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STEP 2 – SEARCHING THE EVIDENCE
Searching the Evidence: A Tool for Practitioners
(Updated March5th, 2010)
1. Determine the Question Type
Intervention (or Treatment, Prevention, Therapy)
Harm (or Causation, Etiology)
Prognosis
Diagnosis (or Assessment)
Economics (Cost-efficiency, Cost-effectiveness, and Cost-benefit studies)
Meaning (Qualitative Research)
Organizational Behaviour (Qualitative)
Theory
Not sure what these
types of questions
are? Go to page 9 in
glossary for
definitions and
examples of each
question type.
Obtaining statistics from data sources (Community Needs Assessment)
 Note: this is probably not a literature search. Consult with your
manager/supervisor to identify relevant websites and data sources
2. Develop a Searchable Question
Briefly describe the public health scenario leading to the searchable question
(Tell it as a story):
Identify terms to fit into your PICO Question
P – Population/Problem
I – Intervention or Exposure
C – Comparison/Control
O – Outcome of Interest
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Go to pages
10-14 in
glossary for
examples of
PICO
questions.
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PICO Question:
Searching the Hierarchy of Evidence
What level(s) of evidence will you search?
Note: You can choose more
than one level of evidence
for each search.
Systems (No systems
exist for public health.)
Summaries
Synopses of Syntheses
Syntheses
(Consult your Manager
if you are unable to retrieve
citations from the above
sources and to determine if a
search for single studies is
appropriate to your question.)
Synopses of Single
Studies
Single Studies
Hierarchy of Evidence
Start here with
clinical query
Systems
Summaries
Synopses of Syntheses
Go to pages 15-16 in
glossary for definitions
and examples of each
level of pre-processed
evidence.
Syntheses
Synopses of Single Studies
Single Studies
Haynes, 2007
Searching the Grey Literature
Consult with Manager/Supervisor & Librarian:

Is searching the grey literature appropriate to your research question? Will the
grey literature add value above and beyond the evidence available from the
hierarchy above?
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Sources of Grey Literature (Examples)
National and provincial policies
Ministry of Health directives and guidelines
Documents from reputable websites which outline strong research methods (e.g. World
Health Organization and the National Institute for Health and Clinical Excellence)
Guidelines from provincial advisory committees (e.g., NACI - National Advisory
Committee on Immunization)
Industry technical reports, papers and guidelines from international sources
Product Monographs
Does the grey literature conflict with the peer-reviewed research?
If yes,
proceed.
Consult with Manager/Supervisor & Librarian to determine how to
Searching Practice Reviews

Consult with Manager/Supervisor & Librarian:
Is searching practice reviews appropriate to your research question? Will practice
reviews add value above and beyond the hierarchy of evidence and/or the grey
literature?
Board of Health and Best Practice Reports
Reports from other health departments (e.g., available on website)
Reports from non-governmental, charitable or advocacy organizations (e.g., Heart and
Stroke Foundation)
Other:
Searching Information from Key Informants/Field Experts

Consult with Manager/Supervisor & Librarian:
Is searching information from key informants appropriate to your research
question? Will information from key informants/field experts add value above and
beyond the hierarchy of evidence and/or the grey literature?
Expert opinions and communication with key experts
Handouts and/or proceedings from conferences
Personal information from stakeholders in the field (e.g., phone conversation regarding a
program or strategy)
Unpublished information or documents not widely shared by a health unit or organization
Other:
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3. Document the Search Strategy
Name:
Date(s) of Search:
Database Search Strategy Worksheet
What is the PICO Question? (Copy from page 1 (step 2) of tool)
Step 1: List Your Search Terms/Identify MeSH headings
Population
Intervention Comparisons
or Exposure
Your terms
(pull key words
from pg.1 PICO
table)
Outcomes
MeSH headings
Consult the
thesaurus of each
specific database for
specific terms used
by specific
databases (e.g., in
MEDLINE these
terms are MeSH
headings, other
databases use other
terms)
Source: Health-evidence.ca. (2009, November 25). Developing an Efficient Search Strategy. Retrieved
02/20/10 http://www.healthevidence.ca/public/tools/16/Developing_an_Efficient_Search_Strategy.doc.
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Go to pages
18 -19 in
glossary for
example and
guidance on
search terms
(e.g., Boolean
Logic and
search
symbols).
