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Evidence-Based Public Health: Finding and Appraising

Relevant Resources

Medical Library Association

Continuing Education Course

April 27, 2006

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Objectives

• Understand the characteristics of evidence-based public health

• Be informed about the variety of resources available

• Know how to respond to typical questions posed by public health workers and what resources are available to provide info

• Identify types of evidence and methods for appraising the public health literature

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Overview

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

• Why is EBPH important?

• What is the difference between public health practice & medical practice?

• What can be used as evidence for making informed public health decisions?

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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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Evidence-Based Practice

• Requires integrating practitioner expertise with the best evidence from systematic research. [someone must be doing research]

• Involves finding and selecting resources that are credible, relevant, and applicable to practice. [how unique is your community?]

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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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Evidence for Public Health Practice and Policy Decisions

• “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.”

Politicians need evidence to make decisions about public health programs.

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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.”

“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.”

Quotes on this and previous page from MA DOH, Bureau of Communicable Dis Control

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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.

Medicine

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Interaction of Public Health & Medicine:• Medicine/Public Health Initiative• AAMC-CDC Cooperative Agreement (pop health)• 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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Sources of Public Health Evidence

• Journal literature• Books• Conference

proceedings & abstracts

• Dissertations & theses• Unpublished scientific

papers• Government reports• Policy statements, laws

& regulations

• Surveillance data• Newsletters• Teleconferences &

webcasts• Alert systems • Email discussion lists• Internet sources• Expert knowledge &

opinion

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Evidence Pyramid

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

Applicable to toxicology, environmental health, food safety, vaccine development, etc…

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RCTs

Cohort Studies

Case-Control Studies

Descriptive Studies,Case Series & Reports

Ideas, Editorials, Opinions

Systematic Reviews & Meta-analyses

[Perhaps also Meta-syntheses of qualitative studies?]

Evidence Pyramid

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

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Evidence Matrix

Research Question

Qualitative Research

Survey Cross-Sectional

Case-control Studies

Cohort Studies

Quasi- Experimental Studies

Non Experimental Evaluations RCTs

Systematic Reviews

Effectiveness

Process of Service Delivery

Salience

Safety

Acceptability

Cost Effectiveness

Appropriateness

Satisfaction with the Service

Petticrew M, Roberts H. Journal of Epidemiology and Community Health, 2003

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The Project’s Website

http://library.umassmed.edu/ebpph

Evidence-Based Practice for Public Health ProjectUniversity of Massachusetts Medical School 22

CDC/ATPM Qualitative StudyInvestigation of Information Needs of

Public Health Professionals

Nancy La Pelle, PhD

Roger L. Luckmann, MD, MPH

E. Hatheway Simpson, MPH

Elaine R. Martin, DA

Identifying Strategies to Improve Access to Credible and Relevant Information for Public

Health Professionals: A Qualitative Study

2006

Evidence-Based Practice for Public Health ProjectUniversity of Massachusetts Medical School 23

Findings from Study of Public Health Workforce Information Needs

There are many relevant websites to search: need for one portal access.

Bombarded with unfiltered, irrelevant information: need filtered searches.

Too little information on legislation and policy change and newly identified health threats.

Evidence-Based Practice for Public Health ProjectUniversity of Massachusetts Medical School 24

Findings Continued

Need information from areas beyond biomedical domains.

Need access to systematic reviews and summary information.

Need access to full-text journal articles, government reports (grey literature), and conference proceedings.

Need for training in accessing evidence-based resources.

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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. 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• Dissertations from Schools of Public Health• 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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2. Summaries, Critiques and Commentaries

• Summaries of original studies• Critiques of original studies• Expert commentary and

recommendations based on original studies

• Structured abstracts of individual research articles

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http://www.medscape.com/publichealth

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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

• NB: Not all guidelines are EB; some are expert opinion/consensus

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33Link from Guide to Community Preventive Services: American Journal of Preventive Medicine

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4. 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– Data (prevalence, incidence, costs, charges, etc..)– Multiple databases with integrated searching

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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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Public Health is Multidisciplinary

• 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• Librarians• Communication• Security & Enforcement /

Health Police

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Defining 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 the

National Library of Medicine

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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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Define the public health problem

Convert the information needs into focused questions

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Forming a Searchable Public Health Question

PICO

P - Population

I - Intervention

C - Comparison

O - Outcome

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Search and find the best evidence

Critically appraise the evidence for validity and relevance

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Sample Search Pathway1. Evidence-Based Guidelines

2. Systematic Reviews

3. Pre-formulated Searches

4. Best and Model Practices

5. Bibliographic Databases

6. Public Health Journals

7. Health Data and Statistics

8. Legislation and Policy

9. Government Reports

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EBPPH Project Web Site: http://library.umassmed.edu/ebpph

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Evidence-Based Resources for Public Health Practice

