Literature Searching: Grey Literature

You can use some advanced features to filter your results. 

Go to Advanced Search: google.com/advanced_search.

Choose a site or domain to restrict your search gov.ie/en/publications/

• If looking for government information you can restrict to gov.ie. If looking for information from Australia and New Zealand you can use to their country domains .au and .nz.
• Other useful domains are .gov for US government, gov.uk for UK government, .edu and .ac.uk for American and British educational institutions 

You can limit Google searches to particular files such as PDFs, PowerPoints etc.

• For example when looking for reports, limit to pdf.
• For datasets use .xls,
• For presentations use .ppt 

Embase contains both published journal articles and unpublished conference proceedings. To limit a search to conference proceedings:

• Undertake a search as normal, searching for each of the concepts and putting them together with AND (see our guide on searching)   
• Use this search string (conference abstract* or conference review or conference paper or conference proceeding).db,pt,su. 
• Use AND to link original search and conference search to limit results to conference proceedings.

• Grey Matters: a practical tool for searching health-related grey literature - Produced by Canada’s Drug Agency (CADTH) this is a list of grey literature sources. It can be searched by title, category, organisation, country and language, or browsed by category.   
• PubGrey - A collection of repositories of unpublished material. These are multidisciplinary and contain healthcare and clinical topics. 

Clinical Practice Guidelines:

• TRIP database - Medical search engine with emphasis on evidence based medicine (EBM). Use the filters on the left to limit results to clinical trials, clinical guidelines etc.
• National Institute for Health and Clinical Excellence (NICE) - NICE produce guidelines, quality standards, evidence summaries and pathways for healthcare in the UK.

Clinical Trial Registries:

• clinicaltrials.gov - Run by the National Library of Medicine this a database of clinical research studies performed both in the USA and globally. 
• International Clinical Trials Registry Platform (ICTRP) - Hosted by the WHO, the ICTRP searches across trials registered in twenty global registries.
• EU clinical trials register - Contains information on clinical trials conducted in the European Union (EU) or outside the EU if they meet certain criteria
• ISRCTN -  Hosted by BioMed Central, the ISRCTN accepts all clinical research studies including both observational and interventional studies.

Systematic Reviews:

• Prospero - Prospero is an international database of prospectively registered systematic reviews in health and social care. Can be used to search for unfinished or unpublished reviews. Also check if planning to undertake a review, to avoid duplication of ongoing research.

Multidisciplinary collections:

• BASE - Operated by Bielefeld University Library, it contains papers, datasets and theses from institutional repositories and other collections of academic publications. Approximately 60% of the items are open access.
• CORE - CORE aggregates open access research papers from repositories, journals and other web resources.
• openDOAR - openDOAR is a directory of open access repositories, including institutional, disciplinary and governmental repositories holding conference papers, reports, working papers, journal articles, books and more. You can browse by country or do an advanced search to find specific repositories.
• Lenus - The Lenus collections include peer reviewed journal articles, grey literature, dissertations, reports and conference presentations. It also contains the publications of the Irish Health Service Executive (HSE) and the collected research output of over 130 Irish health organisations.

Preprint Repositories:

• MedRiv - An archive for preprints in medical, clinical and related health sciences disciplines
• Wellcome Open Research - An open access publishing platform for scientific, translational and clinical research that has been funded by Wellcome. Includes data, research findings, protocols and case reports. There is an open peer review process, with all peer review comments visible to all users
• Zenodo - An open access repository hosted by CERN. It includes preprints, journal articles, reports, datasets, presentations and other research outputs.
• HRB Open Research - A platform for HRB-funded researchers to rapidly publish their research outputs in an open and accessible way. There is an open peer review process, with all peer review comments visible to all users.
• The King’s Fund - The King’s Fund is a charitable organisation producing reports and research into health and social care in the UK.

You should evaluate grey literature using the same criteria as other literature. See two evaluation tools below to help you critically appraise grey literature. 

CRAAB checklist: (Taken from Murdoch University Library)

Currency - does the date fit with the research purpose? If the material is older, try to find an updated version. It is best to leave the data if a date cannot be found. 
Relevance - is it significant? Does it enrich or have an impact on the research? Have limitations been imposed and are these stated clearly?
Authority - has the report come from a reputable institution or organisation?
Accuracy -  is it supported by documented and authoritative references? Is there a clearly stated methodology?
Bias - is the source objective? Look carefully at commercial or political sources for funding bias. Studies with more 'positive' results - those which show a definite effect for an intervention - are three times more likely to be published than ones which show little or no positive effect.

The AACODS checklist created by Flinders University is also a useful tool for evaluation and critical appraisal of grey literature.

Authority: who is responsible for the content?
Accuracy: is the content clear and consistent?
Coverage: what is the scope?
Objectivity: what are the underlying biases (stated or unstated)?
Date: how current is the content?
Significance: is the resource meaningful, representative, or impactful?