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What is Grey Literature?
The Fourth International Conference on Grey Literature (GL '99) in Washington, DC, in October 1999 defined grey literature as follows: "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." - New York Academy of Medicine
Why Grey Literature?
From The Institute of Medicine:
Take action to address potentially biased reporting of research results.
Search grey literature databases, clinical trial registries, and other sources of unpublished information about studies
Grey Lit Sources:
- Institutional Repositories
- Clinical Trial Registries
- Drug Registries
- Organizational Websites
- Government (federal, state, and local)
- International Organizations
ClinicalTrials.gov is a registry and results database of publicly and privately supported clinical studies of human participants conducted around the world. ClinicalTrials.gov also provides links to related citations in the PubMed.gov database
Formerly Virginia Henderson Global Nursing e-Repository. A global digital service that collects, preserves and shares nursing research and evidence-based practice materials.
An online searchable collection of over 3300 books, reports, databases, and other scholarly literature in biology, medicine, and the life sciences. Includes government reports deposited from: National Academies Press (NAP), Agency for Healthcare Research and Quality (AHRQ), Canadian Agency for Drugs and Technologies in Health (CADTH), and World Health Organization (WHO)
OAIster: Find the Pearls
OAIster is a union catalog of millions of records representing open archive resources that was built by harvesting from open archive collections worldwide using the Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH). OAIster records are freely available through WorldCat.org.
Additional Grey Literature Resources
Additional databases that may be available through an institution
- Healthcare Management Information Consortium (HMIC)
- ProQuest Dissertations & Theses A&I (UIC)
This resource is a directory of over 2600 academic open access repositories. The directory is run by the Centre for Research communications (CRC), University of Nottingham. Links to various resources are listed on the Country and Organizations access page. Also available is a Search Repository Contents page. These search results include links to the full-text documents.
Bielefeld Academic Search Engine (BASE)
BASE is a search engine primarily for academic open access web resources. A resource of over 2600 academic open access repositories, BASE is operated by Bielefeld University Library (Germany). Initial search results are organized by relevancy with tools to further refine searches. The search results citations include links to the full-text documents.
This is a global science gateway comprised of national and international scientific databases and portals that, for a keyword search, examines 99 sources. A multilateral partnership, the project was developed and is maintained by the Office of Scientific and Technical Information, Department of Energy (USA). Search results are organized into papers, multimedia and data sections. In the Topics section, one of the options is Full Text Articles. Note: search results for this gateway include links to commercially produced material that may be available from the various R4L program portals.
A free, publicly available deep web search engine that uses advanced federated search technology to return high quality results by submitting your search query – in real-time – to other well respected search engines. Mednar then collates, ranks and drops duplicates of the results.
Health Sciences Online (HSO)
Search and browse any health sciences topic from over 50,000 courses, references, guidelines, and other learning resources. Materials are selected from accredited educational sources including universities, governments, and professional societies, by HSO staff.
National Technical Information Service (NTIS)
Provides access to the results of both US and non-US government-sponsored research and can provide the full text of the technical report for most of the results retrieved
Biomedical and life sciences search engine
Other Library Guides on Gray Literature
UIC: Public Health/Grey Literature
Topics: Introduction, Dissertations & Theses, Reports & Working Papers, Government Documents, Databooks, Collaborative Resources
Duke University: Grey Literature
Topics: Abstract and Conferences, Regulatory and Government, Pharma Data and Trial Registries, Repositories and Reports, International
LA Trobe University: Grey Literature for Health Sciences
Topics: Theses, Conference Papers, Clinical Trials and Practice Guidelines, Australian Government Sources, General Sources and Directories
University of Michigan Library: Grey Literature
Topics: Databases, Conferences, Clinical Trials/Regulatory Data, Reports and Reviews
University of Illinois at Urbana-Champaign: Gray Literature
Topics: Biomedicine, Evidence-Based Practice, Health Policy, Public Health, Cross Disciplinary, Organizations, Data
University of New Mexico: Gray literature 101: Introduction
Topics: More about gray lit, Resources, Search help, Databases and Web Resources
Weber State University: Grey Literature
Topics: Technical Reports, Arts and Humanities, Health Sciences, Sciences, Social Sciences, Education