Your search needs to be as exhaustive as possible, and include published and (in most cases) unpublished sources.
Use more than one source, and don't rely on Google or Google Scholar. You can construct much more structured searches in bibliographic databases such as ERIC and PsycInfo. Most databases have a controlled vocabulary feature (standardised subject headings or thesaurus terms) which can help ensure you capture all the relevant studies; for example, MEDLINE, CENTRAL and PubMed use the same headings, which are called MeSH (Medical Subject Headings). Not all do - Web of Science and JSTOR don't allow you to search within subject headings like these, although you can of course search for subjects in them.
Your Subject Librarian will be happy to help you identify possible places to search.
When you're just starting out you might want to do a quick scoping search to evaluate the amount of literature on a topic. To do this you could start with the Library's catalogue, Stella Search, which includes records of papers taken from many of our subscribed databases. HOWEVER, this would not be an appropriate resource to use as part of the review itself, and should only be used as a first step. Searches for the review itself should always be run directly in the appropriate databases.
You should also do scoping searches to identify relevant databases (see below). These preliminary searches will also help you identify relevant keywords to use.
Start with identifying the key databases covering your field by taking a look at the Databases section on appropriate subject guide(s), or by going directly to our Databases AZ. Your Subject Librarian can also advise on the best ones to search.
The Library will have access to the vast majority of relevant databases. You may also need to extend your search to databases not available at Trinity, for example a funding provider may stipulate you use the Ovid version of PsycInfo, rather than the Ebsco version. In this case you may need to arrange a visit to an institution which subscribes to it (ask for a Letter of Introduction from your Subject Librarian), or recruit a team member with access.
If you are unsure which databases to use, try looking at existing reviews in the same field for details of which databases they searched (see the box on the left for some sources).
Once you have identified the key journals you may want to browse through their tables of contents going back a few years, or do a keyword search directly on the journal site, to make sure you haven't missed anything. Many reviews will state that they hand-searched two or three of the top journals in the area. However, if you find that you are discovering lots of new, relevant articles in this way that should be a red flag that something is not working with your search strategy - it should pick up the vast majority of relevant articles. If this is the case, talk to your Subject Librarian to see if we can find out what is going wrong.
In addition to identifying published resources you will need a strategy for finding grey literature. This is usually research material that is not available via the usual published sources. This can include:
These can be identified by running internet searches, and consulting key websites of relevant organisations.
Following citation trails will help you find more resources for a particular topic of discussion. It will also allow you to situate a particular work in its greater academic context, and understand how the discussion around it has progressed. By tracking the citation forward (identifying who has cited the article), you can see how previous scholars have responded to the work, including confirmation of research findings, disagreements, corrections, criticisms and further discussions. This, in turn, will help you identify current trends in the research community and other areas for further exploration.
Google Scholar, along with many of the Library's research databases (most notably, the two big multidisciplinary databases, Scopus and Web of Science), allow for tracking citations forward.
If you are are undertaking a systematic review, citation tracking is often a documented part of the study, normally undertaken near the end of the review in the studies being "extracted".
Example: Google Scholar
Example: Web of Science
You will then see a list of articles that match your search. Click on the relevant title to get more details such as the abstract. Under Citation Network is a link to other articles within Web of Science that cite this article.