Systematic Reviews

The definition of ‘truncation’ is to shorten or cut-off at the end. Truncation is used in database searches to ensure the retrieval of all possible variations of a search term.  All databases allow truncation, but the symbols used may vary, so it is best to check the database help for details.

Databases usually allow words to be truncated either at the end, or internally:

• Truncating a word at the end ensures that all variations of the word, beginning with a specific root, will be retrieved. This is particularly useful for retrieving singular and plural versions of words.

Be careful not to truncate terms too early, or you may retrieve a high number of irrelevant documents.

Most databases use an asterisk (*) to find alternate endings for terms. For example: therap* will retrieve therapy, therapies, therapists, therapeutic, therapeutical, etc.

• Truncating a word internally ensures that any variations of spelling of a word can be retrieved. For example, pediatrics or paedetrics

Internal truncation is available in some databases, allowing you to search for alternate spellings of words – extremely useful when searching for American and English spellings of words.

For example, using the OVID databases (MEDLINE, HAPI, JBI etc), a question mark included within a word can designate zero or one character in that place: colo?r will retrieve colour or color