SEARCH METHODSTypes of Searches Combining

Search Terms (Boolean Searching)

Shelly Warwick, Ph.D.

2013 – Permission is granted to reproduce and edit this work for non-commercial educational use as long as attribution is provided and the edited work is also available under the same terms of license.

After This Unit You should be Able To:State the primary methods of searchingKnow the primary methods of combining

search termsDefine the Boolean operators and the

differences in search results using OR and AND

Be able to use the correct Boolean operator in constructing a search strategy

Search Methods To Be CoveredKeyword • Field• Proximity/adjacency

Keywords

Keyword SearchingFinds word or phrase anywhere in

itemMust match search words or

phrase exactlyFinds words or phrases not

necessarily concepts or subjects

Field Searching

Field SearchingA field is a location or area in which certain

data is located in a database record.Each field in each record in the database

contains like information in the same formatAvailable in organized databases such as

library catalogs or PubMed/MedlineA field search finds the desired terms in the

specified field

Advantages of Field SearchingCan specify in where you want to find the

term you’re searching , e.g. subject, title, abstract.

In a database with a controlled vocabulary good results are usually achieved with searching the subject field

Fields in PubMedAffiliation [AD]Article Identifier [AID]All Fields [ALL]Author [AU]Book [book]Comment CorrectionsCorporate Author [CN]Create Date [CRDT]Completion Date [DCOM]EC/RN Number [RN]Editor [ED]Entrez Date [EDAT]Filter [FILTER]First Author Name [1AU]Full Author Name [FAU]Full Investigator Name [FIR]

Grant Number [GR]

Investigator [IR]ISBN [ISBN]Issue [IP]Journal [TA]Language [LA]Last Author [LASTAU]Location ID [LID]MeSH Date [MHDA]MeSH Major Topic [MAJR]MeSH Subheadings [SH]MeSH Terms [MH]Modification Date [LR]NLM Unique ID [JID]Other Term [OT]OwnerPagination [PG]Personal Name as Subject [PS]

Pharmacological Action [PA]

Place of Publication [PL]PMID [PMID]Publisher [PUBN]Publication Date [DP]Publication Type [PT]Secondary Source ID [SI]Subset [SB]Supplementary Concept[NM]

Text Words [TW]Title [TI]Title/Abstract [TIAB]Transliterated Title [TT]UID [PMID]VersionVolume [VI]

Proximity/Adjacency Searching

Proximity SearchingFinds words within the specified relationship

(adjacent or near) to another word without specifying order so could search for “health” and “literacy” near each other, which would find “health literacy”, “literacy and health”

The ability to do a proximity search, and the codes to do a proximity search varies by database.

Limits/FiltersIn addition to fields, PubMed (and some other

databases such as Ovid) offer Limits or Filters, that allow you to do a search that meets criteria other than the terms entered, or, to display a subset of your search after it has been complete.

Such filters in PubMed Include:Article typeText availability (full text, free full text)Publication datesSpecies (Human/animal)Languages

SexSubjectsJournal categoriesAgesSearch fields

METHODS of combining search terms

Boolean Searching

Combining Search Terms with Boolean Operators

Boolean searching allows you to combine terms (words or concepts) in a search

It uses three words, called operators, to combine terms

The operators are:AND - requires ALL input terms be present

in EVERY item retrieved OR - requires ANY of the terms searched

for be present in items retrievedNOT - which excludes results containing a

specified termSometimes symbols are used instead of the

words, such as + for “and”

Lets Search the Ice Cream Database

Here’s A Venn Diagram of a Chocolate and Vanilla Relationship

VanillaChocolate Vanilla Swirl

Chocolate

Searching for a Single Concept

will yield all information in the brown circle, including the part that overlaps the green circle

Chocolate Vanilla Swirl

Chocolate

VanillaChocolat

e Vanilla Swirl

ChocolateSearching for Chocolate

Searching for a Single Concept

VanillaChocola

te Vanilla Swirl

will yield all the information in the green circle, including the part that overlaps the brown circle

VanillaChocolate Vanilla Swirl

Chocolate

Searching for Vanilla

all the information in both circles - since either chocolate or vanilla is in every area of the diagram.

Using OR

Vanilla

Chocolate Vanilla Swirl

Chocolate

Searching for Chocolate OR Vanilla will yield?

VanillaChocolate Vanilla Swirl

Chocolate

Using AND

only the information in the overlapping area where both chocolate AND vanilla are present, “chocolate vanilla swirl”

VanillaChocolate Vanilla Swirl

Chocolate

Chocolate vanilla swirl

Searching for Chocolate AND Vanilla will yield?

Using NOT

VanillaVanilla

Chocolate Vanilla Swirl

Chocolate

Searching for vanilla NOT chocolate will yield?

all the information in the green circle except in that area that overlaps the brown circle

Using NOT

all the information in the brown circle except that in the area that overlaps the green circle

Chocolate VanillaChocolate Vanilla Swirl

Chocolate

Searching for chocolate NOT vanilla will yield?

Boolean StringsBoolean operators can be used to construct very

complex searches by group search strings as in an algebraic formula

If I want to search for the impact of aspirin or ibuprofen on a 65 year old male with a heart condition and diabetes.

Need to specify that you want article with either aspirin or ibuprofen and that include both cardiovascular disease and diabetes

(Aspirin OR ibuprofen) AND (cardiovascular disease AND diabetes)

[(Aspirin OR ibuprofen) AND (cardiovascular disease AND diabetes)] AND (men and seniors)

Parsing the Boolean StringA parentheses indicates the beginning and

end of a stringBrackets are used to enclose multiple

strings to make them a single term

Search Strings in PubMedPubMed indicates if a search term is a MeSH

term by adding [MeSH] after the term –including for filters

Sample PubMed Search Using The Controlled Vocabulary - MeSH

(("Aspirin"[Mesh] OR "Ibuprofen"[Mesh]) AND "Cardiovascular Diseases"[Mesh]) OR "Diabetes Mellitus, Type 2"[Mesh] AND "aged"[MeSH Terms]

See next page to see the keyword search string in comparison

Sample PubMed Search String From A Keyword Search (("aspirin"[MeSH Terms] OR "aspirin"[All Fields]) OR

("ibuprofen"[MeSH Terms] OR "ibuprofen"[All Fields])) AND (("cardiovascular diseases"[MeSH Terms] OR ("cardiovascular"[All Fields] AND "diseases"[All Fields]) OR "cardiovascular diseases"[All Fields] OR ("cardiovascular"[All Fields] AND "disease"[All Fields]) OR "cardiovascular disease"[All Fields]) AND ("diabetes mellitus"[MeSH Terms] OR ("diabetes"[All Fields] AND "mellitus"[All Fields]) OR "diabetes mellitus"[All Fields] OR "diabetes"[All Fields] OR "diabetes insipidus"[MeSH Terms] OR ("diabetes"[All Fields] AND "insipidus"[All Fields]) OR "diabetes insipidus"[All Fields]))

Comparing Search Results by Method and CombinationSearch Words: health literacyResults by Method:

Keyword/Boolean OR: returns results with items that have either “health” or “literacy” as well as those with “health literacy” any where within the item whether or not the terms are related

Field Search: Returns only those items that have “Health Literacy” within the specified field

Boolean AND: returns results with both “health” and “literacy” as well as those with “health literacy”

Proximity Search – finds items where the words “health” and “literacy” are near each other, no matter the order

Subject Search with Controlled Vocabulary: finds only those items that are indexed as pertaining to health literacy