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:
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. It allows you to search for alternate spellings of words - extremely useful when searching for American and English spellings of words.
Internal truncation is available in some databases such as EMBASE.com. Unfortunately it is not possible in PubMed.
For example, a question mark included within a word can designate zero or one character in that place:
| colo?r will retrieve either colour or color |