In academia, researchers traditionally turn to peer-reviewed research publications and academic journals as reliable and verified sources of information. Over the years, however, gray literature has emerged as another category of information in research. In this article, we explain what is gray literature, cover types of gray literature in research, and list some gray literature databases.
What is gray literature in research?
The term ‘gray literature’ comes from the ambiguity surrounding the legitimacy of this information. Gray literature refers to a vast body of information produced by individuals or organizations that is published outside of traditional academic publishing channels. Gray literature is usually not published for commercial gain, not peer reviewed, and not widely disseminated or well represented in indexing databases. Typically self-published or published through non-traditional outlets, gray literature in research includes a wide range of materials, such as research reports, theses, dissertations, conference proceedings, government documents, technical reports, working papers, and preprints.
Why is gray literature considered important today?
Gray literature in research has traditionally been ignored as unverified. However, it is increasingly being considered a legitimate source of information as it provides insights that are unavailable via traditional sources. In fact, researchers looking for information on studies that were rejected by traditional publications because they’ve failed or delivered ambiguous or negative results, may be able to find this in gray literature.
Gray literature in research also refers to information and knowledge presented by independent think tanks, professionals and experts who are not associated with academia. It provides researchers a different perspective on things and adds another layer to the research being conducted. Also, gray literature may be more current and can be communicated more quickly since it does not have to go through formal and established academic editorial processes and publishing channels.
Types of gray literature in research
Here are some of the more common types of gray literature available for researchers:
- Research Reports: These comprehensive documents summarize the findings of a specific research project and are often commissioned by funding agencies, research institutions, or government bodies. Research reports provide valuable insights and data on various fields of study enabling evidence-based decision making. For example, a comprehensive analysis of the impact of climate change on specific ecosystems.
- Technical reports: These are detailed documents that describe research or development projects undertaken by organizations, government agencies, research institutions, or industry organizations. This type of gray literature provides an in-depth analysis, methodologies, and results that may not be available in other sources. Examples of technical reports include those created by agencies such as NASA and consulting agencies like McKinsey & Company.
- Conference proceedings: The collections of research presented at academic or professional conferences, including abstracts, full papers, or summaries of presentations are all part of documents tagged as conference proceedings. This type of gray literature in research enables timely research and gives academics access to latest developments in their field of interest.
- Government documents: This type of gray literature includes reports, policy documents, white papers, and other technical documentation produced by government agencies at the local, state, and national level. These often contain valuable statistical data, legislative proposals, and research findings relevant to public policy and governance, which are critical primary sources of information.
- Theses and dissertations: Formal academic documents produced by students as part of their graduate-level or doctoral studies, theses and dissertations are usually available in university libraries or online databases. While considered part of gray literature in research, the detailed documents contribute original research to a specific discipline and can be excellent sources of information.
- Pre-prints or working papers: These are early versions of unpublished research papers that have not undergone a formal peer review. Preprints allow researchers to disseminate their findings quickly by uploading a complete draft of their manuscript to a public preprint server and getting feedback from the scientific community before formal peer review. There has been a rapid increase in the number of preprints, especially amid the COVID pandemic, but this is still considered a type of gray literature in research.
- Clinical trial data, patents, and technical standards information: While widely considered gray literature in research, information from these key sources can inform and shape current research conducted by organizations.
Common gray literature databases and sources
Listed below are some of the most used repositories and curated collections of grey literature that researchers can tap into:
- Institutional repositories by universities and research institutions are where scholars deposit their theses, dissertations, technical reports, and working papers.
- Government agencies and departments produce a significant amount of gray literature, including reports, policy papers, white papers, and technical documents.
- Research centers and think tanks in specific research areas generate gray literature in the form of research reports, working papers, and policy briefs that provide insights on various topics.
- Academic conferences and symposia often publish conference proceedings, which are an excellent source of recent research and emerging trends within specific disciplines.
- Non-Governmental Organizations (NGOs) engaged in research and advocacy work often produce gray literature to disseminate their findings, raise awareness about specific issues, and influence policy discussions.
- Private companies and industries generate gray literature in the form of technical reports, market research studies, and industry-specific publications that offer insights into advancements, market trends, and industry-specific research.
- Funding agencies or research organizations produce gray literature in the form of reports providing detailed information about the objectives, methodologies, and findings of specific projects.
- Professional associations and societies in various disciplines often publish gray literature, including guidelines, best practice documents, and reports that cater to professionals in respective fields.
- International organizations such as the United Nations (UN), World Bank, and World Health Organization (WHO) produce gray literature in the form of reports, policy papers, and statistical databases covering a wide range of global issues.
- Online repositories and databases collect and curate gray literature, serving as centralized sources of information across research disciplines. These include platforms like OpenGrey, GreySource, and BASE (Bielefeld Academic Search Engine).
Drawbacks of using gray literature in research
While gray literature can offer valuable insights and unique perspectives, it is important to consider its limitations and choose carefully when utilizing it for your research. Here are some drawbacks to using only gray literature in research.
- Quality control: Unlike peer-reviewed publications, gray literature lacks the rigorous review process conducted by experts in the field. As a result, the quality and validity of the information may vary significantly. It is crucial to critically evaluate the credibility and methodology of the source before integrating it into research.
- Accessibility and indexing: Gray literature is often scattered across various sources and may not be easily discoverable through traditional search engines. Researchers might need to utilize specialized databases or contact specific organizations to access this information, which can be time-consuming.
- Limited citations and recognition: Gray literature is generally not accorded the same level of recognition or prestige as peer-reviewed publications. It may be challenging to cite gray literature in research writing, which could potentially affect the credibility and acceptance of the paper.
