Systematic searching
Systematic searching in a review involves methodically applying a search strategy in various information sources like key discipline databases.
The search is built to locate and collect all relevant material on your review topic to help address the research question. The search used in systematic searching is informed by the search terms and search techniques gathered in the preliminary searching. They help to create a search that is exhaustive to minimise publication bias.
Searches should always be documented for transparency and reproducibility. Usually a copy of the final search strategies are included in the review. This allows readers to see what searches were conducted in a review.
Note
It's important to follow guidelines to meet any discipline-specific search requirements.
Balancing sensitivity and precision
A balance with your search must be struck between retrieving all potential studies, even if many are irrelevant (sensitivity) and narrowing results to the most relevant studies, but risking the exclusion of important ones (precision).
An effective search strategy carefully navigates this balance to ensure a review collects a thorough and manageable evidence base.
Translating the search
Different information sources like databases, search engines and repositories use different search tools and techniques. For example, not all databases will have standardised terms or phrases, known as subject headings.
Therefore once the search has been finalised in one information source, such as a key database, it needs to be translated into additional information sources. Elements from your search that typically need to be translated include search syntax and subject headings.
The goal of translating your search into other information sources is to have the search be as close as possible to the original search.
Tip
Consider which search techniques are going to be the most useful and available for your search. Design your search strategy within those parameters.
Testing the search
It is useful to test the effectiveness of the search before finalising it as part of the review protocol.
There are established techniques that utilise comparing your search against known material that meet the review criteria (also known as gold set articles) to verify the effectiveness of the search in retrieving these gold set articles.
Literature review modules
For further information and instructions on preparing and developing a systematic search strategy for a literature review please explore our Module 4: Searching for Literature. and Module 5: Translating search.
Further resources
If you are interesting in further information on this stage of a review, check out the following resources: