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Topics
• Clinical queries and other tools• Search construction: controlled vocabulary and Boolean
searching• Advanced search and limits• Managing results: export citations, save searches and
collections, customize retrieval
Tour
Clinical queries
Special queries and subjects
Single citation matcher
Search construction• Identify relevant concepts, including controlled vocabulary• Combine concepts w/ appropriate Boolean logic• Use special features or limits to refine results
IDENTIFYING CONCEPTSMedical Subject Headings (MeSH)
Search construction: Concept building
• Identify major concepts• Identify preferred terms for concepts (including
subheadings if relevant)• Identify synonyms for major concepts
Review: Keywords vs. controlled vocabulary
Keywords
Controlled
vocabularies
Search construction: Vocabulary
Keywords
Controlled
vocabularies
What are they? Literal search Looks for occurrences of words
When to use? Current topics Difficult-to-describe concepts No vocabulary exists in database
Examples Drug names (Lipitor, Prozac) Slang Concepts (Swine flu, oil spill)
Search construction: Vocabulary
Keywords
Controlled
vocabularies
What are they? Set of words or phrases used to
describe concepts Dictionary of accepted terms for a
database
When to use? Searching a database that uses one
Examples MeSH (Medical Subject Headings) EMTREE (Embase)
MeSH entry - pathology
Subheading: pathology
Shortcuts to MeSH• ‘Search details’ from results screen• View MeSH indexing from relevant citations• Use Advanced search > ‘Search builder’ feature with MeSH
dropdown selected
Identify MeSH terms: Use ‘Search details’
Details
ID MeSH: Citation indexing
Identify MeSH: Search builder
Searching MeSH from PubMed
MeSH database• Identify MeSH headings • Entry terms can suggest keywords for comprehensive
searches• Hierarchy view can help identify more relevant
(broader/more focused) terms• Subheadings can help refine search
• Focus on specific application of MeSH: eg bronchiolitis/drug therapy
• Search builder exports MeSH term to PubMed
Question 1:• Does Epstein Barr virus cause a chronic hepatitis, in
particular one that resembles autoimmune hepatitis?
• Try: keyword search
• Try: Clinical queries, using etiology as a filter
• Try: MeSH (+/- keywords)• Epstein-Barr virus infections [mh] AND hepatitis, autoimmune [mh]
Results 1
COMBINING CONCEPTS
Review: Boolean Logic
Concept 1
Child
Children
Adolescent
Teenager
Concept 2
Obesity
Obese
Overweight
BMI
Concept 3
Mortality
Premature deathAND ANDOR
OR
OR
OR
OR
OR
OR
Combining concepts - searchline• Use parentheses to group related concepts• Capitalize Boolean operators
Combining concepts – search builder
Combining concepts – search history
Question 2• What are the cytologic features that distinguish a high
grade intraductal pancreatic mucinous neoplasm (IPMN) from a low grade neoplasm?
• Identify key terms: intraductal papillary mucinous neoplasm [tiab]; carcinoma, pancreatic ductal [mh]; cytodiagnosis [mh]; cytology [tiab] OR cytologic [tiab]
• Combine concepts
REFINING RESULTS
What do I do when I get …
Too many results?
• Use MeSH and/or subheadings to refine concept definition
• Restrict keywords to title and/or abstract
• Use limits – date, publication type, etc.
• Use special features – clinical queries or topic-specific queries
Not enough results?
• Remove limits• Add keywords or MeSH
terms to improve recall• Use related citations to
identify other relevant concepts
Search construction: Techniques• Limits – use sparingly (language, age, publication type)
Clipboard
Clipboard
MANAGING RESULTSMyNCBI
Set up account• Click myNCBI in upper right corner• Click ‘Register for an account’• Complete registration screen (including email address)• Confirm email sent to account
My NCBI homepage
MANAGE RESULTSEmail, export to EndNote, save as Collection
SAVE SEARCH, SET SEARCH ALERTSSave search URL, save search to MyNCBI
Save search via link
Save search from history
SET PREFERENCES AND FILTERSCustomize PubMed
Setting preferences
PubMed filters