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Step 2: List the Inclusion and Exclusion Criteria for the Search
 Identifying the inclusion and exclusion criteria for your search will help to refine
your search and retrieve the most relevant articles; the limits you are able to place
on your search will differ depending on the database used. (The list below is not
exhaustive.)
Inclusion Criteria
Language:
Country/Location:
Publication Date:
from:
to:
Age group:
Cultural group:
Publication type:
Study type:
Review articles:
Other:
Exclusion Criteria
Language:
Country/Location:
Publication Date:
from:
to:
Age group:
Cultural group:
Publication type:
Study type:
Review articles
Other:
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Go to pages
20-22 in
glossary for
descriptions
of sample
databases.
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Step 3: Follow the Hierarchy of Evidence & Identify the Appropriate Databases
for your Search
Evidence Hierarchy
i) Summaries
Identify Sources/Databases Searched
Are summaries available?
Yes
No
Source(s):
ii) Synopses of
Syntheses
Are synopses of syntheses available?
Yes
No
Source(s):
Healthevidence.ca
Other: (e.g., TRIP Database):
iii) Syntheses
Are syntheses available?
Yes
No
Source(s):
MEDLINE/PubMed
The Cochrane Library (Cochrane Database of Systematic
Reviews)
Other:
Note: The preferred Medline interface is Ovid. Medline (Ovid)
and The Cochrane Library should be your two primary
databases for searching systematic reviews. If relevant
systematic reviews are not retrieved through these two
databases initially, you may consider searching in:
i)
Other bibliographic databases (e.g, CINAHL and
PyscINFO)
ii)
Discipline Specific Websites (e.g., TOXNET &
National Collaborating Centre for Environmental
Health)
 Consult with Library: if searching for literature
in a sector or discipline specific website that you are
unfamiliar with
Note: As you move from bibliographic databases to
discipline specific websites, the time spent searching
increases, and the likelihood of finding quality studies
decreases.
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Consult with your Manager/Supervisor & Librarian if unable to retrieve citations from the
above sources to determine if a search for single studies is appropriate to your question.
iv) Synopses of Single
Studies
Are synopses of single studies available?
Yes
No
Source(s):
v) Single Studies
Are single studies available?
Yes
No
Source(s):
vi) Other:
Grey Literature,
Practice Reviews &
Information from Key
Informants/Field
Experts
Is relevant and value-added evidence available from these
sources?
Yes
No
Source(s):
Step 4: Citations Retrieved – Assessing the Pool of Potential Evidence
How many citations were retrieved?
Consider the number of articles retrieved in your search. A large number retrieved
may require you to refine the search strategy further (e.g., place further limits on the
search). A small number of articles retrieved may require expanding your search
strategy.
Depending on your topic, the number of studies required to answer your PICO will
differ, and will also depend on the types of studies retrieved. For example, a search
that retrieves three relevant systematic reviews of strong methodology may be
adequate for your topic at hand.
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Can you proceed to the critical appraisal stage with the pool of citations the search
strategy has generated?
Yes – Complete the “Overview of Search Process” [insert link here] (pg. 24 of
glossary)
No - too many citations
 Action: (a) reduce keywords, (b) put more limits on the inclusion/exclusion
criteria and/or (c) limit to particular databases
No - too few citations
 Action: (a) expand keywords, (b) remove some of the limits on
inclusion/exclusion criteria, (c) search additional databases
Step 5: Saving your Search
Have you imported your references into Refworks?
Yes
No
Have you saved your search?
Yes - Where is it saved? (location/filename)?
No
Go to pages
22-23 in
glossary for
information on
how to save
your search
Note: You can alternatively cut and paste the search details in the textbox below (see
details on saving your search on pages 22-23 in glossary):
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Searching the Evidence Tool
Glossary
Determining Question Type
Question Type
Intervention,
Prevention,
Therapy
Definition
Determining the effect of
different interventions on
improving patient function or
avoiding adverse events.
Ascertaining the effects of
potentially harmful agents on
patient function, morbidity,
and mortality
Example
Can a multi-component obesity
prevention program in a secondary
school increase adolescent physical
activity?
Are there any long-term adverse
reactions associated with immunizations
for meningococcal disease in young
adults?
Prognosis
Estimating the future course of
patient’s disease or condition
Diagnosis (or
Assessment)
Establishing the power of a
diagnostic tool to differentiate
between persons with and
persons without a target
condition or disease
Studying the economic
efficiency of health care
programs or interventions
What are the health effects in young
children due to chronic consumption of
private well water containing excessive
lead concentrations?
