Find health information strategically
|Step 1: Define your research question
Use the PICO mnemonic to frame a well-formed clinical question.
The research question lays the foundation for the literature search.
|► Determine the PICO components of your question
|Problem, Patient, and/or Population
|– Who is the patient or population?
– What is the problem, condition, or issue?
|Intervention or Exposure
|– What is the proposed treatment?
– What is the proposed test or procedure?
– What is the factor of interest?
|– Am I comparing with another intervention or exposure?
|– What do I hope to improve, measure, or accomplish?
|► Frame the PICO question
|Example PICO question
For patients with a history of heart attacks (P), is aspirin (I) more effective than other antiplatelet aggregators (C) in preventing further heart attacks (O)?
|Step 2: Concentrate on the key concepts
Less is more.
Impose fewer restrictions to get more search results.
|► Focus on 2 or 3 ideas from your question
Start your search with these concepts:
In general, the problem and intervention concepts are more clearly defined in the titles and abstracts of publications.
|Step 3: Gather search terms
We can express the same idea using different words and phrases.
If you include different terms with similar or related meanings in your search, you may find a broader range of results.
|► Collect terminology for each concept
Consider the following types of terms:
|Types of terms
|hypertension, high blood pressure
|AIDS, ALS, MRI, SIDS
|CO2, bp, ddx
|viscus – viscera, femur – femora
|Professional or research terms
|cerebrovascular accident for stroke
|Slang or vernacular terms
|bounceback for readmission
|pediatrics – paediatrics (US & UK)
|cancer, malignancy, tumor
Try these additional ways for identifying search terms:
► Consider other types of similar terms →
► Run a preliminary database search and examine the results for helpful language.
|Example search terms
|Step 4: Write the search statement
The search statement is the text entered into the search box.
|► Arrange your search terms in this pattern
|Search statement template
Fill in the blanks with
Concept #1 terms
Fill in the blanks with
Concept #2 terms
Add more search terms or concepts using the proper operator: OR, AND, or ( ).
|Example search statement
(heart attack OR myocardial infarction OR heart infarction OR AMI OR MI) AND (aspirin OR acetylsalicylic acid OR ASA)
The search operators define the logical relationships between search terms. Here are the ways:
► OR joins similar terms – such as synonyms and related concepts.
► AND combines different concepts.
► Parentheses ( ) group together similar terms into a conceptual unit.
|Step 5: Search a database
Databases are searchable collections of information.
You have several database options for health literature searching.
|► Choose a database specializing in your topic
We recommend the following databases as starting points for your research.
|► Databases for extensive searching
Use the following databases for a comprehensive literature search.
They are suitable for research projects.
|All health specialties
|All health topics. A popular database.
|All health topics. Specialized in pharmacology.
|Psychiatry and psychology
|Behavioral and social sciences focus
|Nursing and allied health
|Nursing and allied health (OT, PT, RD, SLP) literature
|Biology, genetics, and basic health sciences focus
|Web of Science
|Diverse research fields. Beneficial for multidisciplinary topics.
|► Databases for summaries of research
Use the following databases to find reviews of research literature.
Reviews are helpful when you're short on time.
|Types of Reviews
|Literature reviews and
|Filter your search results for reviews or systematic reviews
|Find clinical recommendations and research summaries
|► Databases for clinical support
Use the following databases to find research on clinical practice and care.
Caution: Search results in these databases may exclude non-clinical literature.
|Clinical search engines
|PubMed Clinical Queries
|Filter results for therapy, diagnosis, etiology, prognosis, and clinical prediction guides
|Search evidence-based information for clinical practice and care
|► Run the search
Enter your search statement into the database search box.
|(heart attack OR myocardial infarction OR heart infarction OR AMI OR MI) AND (aspirin OR acetylsalicylic acid OR ASA)
View this search in a database:PubMed
To get a comprehensive search, use multiple databases.
|Step 6: Make search refinements
|► Evaluate the search results for gaps
|Do the publications address your research question?
|Do the results cover your research topics? Are there topics missing?
|Are the publications too specialized? or too general?
|Is the quantity of results lower than expected? or higher?
|Are there notifications of database errors?
|► Change the scope of the search
|When this happens:
|I have many results that do not relate to my topic
|Focus the search
|I have few results
|Expand the search
|► Ways to focus the search
|Use a more specific topic
|Instead of: mental illness
Search for: depression
Instead of: back pain
Search for: low back pain
|Place “double quotes” around phrases
|Instead of: quality of life
Search for: “quality of life”
Double quotes let you define precisely how the words will appear.
Without them, results may have the terms in a different order.
|Use the sidebar filters to sift through results by features, including publication date, article type, study design, and more.
PubMed filters in the sidebar
|Use controlled vocabulary to enhance the search
Controlled vocabulary is the standardized terms that describe and organize medical topics in a database.
Databases mark publications with controlled vocabulary to summarize the subject matter.
How to use controlled vocabulary in a PubMed search:
– Make a note of the MeSH terms of interest and add them to your search statement.
|Add an extra topic
|Instead of: mental health AND exercise
Search for: mental health AND exercise AND mood
Try more ways to focus the search →
|► Ways to expand the search
|Add similar terms
|Instead of: hypertension
Search for: hypertension OR high blood pressure
Instead of: quality of life
Search for: quality of life OR patient satisfaction OR resilience
|Use a broader topic
|Instead of: aortopulmonary septal defect
Search for: congenital heart defects
|Examine similar articles
|Databases often suggest comparable publications for an article.
In PubMed, look to the "Similar articles" section beneath the item's abstract.
|Eliminate a topic
|Instead of: heart attack AND aspirin AND high blood pressure
Search for: heart attack AND aspirin
Try more ways to expand the search →
A literature search is an iterative process. You will:
– Run a preliminary search
– Evaluate the search results
– Revise the search strategy to address any gaps
– And repeat the process