1. Evidence-Based Guidelines

2. Systematic Reviews

3. Pre-formulated Searches

4. Best & Model Practices

5. Public Health Bibliographic Databases

6. Public Health Journals

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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 discussion lists• 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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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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Continuing the Pathway:Evidence-Based Resources for

Public Health Practice

7. Health Data and Statistics 8. Legislation and Policy9. Government Reports

Public Heath Web Portal: http://PHPartners.org

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Public Health Web Portal: http://PHPartners.org

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EBPH Critical Appraisal and Database Searching

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Brainstorming – “Best Practices”

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EBPH Searching

• Findings from attendees of 2004 EBPH course at MLA:– MEDLINE – every six months (12)– Cochrane – never (3) < 6 mon (2) >6 mon (7)– ERIC – never (1) < 6 mon (7) > 6 mon (4)– NCJRS - never (9) < 6 mon (3) > 6 mon (0)– TOXNET - never (3) < 6 mon (6) > 6 mon (3)– PIE - never (11) < 6 mon (1) > 6 mon (0)– AGELINE - never (3) < 6 mon (8) > 6 mon (1)– POPLINE - never (5) < 6 mon (4) > 6 mon (2)– AGRICOLA - never (3) < 6 mon (6) > 6 mon (3)

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Forming a searchable public health question

• The PICO framework used in evidence-based medicine can also be used to create a searchable question in public health.

• P Patient, population, problem• I Intervention (program or treatment or

screening test or exposure or prognostic factor)

• C Comparison (if any)• O Outcome

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PICO Exercise• You coordinate social activities for a few of the

city’s 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. You’ve heard that physical activities for older adults can have a host of benefits, but there aren’t many resources with which to build a program. You must find literature supporting the effect of exercise in reducing injuries or decreasing risk of chronic disease in the elderly. Increasing client satisfaction and social engagement are secondary goals.

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Searchable Foreground ?

• Using the PICO to create a searchable question along the lines of the following:

• In the Patient Population with this Problem, does the Intervention more than the Comparison (if any) result in the Outcomes.

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Issues in PH Searching

• Access– Free versus paid– Functionality

• Vocabulary– The language of public health– Built-in or external thesauri

• Levels of Available Evidence

• Keeping Up

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Critical Appraisal

• Does this item address the question? [Are the population and intervention similar enough to be useful]

• Is this item quality evidence?

• Always better to appraise full-text• Realistically, most make the first cut by

appraising the abstract (or executive summary)

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MEDLINE / PubMed

• Access (free): http://www.pubmed.gov

• Also available through multiple vendors

• Coverage: 1950 – present (moving backwards as well) ; journal and newsletter literature

• 4300+ journals in biomedical science, nursing, allied health, psychology, etc..

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MEDLINE Sample Search

• Are needle exchange programs effective for reducing HIV transmission in intravenous drug users? What are the characteristics of successful programs.

• MeSH

– Needle-Exchange Programs

– HIV Infections/transmission or /prevention & control

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MEDLINE Results• Clinical Queries – Systematic Reviews

– Evaluating effectiveness of syringe exchange programmes: current issues and future prospects. Soc Sci Med. 2000 Dec.

• Combine subject terms with cohort studies– Continued transmission of hepatitis B and C viruses, but no

transmission of human immunodeficiency virus among intravenous drug users participating in a syringe/needle exchange program. Scand J Infect Dis. 2000

– High rates of HIV infection among injection drug users participating in needle exchange programs in Montreal: results of a cohort study. Am J Epidemiol. 1997 Dec [debated]

– Effectiveness of needle-exchange programmes for prevention of HIV infection. Lancet. 1997 Jun 21

• Other studies use statistical modeling; program evaluation; qualitative research – interviews.

• Are they interested in other intermediate outcomes such as risk reduction?

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Cochrane Library

• Access to Cochrane Database of Systematic Reviews:– http://www.thecochranelibrary.com (Free to search

and get abstract; pay for full-text review– Also indexed in PubMed and available for purchase

through OVID

• Coverage: – Brings together a number of regularly updated (every

3 months) evidence-based medicine databases, some available free at http://www.crd.york.ac.uk/crdweb/

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Cochrane Search Sample

• Is pneumococcal vaccination effective in reducing the number of ear infections in children? Is it worthwhile to promote it for otherwise healthy children in your community?

• Search Terms (Keywords or MeSH)– Pneumococcal Vaccines– Otitis Media /prevention & control– Age group (children) – since this is a small database

you might be willing to leave out the age group and just browse.

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Cochrane Results

• Straetemans M, Sanders EA, et al. Pneumococcal vaccines for preventing otitis media. Cochrane Database Syst Rev. 2002;(2):CD001480.

• Document Delivery: – If you do not have full-text access to this

database, you can order the full-text of a Cochrane review through the Cochrane website for a fee.