Are there demographic and psychosocial
risk factors that can be used to develop a
predictive index for HPV infection in
females under 20 years of age?
Harm (or
Causation,
Etiology)
Economic
Evaluation
Meaning
Describing, exploring, and
explaining phenomena being
studied (focus on process
rather than outcome)
Is social marketing for community
prevention strategies for West Nile
Virus cost effective in rural
communities?
What are adolescent experiences of
seeking peer-counselling for sexual
health matters in secondary schools?
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Organizational
Behaviour
Exploring and explaining the
factors and outcomes of an
organizational change,
initiative or process. For
example, questions regarding
knowledge exchange within an
organization, staff professional
development, etc.
Does building sustained relationships
with academic partners increase
research utilization by a health services
organization?
Theory
Describing and exploring the
theories for a particular topic
area in order to guide decision
making.
What are the theoretical underpinnings
for ideal growth and development from
0-12 months?
(Source: DiCenso, A.., Guyatt, R., Ciliska, D. Evidence-Based Nursing: A Guide to Clinical Practice; Ciliska, D,
Thomas, H., Buffett, C., A Compendium of Critical Appraisal Tools for Public Health Practice. National
Collaborating Centre for Research Methods and Tools, Feb 2008)
Developing a Searchable Question
PICO = an acronym used to develop a searchable research question
P – Population/Problem
I – Intervention or Exposure
Describe the group that is relevant to your research
question.
Examples: Adolescents, Youth, Children, Adults
Identify the intervention or exposure.
Public health interventions can include such activities
as educational programs, policy, media campaigns,
counselling. The exposed group is often used to
connote members who have been exposed to a
supposed cause of a disease or health state of interest
or possess a characteristic that is a determinant of the
health outcome of interest.
Example: high exposure to environmental tobacco
smoke is known to cause cancer.
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C – Comparison/Control
O – Outcome of Interest
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Identify the comparison/control intervention or
group.
This can be a standard therapy, though it may also be
no intervention, a placebo or an alternative treatment,
exposure or diagnostic test
Identify the outcome that is relevant to your
population or problem.
The outcome is the thing that is being measured, and
it is not phrased using directional language.
Examples: “months of breastfeeding” or “rates of
immunization” (not “more/less months of
breastfeeding” or “higher/lower rates of
immunization”)
Example: (Chronic Disease and Injury Prevention)
You are interested in identifying school-based interventions which improve eating
behaviours and decrease body-mass index (BMI) among secondary school students.
You decide to focus on increased fruit and vegetable consumption as the key indicator
for improved eating behaviours.
The following PICO question can be developed for the above scenario:
Secondary school students
P – Population/Problem
I – Intervention or Exposure
School-based healthy eating programs
C – Comparison/Control
Schools that only have standard health education
programs
Fruit and vegetable consumption and body-massO – Outcome of Interest
index (BMI) of students
PICO Question: Do secondary school students who are exposed to school-based
healthy eating programs have higher fruit and vegetable consumption and lower
BMIs as compared to students in schools that only have standard health education
programs?
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Example: (Communicable Disease Division)
You are interested in knowing if newer electronic technologies (e.g., internet,
facebook, cell phones, texting, and email) offer any advantages over traditional
methods to complete contact notification for case management of STIs.
The following PICO question can be developed for the above scenario:
Contacts of clients diagnosed with reportable
P – Population/Problem
sexually transmitted infections
Using technological techniques of informing contacts
I – Intervention or Exposure
(internet, facebook, cell phones, texting, email, etc)
Traditional methods of letters and/or phone calls.
C – Comparison/Control
O – Outcome of Interest
Efficiency and effectiveness of technological
strategies to inform contacts.
PICO Question: Are contacts of clients diagnosed with an STI informed more
efficiently and effectively using internet/facebook/email/etc as compared to contacts
of clients who are informed via traditional methods (i.e., letters and phone calls)?
Example: (Environmental)
A parent is concerned about the potential health impacts of children exposed to
chemicals that are present in crumb rubber used in indoor artificial turf. Parents
smell a chemical whenever the children are using the facility for soccer, primarily
during late fall and winter months.
