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Introduction to Literature Search

This guide is intended to provide you with the basic skills necessary to search for literature. The skills are presented broadly and can be applied across all databases.

What is Grey Literature?

grey literature examples

Grey literature is scholarly-like literature published through non-commercial channels: organizations, schools, government agencies, and others.

 

It provides authoritative information beyond commercial publications like books and journals.

 

It is created and distributed in order to disseminate knowledge (ideas, facts, opinions) rather than to sell for a profit (Mackenzie Owen, 1997).

 

Grey does not imply any qualification, it is merely a characterization of the distribution mode (Mackenzie Owen, 1997).

Mackenzie Owen, J. (1997, November 13-14). The expanding horizon of grey literature [Paper presentation]. Third International Conference on Grey Literature: Perspectives on the Design and Transfer of Scientific and Technical Information, Luxembourg. http://www.opengrey.eu/data/69/79/67/GL3_Mackenzie_Owen_1998_Conference_Preprint.pdf

Depth & Breadth

Deep subject analysis (as from theses and dissertations) and broad overviews (as from government reports)

💡 What scope do I want and how much time do I have to engage with it?

Timeliness

Faster publication than through traditional channels; receive and engage with information even 12-18 months sooner

💡 How recent does the information I want need to be?

Flexibility

Authors can issue quicker updates to their grey-literature publications than via commercial publishers

💡 Will more dynamic sources aid my research?

Accessibility

General public can often access grey literature freely online and via open access

💡 How important is it that this information be universally accessible?

Focus

Grey literature often includes studies with negative results, with less bias toward positive results compared to commercial publications

💡 Would I like a fuller understanding of the course of research in the health sciences or just mostly what works?

Location

The cosmopolitan distribution across the Internet could require searching in many locations to find needed material (see Where to Find Grey Literature below)

The stability of grey literature on the Internet is not guaranteed; if you find a resource, save it to your personal storage. If you have the URL saved, try to retrieve the previously accessible version using Internet Archive's Wayback Machine

💡 How important is it that the information remain retrievable and exist in a stable format?

Verification, Validation, & Bias

Critically examine any grey literature you find for accuracy, authority, bias, up-to-dateness, and subject coverage (see AAOCC method below or IF I APPLY source evaluation tool)

Ask yourself:

? Who produced the grey literature?

? What makes them the expert?

? Why was it written?

💡 Has the medical community reviewed the source? / Do I want the formal peer review of a commercial journal?

Where to Find Grey Literature

Information on international, publicly and privately supported human clinical studies on a wide range of diseases and conditions.

The EU Clinical Trials Register contains information on interventional clinical trials on medicines conducted in the European Union (EU), or the European Economic Area (EEA) which started after 1 May 2004. ... It is also available on the WHO International Clinical Trials Registry Platform.

The main aim of the WHO ICTRP is to facilitate the prospective registration of the WHO Trial Registration Data Set on all clinical trials, and the public accessibility of that information.

The ISRCTN registry is a primary clinical trial registry recognised by WHO and ICMJE that accepts all clinical research studies ... ISRCTN accepts all studies involving human subjects or populations with outcome measures assessing effects on human health and well-being, including studies in healthcare, social care, education, workplace safety and economic development.

Preprint servers are repositories for papers that are ready for publication, but have not yet been accepted by a journal. Because of this, they are NOT peer reviewed and are considered grey literature. 

Repository founded by Cold Spring Harbor Laboratory, Yale University, and BMJ.

Repository operated by Cold Spring Harbor Laboratory.

Repository maintained and operated by Cornell University.

Repository for preprints devoted to the rapid dissemination of scholarly research in the social sciences and humanities and more.

Preprint Server Directory

Accelerating Scie nce and Publication in Biology (ASAPbio)has compiled a directory of searchable information about preprint platforms relevant to life sciences, biomedical, and clinical research.

Preprint Peer Review Tools

An online journal club

A platform for the crowdsourcing of preprint review

Besides browsing these links, consider WHO CARES about your topic - associations, professional groups, non-profits, etc. (Check the MedlinePlus directory of organizations, arranged by topic or alphabetically.) Go directly to their Web sites and look for a research, publication, or education tab.