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ERIC (Educational Resources Information Center)

• Access (free) – http://www.eric.ed.gov/– Also available through multiple vendors

• Coverage:– The database contains more than 1 million

abstracts of education-related documents and journal articles from 1966 onwards.

– Linked full-text to grey literature (reports, documents, etc…)

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ERIC Search Sample

• The school health program at your health department and the board of education are interested in making sure that kids with asthma are appropriately treated while at school. What are issues about access to a child’s school health records that need to be addressed in your plan to develop electronic school health records?

• Search terms (ERIC descriptors or identifiers) – Browse or search the Thesaurus of ERIC Descriptors at– http://www.ericfacility.net/extra/pub/thessearch.cfm– Confidential Records– School Health Services– Student Records

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ERIC Results• School Health Services and Educational Records:

Conflicts in the Law. Gelfman, Mary H. B.;Schwab, Nadine C. West's Education Law Reporter v64 n2 p319-28 Jan 31 1991

• A Computerized School Health Records System: Problems and Prospects Pitkin, Olive;Rosner, Lester J. Journal of School Health v41 n5 p258-261 May 1971

• Document Delivery – ERIC Document Retrieval Service – direct ordering or through

OCLC. Libraries and research institutions can offer their patrons access to full-text copies of ERIC documents online through E*Subscribe.

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National Criminal Justice Reference Service Abstracts & Full-Text

• Access (free) http://abstractsdb.ncjrs.org/content/AbstractsDB_Search.asp – Also available through multiple vendors

• Coverage– National Criminal Justice Reference Service Abstracts

Database contains summaries of more than 180,000 criminal justice publications from 1970 to the present. The Full-Text Virtual Library contains 7,000+ full-text publications.

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NCJRS Search Sample• Your maternal, child and reproductive health program has been invited to

review the case management of pregnant inmates at a state correctional facility. You are looking for current practices with pregnant inmates to compare with best practices for prenatal care in the community health center environment.

• Search Terms – National Criminal Justice Thesaurus – You can browse or search it at

the Advanced Thesaurus Search Screen http://www.ncjrs.gov/abstractdb/thesaurus/search.asp

– Pregnant inmates – Pregnant offenders – Pregnant women– Use above as keywords– Prenatal care

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NCJRS Results

• Pregnant Girls and Moms in Detention. Justice Policy Journal: Analyzing Criminal and Juvenile Justice Issues and Policies Volume:1 Issue:2 Dated:Spring 2003 Pages:3 to 20

• Nine Months to Life - The Law and the Pregnant Inmate. Journal of Family Law Volume:20 Issue:3 Dated:(1981-1982) Pages:523-543– [note that this does not have the subject headings above

assigned, but comes up in a keyword search on pregnant inmates]

• Document delivery– Paper reproductions of older NCJRS publications and agency

final reports are available for a fee. The Sale field of the abstract will indicate "Paper Reproduction Sales.” Many recent documents published by sponsoring agencies can be ordered in hard copy from the Online Store on the NCJRS Web site.

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TOXNET

• Access (free) http://toxnet.nlm.nih.gov/– Some of the databases are available from vendors

• Coverage– Database descriptions at http://toxnet.nlm.nih.gov/cgi-

bin/sis/htmlgen?ToxNetDBDesc.htm– Search all at once or multi-database search includes

• Hazardous Substances Data Bank (HSDB), Integrated Risk Information System (IRIS), Chemical Carcinogenesis Research Information (CCRIS), and Genetic Toxicology (GENE-TOX).

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TOXNET Search Sample

• Your city has a large and thriving rat population. In the past, the city has used anticoagulant rodenticides but they don’t seem to be working as well as they had been. There has been some discussion that the rats may be resistant to warfarin or other components of the rodenticides. You want to find out whether this is prevalent and what other rodenticides might work on these resistant rats.

• Search Terms• (Rodenticides OR anticoagulants OR warfarin) AND rats

AND resistan*

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Search Results from TOXNET

• Current literature comes from PubMed with the TOXLINE [sb]

• These are older results from TOXNET Special– Warfarin-resistant rats. Greaves JH JR

Agriculture (London); 77(3): 107-10 1970 [HAPAB]

– Anticoagulant resistance in Norway rats...in U.S. cities. Bowerman AM ; Brooks J ; Jackson WB ; Kaukeinen DE. Pest Contr.; 41(4): 55, 57, 58, 60-64, 81; 1973 ; (REF:15) [HAPAB]

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Mental Health Policy Information Exchange

• Access (free) http://mimh200.mimh.edu/mimhweb/pie/

• Coverage: – Over 5,000 documents related to mental

health, substance abuse, and disability policy– Most linked to full-text reports online – No new content being added due to loss of

funding

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PIE Search Sample

• What are the characteristics of successful programs on managing adolescents with dual diagnosis (co-occurring substance abuse and mental health problems).