The following PICO question can be developed for the above scenario:
Children
P – Population/Problem
I – Intervention or Exposure
Exposure to chemical in crumb rubber from indoor
turfs used once a week for approximately 2 hours
each time (oral, dermal and inhalation)
C – Comparison/Control
O – Outcome of Interest
Health risks associated with exposure to these
chemicals
PICO Question: What are the health risks to children associated with oral, dermal
and inhalation exposure to chemicals present in crumb rubber used in indoor
turfs/fields?
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Example: (Epidemiology)
You are interested in identifying pre-natal risk factors associated with low birth
weight babies and still births.
The following PICO question can be developed for the above scenario:
Pregnant women
P – Population/Problem
I – Intervention or Exposure
Prenatal exposure to risk factors
C – Comparison/Control
No prenatal exposure to risk factors
O – Outcome of Interest
Number, incidence, prevalence of low birth weight
babies and/or still births
PICO Question: What prenatal exposures are associated with low birth weight
babies and/or stillbirths among pregnant women?
Example: (Family Health)
You are interested in developing a campaign to increase awareness among the Peel
population regarding the benefits of breastfeeding. You would like to search the
literature to identify the associations between exclusive breastfeeding prior to six
months of age, and cognitive development.
The following PICO question can be developed for the above scenario:
Healthy full term infants less than 6 months of age,
P – Population/Problem
living in developed countries
Exclusive breastfeeding or provision of breast milk
I – Intervention or Exposure
only (no other artificial milk substitutes)
Healthy full term infants less than 6 months of age,
C – Comparison/Control
living in developed countries, who are given both
breast milk and formula
Cognitive development, social intelligence, learning
O – Outcome of Interest
potential, short term intelligence (childhood) and
long term intelligence (adult)
PICO Question: Is exclusive breastfeeding until 6 months of age among healthy full
term infants in developed countries associated with improved cognitive development,
social intelligence, learning potential and short and long term intelligence as
compared to the provision of both breast milk and formula among infants of the same
description?
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Example: (Office of the MOH)
In an attempt to define the concept of culturally competent public health services, we
are interested in identifying the effectiveness of providing public health programs
ensuring culturally appropriate language services for multicultural communities vs.
public health programs delivered in the mainstream language only (i.e. English).
The following PICO question can be developed for the above scenario:
Ethno-culturally diverse populations (eg. Recent and
P – Population/Problem
established immigrants, visible minority and less
visible minority groups, language and religious
groups etc.)
Providing culturally appropriate language services for
I – Intervention or Exposure
all public health programs or community health
interventions: translation/interpreter services;
multilingual services; culturally tailored health
promotion or patient education interventions;
Mainstream population being offered public health
C – Comparison/Control
programs in the official language (i.e. English)
Health outcomes; Self-related health status; Client
O – Outcome of Interest
satisfaction/access/participation;
PICO Question: Does providing public health programs ensuring culturally
appropriate language services improve: access to and use of public health services
offered in ethno-culturally diverse communities, increase client satisfaction and/or
result in improved perceived health or health status indicators when compared with
the delivery of the same programs using only the mainstream official language(s)?
Forms of Evidence
Peer-reviewed research: is scholarly work, research or ideas that have been
subjected to the scrutiny of other who are experts in the same field; evidence that is
retrieved through standard searchable databases.
Grey literature: refers to material that is not formally published, such as institutional
or technical reports, working papers, or other documents not normally subject to
editorial control or peer-review. It may be widely available yet difficult to trace
through conventional channels such as through publications or bibliographic
databases. In the context of this tool, grey literature refers to material that is still of
very strong methodology and high quality, such as reports prepared by WHO or
NICE.
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Practice Reviews: refers to relevant documents collected from other organizations in
the field, such as reports from other health departments. Practice reviews are not
published material, are typically found through an internet search, and include
documents or reports available on an organization’s website.
Information from Key Informants/Field Experts: refers to sources of unpublished
information that we retrieve through informal channels. For example, information we
retrieve through a professional listserv or through contact (e.g., email or telephone)
with an expert or colleague in the field.
Realist Reviews: can be considered an ‘up and coming’ form of evidence. A realist
review is an evolving design whereby it may take the form of a peer-reviewed paper
which applies a realist synthesis in a systematic and rigorous way; or whereby it is an
approach taken by a field expert or organization to examine a particular topic. A
realist review takes an explanatory versus a judgemental focus and aims to examine
all the factors which should be considered in the decision-making process; that is, the
qualitative and quantitative evidence, as well as situational and contextual factors
(e.g., political climate and why a program may or may not be effective in a particular
setting). For example, a realist approach would examine not only whether or not a
program was effective, but under what conditions and for which target groups it was
effective. Realist reviews may fit into a variety of levels of evidence (e.g., synthesis
or grey literature) depending on the approach taken and from where they are
retrieved.
