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Grey Literature in the Health Sciences: Evaluating Grey Lit

Describes what grey literature is, why it is important to search it, how to focus your search, which resources are available to search, and how to evaluate grey literature. License: Creative Commons Attribution-NonCommercial Share Alike 4.0 International.

Guide Contents

How to evaluate grey literature - the AACOGS checklist

The  AACODS checklist was created by Jess Tyndall to evaluate and enable critical appraisal of grey literature. This checklist has the flexibility to be applied to a number of grey literature resources.

AACODS (Authority, Accuracy, Coverage, Objectivity, Date, Significance)

  • Authority: Who is responsible for the content and are they credible?
  • Accuracy: Is the document supported by credible, authoritative sources?
  • Coverage: Does the document clearly state parameters that define their content coverage?
  • Objectivity: Is there bias? Is it easily detected?
  • Date: Can you find the date? For the content to inform your research it must have a date to confirm relevance
  • Significance: Does the document add something unique to the research?

Source Guide: McMaster University

AGREE Tools - Guidelines Appraisal

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We gratefully acknowledge that the content of this guide (including links, descriptions, and selected categories) is reused/remixed from the following guides and sources under a Creative Commons Attribution NonCommerical ShareAlike 4.0 International License.

Confirmation of the Creative Commons status of the entire USC guide was also sought and received in writing from the USC Guide Author Karin Saric on 11 July 2019. Reuse permission was granted provided attribution is given.

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