Truncation, wildcards, and phrases on Ovid databases
In the Ovid databases you can use the truncation and wildcard symbols to find variations in spelling and variant word endings. The truncation and wildcard symbols can be used anywhere in your search term, except as the first character.
In the Ovid databases, mapping must be turned off for truncation and wildcards to operate properly. If you do not turn off mapping, Ovid attempts to map truncated terms to subject headings, and issues an error message.
The following truncation and wildcard symbols are used in the Ovid databases:
- The truncation symbols (*) or ($) can be used as a substitute for any string of zero or more characters at the end of a word. This symbol can assist in finding both singular and plural forms of a word as well as words spelled in different ways. For example, the search gene* retrieves any record containing "gene", "genes", "genetics", and "generation". By adding a number after $ you can limit the truncation to a maximum number of characters. For example, gene$4 will retrieve "gene", "genetic" and "genetics", but not "generation".
- The wildcard symbol (?) can be used as a substitute for one character or none. It is useful for retrieving records with British and American spelling variations because it finds words whether or not the extra character is present.
For example, the search p?ediatric retrieves records containing "pediatric" or "paediatric"
- The wildcard hash symbol (#) can be used to substitute for exactly one character within a word. For example, the search wom#n retrieves “women” and “woman”. This can be very useful when you are unsure of the spelling of an author’s name.
Be aware that different databases and search engines have different rules and symbols for truncation, wildcards etc. Check the user guide or the ‘help’ section in each database for more information.
Phrase searching on the Ovid databases allows you to search for two or more associated words, such as emergency department, using adjacency searching. For example:
- Searching for emergency ADJ department will find the words emergency and department in the order they are entered with no words in between
- Searching for physical ADJ3 relationship will find the words physical and relationship within TWO words of each other in either direction, and would find many more papers than just searching for the specific phrase “physical relationship”
Using the database adjacency search rule, ADJ(n-1) where n = the number of major words to appear between your words, the following apply:
- ADJ searches for both terms next to each other in the order as typed
- ADJ1 searches for both terms next to each other in either order
- ADJ2 searches for both terms and up to one word in between them
- ADJ3 searches for both terms and up to two words in between them