Note: As you move down the hierarchy of evidence and through the various forms of
evidence, you are also moving through a spectrum of quality, with the highest quality
being the peer-reviewed literature. Accordingly, each level of evidence would be
weighted differently based on this hierarchy.
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Levels of Evidence
Source: Robeson, P. Evidence-Informed public health: Searching for Public Health Evidence- the 6 Ss of searching.
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Levels of
Evidence
Systems
Summaries
Synopses of
Syntheses
Syntheses
- 17 -17
Hierarchy of Evidence: Definitions and Examples
Definition
Examples:
Decision support services that
match information from
individual patients with the best
evidence from research that
applies (Haynes, 2007).
Note: No such system currently
exists in the public health
setting.
Integrates the best available
evidence from lower layers to
provide a full range of evidence
concerning management options
for a given health problem
(Haynes, 2007).
Synopses of systematic reviews
that encapsulate the key
methodological details and
results required to apply the
evidence (Haynes, 2001)
Systematic consolidation of the
literature on a specific topic.
Computerized decision
support systems (CDSS)
Clinical Practice Guidelines
Evidence-Based Textbooks
Healthevidence.ca
Evidence-based abstract
journals
CDC ranked sites
Cochrane Library Reviews
Campbell Collaboration
Reviews
Consult your Manager if unable to retrieve citations from the above sources to
determine if search for single studies is appropriate.)
Synopses of
Single Studies
Studies
Synopses of individual studies
that encapsulate the key
methodological details and
results required to apply the
evidence (Haynes, 2001).
Contributes to clinical decisions
if no higher level of
preprocessed evidence is
available.
Evidence-based abstract
journals
PubMed clinical queries
CINAHL clinical queries
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Converting the PICO Question into a Search Strategy
To convert your PICO questions into a search strategy, always consult the MeSH
to identify appropriate key terms to conduct search:
1) “Your Terms” – brainstorm relevant terms for each section of the PICO
question
2) MeSH headings – identify the appropriate MeSH terms in MEDLINE that
match “your terms”
Note:
 Think of alternate spellings, synonyms and truncations (*)
(Note: Consult the thesaurus of each specific database for specific terms used
by the database. Eg: If using MEDLINE for your search, use “MeSH”
(Medical Subject Heading) terms in your search.
 Use Boolean operators (AND, OR, NOT) to narrow or expand search strategy
(see below for definitions)
Example: You are interested finding out if quit and win contests are effective in
producing short-term and/or long-term quit rates among adults.
Population
Your terms
(pull key words
from pg.1 PICO
table)
Adults
MeSH headings
Adults
Consult the
thesaurus of each
specific database for
specific terms used
by specific
databases (e.g., in
MEDLINE these
terms are MeSH
headings, other
databases use other
terms)
Intervention
or Exposure
Quit and Win
Contest
Smoking
cessation
Competition
Comparisons
Outcomes
No intervention
Short-term
quit rates
-----
Long-term
quit rates
Smoking
cessation;
Tobacco use
cessation
Contest
Prize
In the example above, the terms “quit and win contest” and “quit rates” are not terms
indexed under MeSH. Alternative terms that are indexed in MeSH are provided above
and should be used when developing your search strategy.
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Understanding Boolean Logic
Boolean logic consists of three logical operators: OR, AND & NOT
Boolean Operators:
 OR logic finds studies containing either of the specified words/phrases, and
broadens your search
 AND logic finds studies containing both specified words/phrases, and narrows
your search
 NOT logic excludes records from your search results
Note: “*” is a truncation symbol that means further letters can be added to the word
Each operator can be visually described by using Venn diagrams, as shown
below:
Boolean Operator : OR
college OR university
OR logic is most commonly used to search for
synonymousterms or concepts.
The more terms or concepts we combine in a search
with OR logic, the more records we will retrieve.
Boolean Operator: AND
poverty AND crime
The more terms or concepts we combine in a search
with AND logic, the fewer records we will retrieve.
A few Internet search engines make use of the
proximity operator NEAR. A proximity operator determines the closeness of terms
within the text of a source document. NEAR is a restrictive AND. The closeness of
the search terms is determined by the particular search engine. Google defaults to
proximity searching by default.