• Search Terms– Dual diagnosis– Adolescents

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PIE Results

• Improving Policy and Practice for Adolescent Girls with Co-occurring Disorders. Prescott,Laura. National GAINS Center for People with Co-occurring Disorders in the Justice System, 1998.

• Specialist Mental Health Services for Children and Youth - A Report of a Review of Recent and Planned Changes - New Zealand Mental Health Commission, 2001 [FT]

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AGELINE

• Access (free) http://research.aarp.org/ageline/– Also available through multiple vendors

• Coverage:– Updated regularly and includes material from

1978 on, with selected coverage of the years 1966-1977. The database covers English-language literature from many countries.

– Over 60,000 abstracts and content summaries of current literature on aging.

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AGELINE Search Sample

• You coordinate social activities for a few of the city’s 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. You’ve heard that physical activities for older adults can have a host of benefits, but there aren’t many resources with which to build a program. You must find literature supporting the effect of exercise in reducing injuries or decreasing risk of chronic disease in the elderly. Increasing client satisfaction and social engagement are secondary goals.

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AGELINE Search Terms

• Search Terms (Thesaurus of Aging Terminology)– Physical activity OR exercise– Community centers– Search specific age groups or cohorts using

subject terms (See AGELINE help)– Personal satisfaction OR Cost benefit

analysis OR economics OR falls OR program evaluation

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AGELINE Results

• Development and evaluation of "Aging Well and Healthily": a health-education and exercise program for community-living older adults. Hopman-Rock, Marijke; Westhoff, Marja H. Journal of Aging and Physical Activity Vol. 10 No. 4 (Oct 2002) 364-381

• National blueprint, increasing physical activity among

adults age 50 and older. AARP; American College of Sports Medicine; American Geriatrics Society; Centers for Disease Control and Prevention (U.S.); National Institute on Aging; Robert Wood Johnson Foundation, Princeton, NJ (Mar 2001)

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POPLINE

• Access (free) http://db.jhuccp.org/popinform/basic.html– Also available through multiple vendors

• Coverage– 300,000+ citations to scientific articles,

reports, books, and unpublished reports in population, family planning, & related issues.

– References as old as 1837, but mostly 1950 to present

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POPLINE Search Sample

• Your STD clinic is seeing more STDs in pregnant teens. The hypothesis is that since they are already pregnant, they do not feel the need to use protection. You want to find out what strategies for STD prevention in pregnant teens are effective.

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POPLINE Vocabulary and Searching

• User's Guide to POPLINE Keywords• http://db.jhuccp.org/popinform/tools/kweng.pdf• Browse or search or prepared searches [MeSH and

keywords]– Pregnancy– Adolescents– Sexually Transmitted Diseases – Pregnant Adolescents

• [use & for AND, slash for OR ; use browse feature to select multiple terms which will be combined with slashes by default – you will have to change to &]– pregnancy & stds & adolescents

• Limits (peer-reviewed journal articles)

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POPLINE Sample Results

• Crosby RA; DiClemente RJ; Wingood GM; Rose E; Lang D. Correlates of continued risky sex among pregnant African American teens. Implications for STD prevention. Sexually Transmitted Diseases. 2003 Jan;30(1):57-63.

• Oh MK; Cloud GA; Baker SL; Pass MA; Mulchahey K; Pass RF. Chlamydial infection and sexual behavior in young pregnant teenagers. SEXUALLY TRANSMITTED DISEASES. 1993 Jan-Feb;20(1):45-50.

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AGRICOLA

• Access (free) http://agricola.nal.usda.gov/ – Also available through multiple vendors

• Coverage– AGRICOLA (AGRICultural OnLine Access) is a bibliographic

database of citations to the agricultural literature created by the National Agricultural Library (NAL) and its cooperators. Database covers materials in all formats, including printed works from the 15th century. The records describe publications and resources encompassing all aspects of agriculture and allied disciplines, including food and human nutrition.

– You may search the National Agricultural Library Catalog and Journals Database at the same time.

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AGRICOLA Search Sample

• How does fear of foodborne illness play into food handling education and practice?

• Search Terms• NAL Agricultural Thesaurus

(http://agclass.nal.usda.gov/agt/agt.shtml)• Library of Congress Subject Headings

– Food safety education (or education as a broader term)

– Foodborne illness or special illnesses

• Limits: language, date, type of item

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AGRICOLA Results

• Serving up safety. Fitzgerald, P.L. School foodservice & nutrition. Sept 2002. v. 56 (8) 28-32.

• Use of the health belief model to examine older adults' food-handling behaviors. Hanson, J.A., Benedict, J.A. Journal of nutrition education and behavior. Mar/Apr 2002. v. 34 (suppl.1) S25-S30.

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Databases Questions or Comments?