Searching Basics

Once you have formulated a good clinical question using the PICO process, the second step in the EBDM process is developing a search strategy to facilitate an effective computerized search of the scientific literature. This allows an efficient search of the best external evidence for answering your question. Finding relevant evidence requires conducting a very focused search of the peer-reviewed professional literature based on the appropriate methodology. When outlining the search strategy it is important to first identify the type of question being asked and then the related research method or study design that is most appropriate.

The PICO Worksheet and Search Strategy Form provides a format to identify key concepts, determine relevant alternative terms and outline inclusion criteria (publication year, gender, age, language and other limits). It also directs you to identify the type of question being asked and the publication type (methodology) related to the question. Selecting the databases and websites to search for valid evidence is the final step in structuring your search strategy.

Online databases and software enable quick access to the literature that have made it easier to locate relevant clinical evidence. Knowing what constitutes the highest levels of evidence, and how to apply evidence-based filters and limits will let you search the literature with maximum efficiency.

Levels of Evidence
Sources regarded as providing stronger evidence include systematic reviews, an individual randomized controlled trial (RCT), and well-designed non-randomized control studies. Links to these resources are found under Scientific Evidence.

Where to search for Evidence
Many of the online resources are free, whereas others require a subscription fee. These resources include: systematic reviews and critically appraised topics; clinical practice guidelines and protocols; article reviews; and drug databases.

One of the free resources is PubMed. Understanding how the PubMed database is structured and its features will help you search the literature with maximum efficiency. The PubMed tutorial walks through all the steps of a search and explains each PubMed feature and tool so that users understand the language, or how information on the database is indexed.

An emerging resource designed specifically to assist clinicians are evidence-based journals that may provide concise and easy-to-read summaries of original and review articles, or of individual articles selected from the biomedical literature. A 1-2 page structured abstract along with an expert commentary highlighting the most relevant and practical information is generally provided.

LINKS to Searching Resources

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