Grey literature is usually not as well indexed as traditional research. Developing a search for grey literature shares some similarities with traditional database searching, such as the use of keywords and search operators. However, tools such as search engines often have limited search functionality and may require simpler search queries with an increased emphasis on using filters/ limiters or on screening results for relevance.
Key sources for grey literature vary depending on the type, and include specialised databases, repositories and search engines. Artificial intelligence (AI) search engines are increasingly valuable in identifying grey literature.
Search engines crawl the web, index websites, rank them, and display results matching user queries. Algorithms consider prior search activity, so results may vary for different users. While searches aren't replicable, reporting the search can aid transparency. In general, keep searches simple.
Semantic search tools are designed as conversational search tools. They work best with natural language questions instead of keyword-based searches. It’s important to note that searches with these tools are not replicable and may not be suitable for systematic reviews. They are also subject to bias and all output should be critically evaluated
The focus of specialist databases and repositories are often maintained by government, academic or not-for-profit organisations. They often provide help or instructional material on their search functions. In general, keep searches simple with a few key search terms and simple search operators.
Further details on specialised search sources for different types of grey literature can be found in other sections of this guide.
Where grey literature material has been retired, removed or is otherwise no longer accessible, you can conduct a search using the Internet Archive Wayback Machine for previous versions of websites.
The Wayback Machine is unavailable on Deakin computers but is accessible via personal devices.