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Boolean Operator: NOT
cats NOT dogs
NOT logic excludes records from your search results.
Be careful when you use NOT: the term you do want
may be present in an important way in documents that
also contain the word you wish to avoid.
Search symbols
/
after an index term indicates that all subheadings were selected.
*
before an index term indicates that that term was focused - i.e. limited to
records where the term was a major MeSH term.
"exp" before an index term indicates that the term was exploded.
.tw.
indicates a search for a term in title/abstract
.mp.
indicates a free text search for a term
.pt.
indicates a search for a publication type
$
at the end of a term indicates that this term has been truncated.
?
in the middle of a term indicates the use of a wildcard.
adj
indicates a search for two terms where they appear adjacent to one another
Search Terms
Text Words for Searching in MEDLINE, CINAHL, and PsycINFO
Clinical Query
Text Words
Therapy/Intervention
Clinical trial*, controlled trial*, double-blind, placebo*
Diagnosis
Diagnosis, diagnostic use, predictive value, sensitivity,
specificity
Etiology
Case control, cohort, etiolog*, odds ratio*, relative
risk*
Prognosis
Follow-up, followup, morbidity, mortality, outcome*,
predict*, prognos*
Systematic Review
CINAHL, MEDLINE, PsycINFO, PsycLit, critical
analys*, integrative review*, meta-anal*, systematic
review*
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Clinical Practice Guideline
Qualitative Studies
Guideline*, standards
Interview*, listen*, observ*, phenomenology*,
qualitative*, quality of life,questionnaire*, survey*,
triangulat*
*Asterisk indicates the term is to be truncated
Description of Search Engines
Search Engine
Definition
Produced
by:
OVID
OVID is a search engine that allows you to
search multiple databases (e.g., PubMed,
CINAHL, Global Health) simultaneously.
Wolters
Kluwer Health
Search Tips
Uses Boolean Operators
Uses MeSH (Medical
Subject Headings)
Description of Sample Databases
Sample
Database
Definition
Produced
by:
Academic Search
Premier
The world’s largest multi-disciplinary
database containing full text for nearly 4,500
journals, including more than 3,600 peerreviewed titles. Areas of study include: social
sciences, humanities, education, computer
sciences, engineering, language and
linguistics, arts and literature, medical
sciences and ethnic studies.
The Cumulative Index to Nursing & Allied
Health Literature database provides
authoritative coverage of the literature related
to nursing and allied health literature. The
database provides full text for more than 600
journals.
EBSCO
Publishing
Uses Boolean Operators
Cinahl
Information
Systems
Uses Boolean Operators
CINAHL with Full
Text
Search Tips
Uses CINAHL thesaurus
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Cochrane Central
Register of
Controlled Trials
(CCRCT)
- 22 -22
Contains more than 300,000 bibliographic
references to controlled trials in health care
that are registered as relevant for inclusion in
Cochrane Reviews.
The Cochrane
Collaboration
Uses Boolean Operators
Note: The
Cochrane
Library
includes 7
databases in
total.
Uses MeSH (Medical
Subject Headings)
Search can be limited to:
 A specific title
 Particular date range
Note: When searching the Cochrane
Library, you automatically search all
7 databases at once. (You can select
to search one database by using the
Advanced Search Feature).
Cochrane Database
of Systematic
Reviews (CDSR)
This database in the Cochrane Library brings
together all the currently available Cochrane
Reviews and Protocols for Cochrane Reviews.
The Cochrane
Collaboration
Note: The
Cochrane
Library
includes 7
databases in
total.
Uses Boolean Operators
Uses MeSH (Medical
Subject Headings)
Search can be limited to:
 A specific title
 Particular date range
Note: When searching the Cochrane
Library, you automatically search all
7 databases at once. (You can select
to search one database by using the
Advanced Search Feature)
Database of
Abstracts of
Reviews of
Effectiveness
(DARE)
This full-text database contains critical
assessments and structured abstracts of
systematic reviews from health care journals
from around the world. It covers topics such
as diagnosis, prevention, rehabilitation,
screening, and treatment.
National
Health
Services
Center for
Reviews and
Dissemination
(NHS CRD) at
University of
York, England
Uses Boolean Operators
Uses MeSH (Medical
Subject Headings)
Search can be limited to:
 A specific title
 Particular date range
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EMBASE
(Excerpta Medica
Database)
Database covering the worldwide literature
on biomedical and pharmaceutical fields.