🔎 Look under the "Health Topics" drop-down menu and try the Institutional Repository for Information Sharing (IRIS)

The Agency for Healthcare Research and Quality's (AHRQ) mission is to produce evidence to make health care safer, higher quality, more accessible, equitable, and affordable

🔎 Look under the "Research" drop-down menu and check out the Effective Health Care Program

CDC conducts critical science and provides health information that protects our nation against expensive and dangerous health threats, and responds when these arise. ... bringing new knowledge to individual health care and community health

🔎 Start with the "Diseases & Conditions" drop-down menu

KFF (Kaiser Family Foundation) is a non-profit organization focusing on national health issues, as well as the U.S. role in global health policy.

PCORI was established to fund research that can help patients and those who care for them make better-informed decisions about the healthcare choices they face every day

🔎 Check out the "Research & Results" or "Topics" tab

PhRMA represents the country’s leading biopharmaceutical research companies and supports the search for new treatments and cures.

🔎 Start with the "Resources" link in the toolbar

CADTH is an independent, not-for-profit organization responsible for providing health care decision-makers with objective evidence to help make informed decisions about the optimal use of health technologies

🔎 Click the "Reports" or "Resources" links in the toolbar

Institute for Clinical and Economic Review (ICER) is an independent and non-partisan research organization that objectively evaluates the clinical and economic value of prescription drugs, medical tests, and other health care and health care delivery innovations.

🔎 Look at the "Materials Library" linked in the toolbar

Helps countries achieve high-performing health systems by measuring health outcomes & the use of health system resources as well as by analysing policies that improve access, efficiency & quality of health care.

For more than 25 years, the Institute for Healthcare Improvement (IHI) has used improvement science to advance and sustain better outcomes in health and health care across the world.

🔎 Start with the "Resources" tab

The mission of the National Association of County and City Health Officials (NACCHO) is to improve the health of communities by strengthening and advocating for local health departments.

🔎 Look under the "Resources & Research" drop-down menu

Google is great for grey literature! Use the tips in the image below to search more effectively, or use the advanced search page to focus your search more.

Google search tips

WorldWideScience.org is a global science gateway comprised of national and international scientific databases and portals. ... Multilingual WorldWideScience.org provides real-time searching and translation of globally-dispersed multilingual scientific literature.

Think Tank Search searches the websites of institutions that generate public policy research, analysis, and activity. These sites are affiliated with universities, governments, advocacy groups, foundations, and non-governmental organizations.

Mednar is a free, medically-focused deep web search engine

Evaluate your Sources - AAOCC method

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How to Cite Grey Literature

Technical Reports

Generic:

Author, A. A, & Author, B. B. (Year). Title of report (Report No. 1234 [if available]). Publisher Name. https://xxxxxxxxxxx

Example:

National Cancer Institute. (2018). Facing forward: Life after cancer treatment (NIH Publication No. 18-2424). U.S. Department of Health and Human Services, National Institutes of Health. https://www.cancer.gov/publications/patient-education/life-after-treatment.pdf

Other Grey Literature

Generic:

Author, A. A, & Author, B. B. (Year). Title of grey literature [Description of form]. Publisher Name. https://xxxxxxxxxxx

Example:

Centers for Disease Control. (2018). HPV and men [Fact sheet]. https://www.cdc.gov/std/hpv/stdfact-hpv-and-men.htm

Items of note

  • When the publisher is the same entity as the author (which is often the case for grey literature), omit the Publisher element from the citation.
  • If the organization that issued the publication assigned a report number, include that number in parentheses directly after the title.
    • Use the language of the report number (ex: Publication No. 1234, Issue Brief No. 1234, Project No. 1234).
  • A description of form should be included when it will assist the reader in understanding what the source is.
    • There is no pre-defined set of words or formats to use. Some examples might include: Brochure, Press release, or Fact sheet.
  • Grants and press releases use a different date format. Please refer to page 331 in the APA manual for further guidance.

For more information on current and past APA citing rules, please visit the Netter Library APA Citation Help Guide.