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Grey Literature: Home

This resource guide is designed to help users find unpublished, non-commercial, hard-to-find information known as Grey Literature.


Grey literature is the unpublished, non-commercial, hard-to-find information that organizations such as professional associations, research institutes, departments or universities, think tanks, and government departments produce. Finding grey literature can be a challenging process, so please contact the MCW Libraries with any questions.


What is Grey Literature?

Grey literature is the unpublished information that organizations such as professional associations, research institutes, think tanks, and government departments produce.

It can be invaluable to your research, as it it is part of the overall evidence base and functions as an alternative source that may be used to overcome possible bias presented by published information or information from more traditional outlets.

Grey Literature is commonly found in the following formats:

  • Government and non-governmental organization reports and documents
  • Conference proceedings
  • Theses
  • Bibliographies
  • Surveys. Interviews
  • White papers
  • Clinical trials
  • Pamphlets, newsletters, bulletins, fact sheets
  • Non-traditional communication and media (blogs, podcasts, e-mail, social media)

GreyNet International has a comprehensive list of document types.

Critical Appraisal

Once information from grey literature sources is obtained, an additional challenge for the researcher is to determine the quality of that information.

AACODS Checklist

Jess Tyndall, Medical Librarian at Flinders University, developed the AACODS checklist (Authority, Accuracy, Coverage, Objectivity, Date, Significance) as an evaluation and Critical Appraisal Tool specifically for use with grey literature sources.1













Follow this link to the comprehensive AACODS checklist tool.
1. Tyndall, J. AACODS Checklist.  Flinders University, 2010. Available from

Grey Matters: a practical tool for searching health-related grey literature (CADTH)
From CADTH, the Canadian Agency for Drugs and Technologies in Health, Grey Matters is a practical tool for searching health-related grey literature. The MS Word document covers a grey literature checklist, including national and international health technology assessment (HTA) web sites, drug and device regulatory agencies, clinical trial registries, health economics resources, Canadian health prevalence or incidence databases, and drug formulary web sites.

Agency for Healthcare Research & Quality (AHRQ)
Methods Guide – Chapter: Finding Grey Literature Evidence and Assessing for Outcome and Analysis Reporting Biases When Comparing Medical Interventions: AHRQ and the Effective Health Care Program. Effective Health Care Program, Agency for Healthcare Research and Quality, Rockville, MD.   


CINAHL Search Tip:
In CINAHL, users can scroll down on the main search page and, in the Publication Type drop-down, select "Doctoral Dissertation" or "Proceedings."

Scopus Search Tip: Users should run their initial search e.g.- "negative pressure wound" and then, under "Refine results" on the left margin select different "Document types" like "Conference Paper," "Conference Review."

Web of Science Search Tip:
Users should run their initial search e.g.-"negative pressure wound" and then, along the left-hand margin select "Document Types" such as "Meeting Abstracts", "Proceedings Papers."

