Searching for studies Search methods Systematic reviews are based on studies found by a comprehensive literature search. These standards set out best practice for conducting and reporting searches.
There is growing recognition that grey literature can be useful in systematic reviews.
Searching for grey literature can be difficult, as it is not produced for commercial purposes, lacks bibliographic controls and may not be indexed in major databases. While there are publications that provide useful information about numerous sources for finding grey literature, detailed information about how to systematically search them is often not provided.
Similarly, practical advice is lacking on how to incorporate potentially large yields into a review. This poster will describe a systematic and practical approach to searching and including grey literature in a systematic review based on a review about participatory ergonomics.
Our approach included sources that could be searched systematically, such as databases that include grey with peer-reviewed literature, databases focused on specific grey literature types eg.
Documents were also identified through hand-searching of conference proceedings or were recommended by subject experts, stakeholders, or review team members. Our full search strategy was modified to accommodate those databases with less sophisticated search capabilities.
Test searches in Google, Google Scholar and six Internet repositories produced unmanageably large yields or non-relevant results and were not included in the review. Seventeen electronic databases were searched. Grey and peer-reviewed literature was tracked throughout the review.
This poster describes an approach to searching for grey literature that is both systematic and practical. It focuses on those sources that can accommodate search strategies and allow download of references into bibliographic software programs. Issues of time and resources will also be discussed.Search methods Systematic reviews are based on studies found by a comprehensive literature search.
Cochrane review teams are expected to search a variety of sources in order to minimise the effects of publication bias. Grey literature refers to both published and unpublished research material that is not available commercially.
A review can be biased when it fails to report crucial information that may be hidden in some grey literature. A search of grey literature is one way to address potentially biased reporting. A systematic review conducted in by members of the Cochrane methodologies team found that often the results from grey literature significantly affect the outcome of a review, as they often report more negative or inconclusive data than published journal articles (Hopewell et al., ).
The System for Information on Grey Literature in Europe, is an open access database to bibliographical references of gray literature produced in Europe and allows you to export records and locate the documents in many research disciplines.
The purpose of this paper is to provide a detailed account of one systematic review team's experience in searching for grey literature and including it throughout the review. We provide a brief overview of grey literature before describing our search and review approach.
To review systematically research studies, which have investigated the impact of grey literature in meta-analyses of randomized trials of health care interventions.
Search strategy: We searched the Cochrane Methodology Register (The Cochrane Library Issue 3, ), MEDLINE ( to 20 May ), the Science Citation Index (June .