Evidence Synthesis in the Social Sciences
Bibliographic Databases | Platforms | Syntax
Database
A bibliographic database is a searchable collection of references to books, articles, and other published works, often including abstracts and citations, used for research and academic purposes.
Platform
A platform or database supplier provides access to bibliographic databases through different search interfaces.
For example, the US Department of Education sponsors the ERIC database, which can be searched via the free, publicly available government website. ERIC is also available through commercial search platforms, such as ProQuest and EBSCO. The ASU Library provides access to ERIC through ProQuest, which offers additional functionality not available on the free platform.
Syntax
The platform on which you conduct your search is essential because it dictates the syntax that you will use to conduct your search. Syntax refers to the punctuation, symbols, operators, and search fields in a search query that tells a database how to run a search. For this reason, your search might not be compatible with other platforms, making it essential for readers to know which platform was used to ensure reproducibility.
Tip: Even if you access a database through a library subscription, it's a good idea to set up a free personal account on the database platform beforehand. This can boost your export limits and allow you to save your searches.
Identifying Sources
The goal of systematic review searching is to identify as many relevant studies as possible to the research question. Searches should be comprehensive and NOT limited to, for example, top-tier journals or peer-reviewed literature. Therefore, choosing several databases to achieve comprehensive research coverage and minimize selection bias is essential.
Choose databases that cover the full scope of your topic, including any interdisciplinary connections relevant to your research question. Consider a wide geographic range, ensuring you include databases that focus on regions outside the US and Europe if they align with your inclusion criteria.
Collaborate with a librarian who has expertise in the relevant disciplines to identify the most suitable databases for your search.
- Campbell guidance for choosing sources (Section 3)
- Select both broad, multidisciplinary, and discipline-specific databases.
- Grey literature
- Contact experts in the field
Remember that obtaining the full text of articles is a separate issue and will depend on our institutional journal subscriptions or the availability of free, open-access versions. Once you reach that stage, ASU's interlibrary loan service (ILL) can be valuable for securing full-text access.
References: Kugley, S., Wade, A., Thomas, J., Mahood, Q., Jørgensen, A.-M. K., Hammerstrøm, K., & Sathe, N. (2017). "Searching for studies: A guide to information retrieval for Campbell systematic reviews." Campbell Systematic Reviews. Volume 13. Number 1. 1-73 Pages. https://doi.org/10.4073/cmg.2016.1.
What is Grey Literature?
Grey literature refers to a wide range of information produced outside traditional publishing and distribution channels, and is often underrepresented in indexing databases.
Grey literature is typically defined by what it is not: it is any document not issued by an entity with publishing as its primary purpose.
Any of the following types of documents can be grey literature:
- Government documents
- Industry/NGO reports
- Think-tank papers
- Working papers
- Author manuscripts
- Dissertations/theses
- Conference abstracts/proceedings
It is important to note that grey literature is not synonymous with either of the following, which are sometimes confused with grey literature:
- Non-peer-reviewed literature: Much grey literature is reviewed before publishing. Some literature issued by academic/commercial publishers is not.
- Material not indexed in academic databases: Some grey literature is indexed in specific databases. Common examples include conference proceedings/abstracts and dissertations/theses.
However, much grey literature is not indexed in traditional databases.
- PsycEXTRA browses grey literature, including conference presentations, reports, fact sheets, and newsletters, providing access to unique and innovative content in psychology and the behavioral sciences.
- PsyArXiv is a free archive of preprints, working manuscripts, and postprints in the field of psychology. PsyArXiv does not perform peer review. Instead, it employs a basic moderation process to remove spam and ensure that submissions are relevant to the field of psychology.
- Dissertations and Theses Global
This table includes a preprint repository and search syntax to help you locate open-access or grey-literature preprints. Reference: Premji, Z., & Riegelman, A. (2024, October 25). Preprint repository search syntax table.
The AACODS checklist is designed to enable evaluation and critical appraisal of grey literature.
What about Google Scholar?
Google Scholar may be a good supplemental choice, particularly for grey literature. However, Gusenbauer and Haddaway (2020) go as far as to say, "Google Scholar's extraordinary coverage acting as a multidisciplinary compendium of scientific world knowledge should not blind users to the fact that users' ability to access this compendium is severely limited, especially in terms of a systematic search. Google Scholar does not publicly disclose their search engine's algorithms, nor do they accurately explain what is included in their search results" (211). Google Scholar's search interface lacks most of the features systematic reviewers find the most useful, including commanded line searches, saved history, and consistency in results.
References:
Gusenbauer, M., & Haddaway, N. R. (2020). Which academic search systems are suitable for systematic reviews or meta‐analyses? Evaluating retrieval qualities of Google Scholar, PubMed, and 26 other resources. Research synthesis methods, 11(2), 181-217. Source: Wiley Online Library.
Haddaway, N. R., Collins, A. M., Coughlin, D., & Kirk, S. (2015). The role of Google Scholar in evidence reviews and its applicability to grey literature searching. PloS one, 10(9), e0138237. Source: PLOS One