Indexes a large proportion of the European
biomedical and science literature.
Elsevier
Science
ERIC (the
Educational
Resource
Information
Centre)
Provides access to education literature and
resources. ERIC provides full text of more
than 2,200 digests along with references for
additional information and citations and
abstracts from over 1,000 educational and
education-related journals.
ERIC
Clearinghouse
system
EMBASE uses EMTREE, a
hierachically ordered controlled
vocabulary. (Note: EMTREE terms
are different from MeSH terms and
should not be confused when
performing searches.)
Use the Thesaurus of ERIC
Descriptors – the Thesaurus uses a
controlled vocabulary.
Uses Boolean Operators
Search can be limited to:
 A specific title
 Particular date range
MEDLINE
Nursing & Allied
Health Collection:
Comprehensive
Edition
Provides authoritative medical information on
medicine, nursing, dentistry, veterinary
medicine, the health care system, pre-clinical
sciences, biological and physical sciences,
humanities as well as many more. Contains
citations from over 4,800 current biomedical
journals.
U.S. National
Library of
Medicine
Database contains nearly 400 full text
journals, including nearly 300 peer-reviewed
titles covering the areas of nursing,
biomedicine, health sciences, consumer health
and allied health disciplines. Nursing, and
many more.
EBSCO
Publishing
Uses Boolean Operators
Uses MeSH (Medical
Subject Headings)
Search can be limited to:
 A specific title
 Particular date range
Uses Boolean Operators
Search can be limited to:
 A specific title
 Particular date range
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PsycINFO
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Professional and academic literature in
psychology and related disciplines including
medicine, psychiatry, nursing, sociology,
education, pharmacology, physiology,
linguistics, and other areas.
The American
Psychological
Association
Use the Thesaurus of Psychological
Index Terms to choose descriptors or
subject headings that describe your
concepts. The Thesaurus provides
the official terminology or
authoritative list of subjects used in
the database.
Uses Boolean Operators
Search can be limited to:
 A specific title
 Particular date range
The Psychology &
Behavioral
Sciences Collection
TRIP Database
Database providing nearly 600 full text
publications, including nearly 550 peerreviewed journals. The database covers topics
such as emotional and behavioral
characteristics, psychiatry & psychology,
mental processes, anthropology, and
observational and experimental methods.
UK clinical search engine. The primary goal
of the TRIP database is to provide clinicians
and other health professionals with timely,
evidence-based answers to clinical questions.
The TRIP database searches multiple sites and
filters results into various categories (based on
an evidence-based medicine hierarchy),
including: evidence-based synopses,
systematic reviews, primary research, online
textbooks and resources, clinical questions
and answers, and guidelines from various
countries.
EBSCO
Publishing
Uses Boolean Operators
Search can be limited to:
 A specific title
 Particular date range
TRIP Database
Ltd.
Uses Boolean Operators
Search can be limited to:
 A specific title
Adapted from: The George Washington University Medical Centre; The Cochrane Collaboration 2005. Virtual Library – EBSCO Host.
Limiting your Search
What limits did you place on your search?
If the number of hits that you retrieve from your search is too large, you may need to further
refine your search by placing limits. A search that retrieves 3-5 high quality systematic
reviews, for example, may be ideal for your topic.
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You can place limits on many items, including: publication years, publication types (e.g.,
systematic reviews and RCTs), and language. The limits you can place on your search will
vary by database.
Saving your Search
Saving your search is important since it will allow for your search to be replicated or updated
in the future, and ensures transparency in your methodology.
The methods for saving your search will differ based on the databases you are using. Look
for save functions in the databases you are using that will allow you to edit your searches at a
later time. In Medline (Ovid) you can save your search by going to the results manager, and
clicking on the ‘search strategy’ box, and then clicking on ‘display’. You can also save your
search history, email it to yourself and copy and paste into your worksheet.
You can copy and paste your search details directly into your ‘Database Search Strategy
Worksheet’, including:
 Key terms used in the search
 Boolean operators used to expand or refine searches
 Limits placed on the date of publication (e.g., articles published from 2000-2009)
Here is an example of the search details provided by Medline (Ovid) for a search on Quit and
Win Contests for Smoking Cessation. Cutting and pasting the search details into the textbox
provided in the “Database Search Strategy Worksheet” is found below. Documenting the
search details will allow you to repeat your search at a later time if needed.
