Grey literature searches are commonly included in the research methods sections of literature and systematic reviews as a way of demonstrating a comprehensive search for information and for addressing publication bias. Finding grey literature can be tricky, and the strategy you develop to find the literature can depend on your kind of research. However, a basic search strategy will ensure you search all the relevant places.
It's important to approach your search systematically as grey literature can sometimes be hard to find. Before you start searching, ask yourself:
When developing a search strategy, specify what type of content you want to appear in your search results. Review the Southern Cross University How to Find & Document Grey Literature document.
Try adding these keywords as an additional concept in your search strategy:
The following search process illustrates a search strategy for locating grey literature as part of the overall research process.
Figure illustrates a strategy for locating grey literature as part of the overall research process. Adapted from Duffield, A. et al. (2004).
Once you have performed your grey literature search, good practice is to document the strategy used either as a narrative only, or a narrative that refers to a table of sources, search terms, limiters, search results, excluded results and number of studies included for final consideration.
Grey literature is generated by a wide variety of public and private organisations and can often be disseminated in hundreds of journals and web pages. This makes it challenging to find grey literature, but various tools and techniques are available to streamline your ability to locate it. This can mean a mixed approach of using library databases, search engines such as Google, as well as techniques such as browsing relevant websites and hand-searching of relevant journals.
Watch this short video about using the Advanced Search function in Google.
Handsearching is a critical part of the review process to find materials not found through traditional database searches. It is a manual process to examine and identify further relevant studies. Read more about handsearching in the Systematic and Systematic-Style Review Library Guide.
Information and documents on the internet can disappear at any time! If you find something useful for your research, ensure that you take proper notes to record what you have found. Also, remember to download and save a copy of the resource/s you have found. Use the search plan template below to help you manage your grey literature searches.
Comprehensive searches involve searching multiple databases and search engines. This can often lead to large amounts of data and also duplicated references. To organise your references, remove duplicates, prepare your citations and format your final paper. It is recommended that you use a citation management system such as EndNote.