Online research sources for scientific and technical topics have a long history. But have you considered grey literature sources that can be found on a number of free websites and as part of subscription services? Excellent sources of information, they tend to be underutilized by many researchers. However, the range of information resources available and the challenges of using multiple search interfaces can make finding relevant results very frustrating. This article attempts to demystify this process by providing an overview of the major sci/tech grey literature search tools, databases, and other sources.
What do I mean by grey literature? Many definitions exist. Most could be excellent cures for insomnia. In terms of its clarity and brevity, one of my personal favorites was offered in 1999 at the Fourth International Conference on Grey Literature (greylit.org/about): “That which is produced on all levels of government, academics, business and industry in print and electronic formats, but which is not controlled by commercial publishers.”
The site goes on to quote from a 1990 article in the Bulletin of the Medical Library Association, “The Use of Grey Literature in Health Sciences: A Preliminary Survey,” by V. Alberani, PDC Pietrangeli, and AMR Mazza:
In general, grey literature publications are non-conventional, fugitive, and sometimes ephemeral publications. They may include, but are not limited to the following types of materials: reports (pre-prints, preliminary progress and advanced reports, technical reports, statistical reports, memoranda, state-of-the art reports, market research reports, etc.), theses, conference proceedings, technical specifications and standards, non-commercial translations, bibliographies, technical and commercial documentation, and official documents not published commercially (primarily government reports and documents).
Boiled down to its most basic elements, grey literature is everything but peer-reviewed journals and academically or commercially published books.
What does that leave? How about a huge cluttered mess that includes a large number of different formats? In addition to the formats described at the GreyLit site, grey literature includes patents, datasets, and white papers. It is important to remember that the number and types of formats will evolve across time, as they have since the 1990 article and 1999 conference, given the rapid changes occurring in publishing and electronic media.
WHICH SHADE TO PICK
When organizing a presentation on a topic that is not well-defined, as I did for a recent webinar on scientific/technical grey literature that was the forerunner of this article, I had to make some seemingly arbitrary choices about what to discuss. Both the health and social sciences have some very well-developed, specialized grey literature resources that I do not cover in this article. Instead, I focus on major and/or well-known resources, although I also mention a few more specialized items.
In addition, a few resources in this area are so unique, such as patents, that they have their own set of search tools, again beyond the scope of this article. Finally, I concentrate on open access or low-cost resources since many people find themselves working in cost-constrained or open access environments. And, although there are certainly at least 50 sources for finding grey literature, I’ve been more selective.
Generally speaking, organizations that produce science and technical grey literature have more flexibility and a slightly different focus than academic journal and book publishers. Some types of information can be found more quickly in grey literature, such as general overviews, recent bibliographies, sources of statistics, and leading-edge information. In the health sciences, where a priority is put on cutting-edge research, the newest information is frequently found in grey literature resources. As a result, these sources are part of the evidenced-based systematic review process.
The very nature of sci/tech grey literature also imposes some problems. While many resources in this area go through some type of peer-reviewed or quality-control process, you need to take a critical look at the reliability of the information. Who is publishing the work? Does the publisher have a particular point of view?