Database: Ovid MEDLINE(R) <1950 to February Week 4 2010> Search Strategy:
-------------------------------------------------------------------------------1 Smoking Cessation/ (14007)
2 smok$ cessat*.tw. (10251)
3 1 or 2 (17522)
4 ((quit adj win*) or (competition* or contest* or prize*)).tw. (51350)
5 3 and 4 (120)
6 limit 5 to yr=2008-2010 (21)
7 from 6 keep 1-21 (21)
8 from 7 keep 1-21 (21)
Database: Ovid MEDLINE(R) <1950 to February Week 4 2010> Search Strategy:
-------------------------------------------------------------------------------1 Smoking Cessation/ (14007)
2 smok$ cessat*.tw. (10251)
3 1 or 2 (17522)
4 ((quit adj win*) or (competition* or contest* or prize*)).tw. (51350)
5 3 and 4 (120)
6 limit 5 to yr=2008-2010 (21)
7 from 6 keep 1-21 (21)
8 from 7 keep 1-21 (21)
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Using the Overview of Search Process for the Final Report
The Overview of Search Process (pg. 24) should be included in the appendix of your final
report. This template allows the reader to review the databases searched, the number of
citations retrieved for each database, and the number of citations deemed relevant to your
research question. This template can be accessed at [insert link here]
Revising your Search
If you have not found the information you are looking for to answer your research question,
you may consider repeating your search again, using:
a) different databases
b) different search terms
c) reference lists available from retrieved articles
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Overview of Search Process
(date)
Systems (#)
Summaries (#)
Syntheses (#)
Synopses of
Syntheses (#)
Synopses of
Single studies (#)
Single
Studies
(#)
(#)
Total identified articles (#)
Removal of duplicates
Duplicates (#)
Primary relevance assessment
Non-relevant (based on title
and abstract screening) (#)
Potentially relevant articles (#)
Relevance assessment of full document versions (#)
Non-relevant articles (#)
Relevance
Relevance
criteria #1
criteria #3
(#) Relevance
(#)
criteria #2 Total relevant articles (#)
(#)
Quality assessment of relevant articles (#)
Weak articles
(#)
Strong articles (#)
Moderate articles (#)
Source: Health-evidence.ca. (2009, November 25). Keeping Track of Search Results: A Flowchart. Retrieved [insert date you downloaded
this document e.g., January 13, 2010],
Link to tool: http://www.health-evidence.ca/public/tools/10/Keeping_Track_of_Search_Results_-_A_Flowchart.ppt.
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The Library will manage distribution of journal articles for review/critical appraisal
by the Rapid Review Teams. Below are some guiding Copyright Principles for
acquisition of articles for critical appraisal. The lead on each Rapid Review Team
will inform the library as to the names of individuals requiring articles.
Copyright Principles guiding Journal articles for Critical Appraisal
1. The Library is allowed to send a paper copy for personal study.
2. The Library is not allowed to send PDF’s (electronic copies) of
articles.
3. Both Peel Public Health employees and people working with Peel
Public Health may receive one paper copy (per person) for personal
study.
4. If the Library subscribes to an electronic journal, Peel Public Health
employees can click on the link to the article, and read on screen or
print.
5. Electronic copies of articles may not be stored in central locations,
such as EIM.
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References
DiCenso A, Guyatt R, Ciliska D. Evidence-Based Nursing: A Guide to Clinical Practice.
St. Louis: Mosby; 2005.
Ciliska D, Thomas H, Buffett C. A Compendium of Critical Appraisal Tools for Public
Health Practice [Internt]. National Collaborating Centre for Research Methods and Tools;
February 2008. [cited 2010 Dec 6]. Available from:
http://www.nccmt.ca/pubs/2008_07_Compendiumtooleng.pdf
Haynes RB. Of studies, summaries, synopses, and systems: the “4S” evolution of services
for finding current best evidence. Evid Based Mental Health. 2001;4:37-9.
Haynes RB. Of studies, summaries, synopses and systems: the “5S” evolution of
information services for evidence-based healthcare decisions. Evid Based Nurs. 2007;
10:6-7.
Robeson P, Dobbins M, DeCorby K, Tirilis D. Facilitating Access to Pre-Processed
Research Evidence in Public Health. BMC Public Health. 2010;10:95.
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