Systematic Literature Searches
Sources to search
When you have created your search strategy you then need to select which databases, you want to search in. There are differences in the various types of search tool and database. As a starting point it is always best to search in several databases that can supplement each other:
- Bibliographical databases: record "everything" about a topic, a geographical area, a person, institution, etc.
- Library databases: reflect what can be physically and electronically found via one or more libraries.
- Journal databases: consist of journals from a specific supplier.
- Specialised databases: e.g. databases that register grey literature, conference papers, OA repositories, radio/tv, GPS data, compositions, artefacts, etc.
The strength of the bibliographic databases is their focus on the subject area, rather than where it is physically located and what form it may have. You probably already know important databases within your subject area, but it can be a good idea to check the coverage provided by the individual databases, so that you are aware if the database has a bias towards, for example, American literature over European, or journal literature over monographs? Therefore check, for example:
- Are there limitations in relation to the geographical area or languages covered?
- Does the database go far enough back in time for your purposes?
- How quickly is the database updated with regard to the registration of the most recent literature?
- Does the database cover all the publication types, you need?
In addition to searching databases, consider trying the following approaches to identifying studies:
- Looking for grey (unpublished) literature
- Checking reference lists of relevant articles for other relevant studies (snowballing)
- Google searching using the Google Advanced search option for better results. Limit to filetype PDF to restrict results to documents, reports etc. rather than blogs and websites.
- Handsearching a select range of specialist journals and conference proceedings closely aligned with your topic of interest.
- Identifying experts in the field and contacting them for information about other studies or data.
- Some journal titles are not indexed in the major databases
- Some sections of journals (e.g. meeting abstracts) are not indexed
- Indexing is a fallible process. Citations can have the wrong subject headings assigned or relevant subject headings can be missed rendering a citation difficult to find via an electronic database search.
- To avoid relying completely on your search strategy.
For more information on specific journals: