Comprehensive Searching in the Social Sciences

In order to be as thorough and repeatable as possible, you should not only conduct several keyword searches and several subject searches, but also several searches where you combine the two. According to the Cochrane Handbook for Systematic Reviews of Interventions, "In order to identify as many relevant records as possible searches should comprise a combination of subject terms selected from the controlled vocabulary or thesaurus (‘exploded' where appropriate) with a wide range of free-text terms (Higgins & Green, 2008, p. 131)."

Not only does a combination search allow us to search synonyms of controlled vocabulary terms along with those subject terms, but it also allows us to search within subject categories in databases where the controlled vocabulary is more broad, such as in Web of Science.

Higgins, J. P. T., & Green, S. (2008). Cochrane Handbook for Systematic Reviews of Interventions. Hoboken, UNITED KINGDOM: John Wiley & Sons, Incorporated. Retrieved from http://ebookcentral.proquest.com/lib/utah/detail.action?docID=366838

Higgins, J. P. T., & Green, S. (2008). Cochrane Handbook for Systematic Reviews of Interventions. Hoboken, UNITED KINGDOM: John Wiley & Sons, Incorporated. Retrieved from http://ebookcentral.proquest.com/lib/utah/detail.action?docID=366838, p. 133

When building your search strings, you can either use the search fields with drop-down menus to select fields and Boolean operators, allowing the database to construct your string for you, or you can manually construct your string by typing out field codes and operators. Either way, it is good to be familiar with methods such as nesting and truncation, demonstrated in the Search Strategies box on this page.

Let's continue with our topic of the effects of bullying on minority high school students. The field codes and subject terms used in this example are not taken from any one particular database or thesaurus and are rather used to illustrate the method.

From our topic, we can possibly use the keywords "bullying" and "minority high school students." From there, we can develop synonyms such as "harassment," "hazing," "intimidation," or "abuse" for "bullying" and "diverse high school students" or "marginalized high school students" for "minority high school students." We can also use truncation to retrieve different forms of a word.

To build a string with just these keywords, we need to use OR operators to combine our synonyms, and further combine those strings with AND:

("bully*" OR "harass*" OR "haz*" OR "intimidat*" or "abuse") AND ("minority high school students" OR "diverse high school students" OR "marginalized high school students")

From here, we can start adding in our controlled terms as more synonyms; let's say our controlled terms are Bullying and Minority high school students.

((SU=Bullying) OR ("bully*" OR "harass*" OR "haz*" OR "intimidat*" or "abuse")) AND ((SU=Minority high school students) OR ("minority high school students" OR "diverse high school students" OR "marginalized high school students"))

Notice how we left in our subject terms as keywords. This is to ensure that those terms can be found anywhere in the record instead of just in the subject field.

If we want to instead search within a particular controlled term, like we would need to do in Scopus or Web of Science, we can again use the AND operator:

SU=Psychology, Applied AND (("bully*" OR "harass*" OR "haz*" OR "intimidat*" or "abuse") AND ("minority high school students" OR "diverse high school students" OR "marginalized high school students"))

It is important to note that searching is a recursive and often frustrating process: you will need to see what works and what fails and adjust when needed.

Boolean Operators are used to connect and define the relationship between your search terms.  When searching electronic databases, you can use Boolean Operators to either broaden or narrow your search results.  The three Boolean Operators are AND, OR and NOT.

Boolean Operators

Boolean operators are simple words (AND, OR and NOT) used as conjunctions to combine or exclude keywords in a search, resulting in more focused search results.

OR

• Broadens or expands your search
• Is used to retrieve like terms or synonyms
• Finds all items with either teenager OR adolescent
• In set theory and math, "union" is inclusive "OR".
  "OR" = teenager U adolescent

AND

• Narrows or limits your search
• Used to retrieve unrelated terms
• Finds items with both diet and children
• In set theory and math, "intersection" is "AND".
  "AND" = diet ∩ children

NOT

• Narrows or limits your search
• Finds the term "spider" not "monkey"
• Use the NOT operator with caution
• May eliminate relevant records

Note:
AND is the default or implied operator in Usearch, Google, Scopus, PubMed, EBSCOhost, and most search interfaces. 
"ecotourism sustainable" is the same as "ecotourism AND sustainable"

In Usearch, EBSCOhost, SCOPUS, and PubMed, Boolean operators (AND, OR, NOT) must be entered in upper case.

Phrase Searching

Phrase searching is using quotations.

For instance:

"international olympic committee"
"Utah tennis"

It finds the exact phrase, and items with words in the order typed.  One exception is Scopus.  Scopus uses curly brackets or braces for {exact phrase} searching.  In Scopus, quotes are used for "loose/approximate phrase" searching.

Truncation Stemming

Truncation or stemming is using an asterisk *.  It is also known as a wildcard.  Truncation is a symbol that retrieves all the suffixes or endings of a word.

For instance:

school*             retrieves school, schools, schooling, schooled, etc.
latin*                 retrieves latina, latino, latinx, latinos, latinas, latin, latinization, etc.

Note:
In the Library of Congress, % (percent sign) is a single character wildcard and ? (question mark) is truncation for multiple characters.

Nesting

Nesting is commonly used when combining more than one Boolean operator (OR, AND).  Most search interfaces search left to right.  Using parentheses in a search changes the order of operation.

For instance:

(moral* OR ethic*) AND (assisted suicide OR euthanasia)

(ski OR skis OR skiing OR snowboard*) AND video*

Proximity or Adjacency Operators

Proximity operators allow you to find one word within a certain distance of another.

With (w), Near (n), Next (n), or Pre (p) are common proximity operators.

Note:
Read the database help to see if proximity operators can be used in your searches.

Thanks to Alfred Mowdood for authoring these instructions.