2. Literature Search

Once you have defined your search question, you are ready to start the literature search.

First, make sure the work hasn't already been done! By looking for previous reviews on your subject you can save a lot of time and frustration in the long run.

The Cochrane Library has a large database of independent high quality systematic reviews. From here, you can search for both completed and proposed reviews as well as the The Cochrane Central Register of Controlled Trials (CENTRAL) database of randomised controlled trials which had 470,000 registered RCTs, and other databases.

If there are no systematic reviews on your subject, you will now need to start searching the literature for relevant articles for your project. Should the work be done already, a link to the appropriate website or a short summary would be welcomed.

The aim of the literature search is to theoretically get ALL the articles relevant to your subject area. The most important thing is to find all the relevant articles without being too sensitive so that you have to wade through hundreds of irrelevant articles to find them.

PubMed is a free medical database of over 16 million articles. It incorporates Medline and OldMedline.

For the purposes of the WHO reviews, the search strategy utilises the ‘Clinical Queries’ framework available in PubMed. This enables systematic searches of therapeutic, diagnostic, etiologic or prognostic questions on disease state or condition. This technique has been well validated, is reproducible, and is generally available in developing countries. It is possible to use broad or narrow (sensitive or specific) sub-searches.

Remember to keep records of all your searches: your strategies, the number of hits you received and the number of relevant articles identified.

» Part 3: Accessing Relevant Articles

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