to medicine?

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Public Health: Health of Populations

Medicine: Health of Individuals

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• Focus on populations

• Prevention & health promotion

• Environment & human behavior interventions

• Diverse workforce, variable education & certifications

• Social sciences integral; clinical sciences peripheral to education

• Observational studies: case- control & cohort studies

Public Health• Focus on individuals

• Diagnosis & treatment

• Clinical interventions

• Well-established profession, standardized education & certification

• Clinical sciences integral; social sciences less emphasized

• Experimental studies with control groups: RCTs.

Medicinevs.

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Interaction of Public Health & Medicine:• Medical Care Section of APHA• Medicine/Public Health Initiative• AAMC-CDC Cooperative Agreement• Collaboration on emerging health threats

– Bioterrorism (anthrax, 2001) – Emerging infections (SARS, 2003) – Surveillance Technology: ability to quickly

exchange information electronically• Managed care: What can we afford?

Public Health Medicine

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10 Essential Services of Public Health

Public Health Functions Project, U.S. Dept. of Health and Human Services

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Evidence-Based Public Health

Decisions for Public Health Practice• Interventions

• Programs• Policies

Social values,Politics,

Economics

$

Expertise,Knowledge

Best Evidencefrom

Research

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Objective 2Be informed about the variety of

resources available for evidence-based health practice

• What types of resources can be used to make evidence-based public health decisions?

• The classification of public health evidence: What are the knowledge domains of public health?

• What journal literature is associated with each public health knowledge domain?

• What bibliographic databases index public health information?

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Sources of “Evidence”• Journal literature• Books• Conference proceedings & abstracts• Dissertations & theses• Unpublished scientific papers• Government reports (federal, state and local)• Policy statements, laws & regulations• Surveillance data• Newsletters• Teleconferences & webcasts• Alert systems • Listservs• Internet sources• Expert opinion

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Evidence Pyramid

From: The Medical Research Library of Brooklyn, http://servers.medlib.hscbklyn.edu/ebm/2100.htm

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Models of Information:Sources of Evidence-Based Knowledge

1. Reports of Original Research

2. Summaries, Critiques and Commentaries

3. Systematic Reviews, Meta-Analyses, and Evidence-Based Guidelines

4. Comprehensive Knowledge Bases

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1. Reports of Original Research

• Journal articles• Book chapters• Reports (government & other sources)• Newsletter articles• Conference proceedings and abstracts• Bibliographic databases that cite the above• Filtered searches of bibliographic databases

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Original Research Article: Am J Public Health

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Healthy People 2010 Information Access Projecthttp://phpartners.org/hp

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2. Summaries, Critiques and Commentaries

• Narrative reviews and summaries of original studies

• Critiques of original studies

• Expert commentary based on original studies

• Structured abstracts of individual research articles

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3. Systematic Reviews, Meta-Analyses, and Evidence-Based Guidelines

• Systematic reviews with explicit criteria

• Meta-analyses of data from original studies

• Evidence-based guidelines based on original studies, systematic reviews, and meta-analyses

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Cochrane Review Abstract

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Full Cochrane Review (from Ovid by subscription)

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Summary of Findings

41Link from Guide to Community Preventive Services: American Journal of Preventive Medicine

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4. Comprehensive Knowledge Bases

• Searchable online textbooks with up-to-date information

• Collections of multiple online resources– Journal articles– E-textbook chapters– Guidelines– Recommendations– Patient handouts– Images– Multiple databases with integrated searching– Internet links to related sources

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Graphic from UpToDate: Chest X-ray of SARS patient

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The Classification of Public Health Evidence:

What are the Knowledge Domains of Public Health?

• The field of public health is very broad and diverse

• There are multiple disciplines (knowledge domains) within the field of public health

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The Public Health Workforce

• Epidemiologists• Statisticians• Environmental Engineers• Animal Control Officers• Sanitarians• Food Scientists• Industrial Hygienists• Health Care Administrators• Health Economists• Politicians

• Social Workers• Mental Health Workers• Substance Abuse

Counselors• Doctors• Nurses• Teachers• Disaster Relief Workers• Nutritionists• Lab Technicians

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Sources Used to Identify the Knowledge Domains of Public Health

• Public health accreditation criteria• Public health associations• Government health agencies• National health objectives• Public health occupational categories• Public health literature• Public health subject headings from

NLM and LOC

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• General Public Health• Epidemiology• Biostatistics• Vital Statistics & Surveillance• Environmental Health• Occupational Health• Health Services Administration• Social & Behavioral Sciences• Health Promotion & Education• Community Health• Maternal & Child Health

• Public Health Nursing• Disaster Control &

Emergency Services• Communicable Diseases• HIV/AIDS• Nutrition• Chronic Diseases • Public Health Laboratory

Sciences• Public Health Informatics• Global Health

Identified Knowledge DomainsPublic Health

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Sources Used to Identify Public Health Journals

1. CDC Information Center

2. Healthy People 2010 Information Access Project

3. Core Public Health Journal Project

4. ISI’s Journal Citation Reports

5. Public health subject experts

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Public Health Journal Collection

• Knowledge Domain

• Online Access

• Price

• Impact Factor

• Databases Indexed In

• Table of Contents Email Alerts

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Public Health Bibliographic Databases• CDC Information Center• Public health librarians• Abstracting and indexing services for

key public health journals• Journals and newsletters• E-mail listservs• Public health websites• Public health subject experts

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Public Health Bibliographic Databases

– Access free or by subscription only?

– Who produced the database?

– What topics are covered?

– What kinds of materials are indexed?

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Future Endeavors

• Continue to identify public health journals, databases and evidence-based resources

• Update lists with new information• Continue study of the information needs

and access preferences of public health practitioners

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The Project’s Website

http://library.umassmed.edu/ebpph