Agency for Healthcare Research & Quality (AHRQ)
The Agency for Healthcare Research and Quality (AHRQ)'s publications offer practical information to help a variety of health care organizations, providers
Bielefeld Academic Search Engine (BASE)
A search engine primarily for academic open access web resources, operated by Bielefeld University Library (Germany). Initial search results are organized by relevancy with tools to further refine searches.
Centre for Reviews & Dissemination (CRD)
Conducts systematic reviews and research into health and social care interventions.
Scientific literature computer and information sciences.
Clinical Medical and Health Research
A repository of non-peer reviewed, not-yet-published original research closed to new submissions in 2005, now located on PubMed Central.
Preprints, book chapters, published and unpublished papers in psychology, neuroscience, linguistics, and other sciences.
Directory of Open Access Journals (DOAJ)
Lists open access scientific & scholarly journals, all of which are quality controlled. Browse by title or subject.
Grey Literature Report
NYAM's bi-monthly report identifying new publications in health sciences grey literature has ceased publication, but materials from 1999 to 2016 are still available.
GreyNet International
An open access repository of 700,000 bibliographical references of grey literature produced in Europe.
GreySource Index
Provides categorized examples of web based grey literature.
Healthy People 2030
Maintained by the Office of disease Prevention and Health Promotion (DPHP), users can access free, reliable health statistics. 
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 (such as PubMed &
A federated search engine for searching multiple federal government databases.
NASA Technical Reports Server
Aerospace information and technical literature from NASA.
National Center for Health Statistics (NCHS) (CDC)
The National Center for Health Statistics (NCHS) collects, analyzes, and disseminates timely, relevant, and accurate health data and statistics.
National Library of Energy
Search the entire suite of Dept. of Energy science resources, including R&D, green energy, technology transfer, and patents. Includes Science Accelerator.
Search portfolios of research funded by the National Institutes of Health.
OSTI.GOV (Office of Scientific & Technical Information, Dept of Energy)
The primary search tool for Department of Energy (DOE) funded science, technology, & engineering R&D results. It combines the search structure of OSTI’s previous search tool, SciTech Connect, with information about OSTI and the tools & services it provides to users across the DOE complex & to the public.
Public Access Gateway for Energy & Science (PAGES)
The Public Access Gateway for Energy & Science or PAGES (formerly E-PRINT Network) provides access to journal articles & peer-reviewed manuscripts that resulted from Dept of Energy funding.

Reports & Reviews

AHRQ Technology Assessments
Agency for Healthcare Research and Quality Technology Assessment Program. Provides tech assessments.
AHRQ: Evidence-based Practice Center (EPC) Reports
Completed reports & technology assessments.
AHRQ: Effective Health Care Reports
In English and Spanish.
California Technology Assessment Forum
Reviews objective evidence reports and develops recommendations for how stakeholders can apply evidence to improve the quality and value of health care.
Centre for Reviews & Dissemination (CRD)
Conducts systematic reviews and research into health and social care interventions.
Defense Advanced Research Projects Agency (DARPA)
Projects include Med-Devices, Neuroscience, & more. Search by tag.
Drug Effectiveness Review Project (DERP)
From the Oregon Health & Science University.
EPPI-Centre Databases
The Evidence for Policy and Practice Information and Co-ordinating Centre conducts systematic reviews across a range of topics.
Health Services/Technology Assessment Text (HTSAT)
Full text documents of a variety of reports. Also search other titles in the Bookshelf.
Health Technology Assessment International (HTAi)
Search using the Interest Sub-groups menu.
HSRR (Health Services and Sciences Research Resources)
*Note that this is an archived resource with Last Archive capture date of 8/20/2021. Research datasets & instruments used in research in the health services. From the National Information Center on Health Services Research and Health Care Technology (NICHSR).
ICSI Health Care Guidelines
Browse documents by type in the drop-down list
Kaiser Family Foundation
Browse reports and data by topic.

Clinical Trials & Registered Research

Open Trials
Open Trials is an open, online database of information about the world’s clinical research trials, designed to increase transparency and improve access to research.
An international initiative to have all past & present clinical trials registered & their full methods & summary results reported.
CenterWatch Clinical Trials
Online database of industry-sponsored global clinical trials actively seeking study volunteers.
Provides information on U.S. government & privately funded clinical trials, including trials no longer recruiting patients.
Tracks switched outcomes in clinical trials.
E.U. Clinical Trials Register
Information about clinical trials in the E.U. from the confidential, E.U. clinical trial database EudraCT.
GSK Clinical Study Register
Provides data from clinical studies sponsored by Glaxo-Smith-Kline.
Interagency Pain Research Portfolio (IPRP)
Provides information about pain research & training activities supported by the federal government.
International Standard Randomised Controlled Trial Number Register
National Research Register (NRR) Archive
Includes UK research from early 2000 through September 2007, provided by the National Institute for Health Research in the UK.
U.K. Clinical Research Network
Comprised of studies belonging to the UK.
WHO International Clinical Trials Registry Platform

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