Psychology & Counselling

Systematic and Scoping Literature Searches

This page is aimed at postgraduate psychology students who will be undertaking a systematic literature search for their thesis and require guidance on performing effective and comprehensive searches. The guide may be useful for students on other programmes, but they should seek guidance from their tutor and/or their academic services librarian in the first instance.

Scoping Search

Before embarking on a systematic search of the literature, it is important to perform a scoping search to provide an overview of the literature in your area of research.

Booth et al (2022, p. 23) define a scoping search as a:

“Preliminary search designed to (i) identify existing reviews in your topic area and (ii) estimate the existing quantity and quality of relevant primary studies. Typically, scoping searches do not aim to be fully comprehensive.”

A scoping search does not need to be exhaustive and comprehensive. It should, however, give an indication of the amount of research and should help to confirm gaps in the literature.  

When conducting a scoping search, it is important to focus on using terms that will retrieve results that are highly likely to be relevant if present, rather than broader search terms that will bring back a lot of irrelevant articles (Booth et al., 2022). Index terms can be particularly useful in ensuring a narrow, focused search of the literature (see: Subject Terms and Controlled Vocabularies).

In terms of where to search, scoping the literature in one or two databases is valuable and sufficient in indicating how much literature already exists (Atkinson & Cipriani, 2018).

Systematic Searching

A scoping search should inform a systematic search of the literature, particularly in terms of helping to identify keywords and develop a search string that will ensure a comprehensive search of the literature.

When conducting a systematic search of the literature, there are a few things to consider:

1. What keywords and index terms do you need to use to ensure a thorough search of the literature?
2. Which databases are relevant for your research? Think broadly about your subject, don’t just restrict yourself to APA PsycInfo.
3. What is your inclusion/exclusion criteria?
4. Explore terms used in articles found in your scoping search to inform your search strategy.
5. Create your search string with a mixture of subject terms and keywords (where appropriate) and using search operators (see below). Search each of the identified databases using your search terms (your search string may need to be adapted for each database, depending on the features available).
6. Collect identified, relevant papers in reference management software, such as Zotero (we provide support for both Zotero and Mendeley).

Subject Terms and Controlled Vocabularies

A number of databases use subject terms as a way of categorising items within a database. These terms are applied using a specific thesaurus or controlled vocabulary to ensure all items within the database are categorised in exactly the same way.

Databases that include a thesaurus or controlled vocabulary include:

APA PsycArticles/PsycInfo - APA Thesaurus of Psychological Index Terms

Ebsco Academic Search Complete – Subject Terms

MEDLINE (PubMed) - Medical Subject Headings (MeSH)

The Cochrane Handbook (Searching for and Selecting Studies, 2022) suggests searches should comprise a combination of subject terms selected from the controlled vocabulary or thesaurus (‘exploded' where appropriate), and a wide range of free-text terms in order to retrieve as many relevant records as possible.

• If you use keywords only, you could miss articles that do not use your precise terms.

• If you use controlled vocabulary only, you could miss articles that have not been indexed yet or have older indexing.