So, once you've made it to the search page of a database, what do you need to know to start searching? This section provides some generic information. A number of databases have some of their own advanced individual features, but this section should get you going quite well.

Monash University provides a useful generic guide called how to develop a search strategy and Sheffield University provides a detailed step by step tutorial on searching.

Medical databases use a concept called Boolean logic. This uses three "operators" - AND, OR and NOT. These are written in upper case.

Parentheses may be used to group words. For example:

Children AND (hearing OR auditory)

This will retrieve articles with one or both of the words "hearing" or "auditory" and the word "children".

Using the word "children" may miss a number of potentially useful articles, for example suppose the authors have used "child", "childhood" or even "child's" because of the grammatical way in which it appeared in the title or text. This is where truncation and the "wild card" come in. Truncate "Children" to "child" and add a "*", viz:

"child*" - this will retrieve child, children, childhood and child's.

So a better search strategy would be:

Child* AND (hearing OR auditory)

'How to read a paper: the Medline Database' is a well written introduction to using Medline.

The University of Florida provides a good interactive PubMed tutorial which is aimed specifically at the freely available PubMed Version of Medline. This will provide you with additional techniques for improving your search.

When learning to search, the meta-search engine SUMsearch is quite useful as it provides questions and prompts when you enter your search strategy.

There can be real difficulty trying to sift out information that is relevant to clinical practice when searching large databases such as Medline. The PubMed version of Medline as a really neat feature called clinical queries. This has pre-designed filters that take out a lot of the hard work of searching effectively. You can search specifically for clinically relevant articles related to therapy, diagnosis, aetiology or prognosis with one simple "click".

For further information on filters for Medline and other databases look at either Finding the Best Clinical Literature on the University of Illinois at Chicago's Evidence Based Medicine website or the Critical Appraisal Skills Program on the Public Health Resource website.

ADEPT at the University of Sheffield provides a detailed look at filters and has some exercises with which to practise searching.