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Psychology: Search Skills

Boolean Searching

Use Boolean Operators to build your search and link your search terms


OR = more

You can use OR to expand a search and combine terms.
This means that any of the terms you specify can appear in your results.

Venn diagram image of a search using boolean operator OR


AND = less

AND reduces a search by requiring all terms to appear in our results.
To add topics together use AND between the keywords

Image of a venn diagram search using boolean operator AND

Exclude words/topics

  • To exclude topics which are irrelevant or not wanted use NOT between the words e.g. Computer games NOT video
  • A minus sign (-) can also be used to exclude a term when searching the Internet e.g. to find information on Apple computers and not apples (fruit), enter Apple -fruit

Search for a phrase

To ensure that words always appear together as a phrase, enclose with “quotation marks” e.g. “human computer interaction"

Some databases allow you to broaden your search by using the beginning of a word and an asterisk* to find different endings e.g. Comput* (this will find computers, computer, computing, computerisation, computation etc). This is called a "Wildcard" search. Check the help function of the database you are using to see if it is supported.

Using brackets allows you to perform quite sophisticated searches. This is especially relevant to internet searching. Using brackets allows you to combine a selection of Boolean Operators together.


A quick introduction to keywords

Critical Thinking

The further you progress in your studies the more you will need to evaluate and critically examine your research.

In a healthy debate, there are different people with different ideas. When carrying out their own research, students are expected to seek out a range of perspectives, to read widely, that is. This is a bit like 'listening' to different participants in a debate.

It is important to 'listen' (or read) with a certain amount of doubt in mind. Do not simply accept what each person writes, instead ask questions in response such as where have the authors got their information, how have they backed it up? where is their proof or evidence? Answering these questions is an important early stage of critical analysis.

Being critical means identifying the advantages of ideas just as much as identifying the limitations.

A quick introduction to literature searching

Thanks to my colleague Linda Pearson for creating this video and the one on using keywords.

Literature search planning worksheet

Before you start your literature search...

Use the worksheet below to plan your strategy

Planning your literature search in this way should help you work in a more systematic fashion and will provide you with a record of what you have done for when you write up your research methods

Literature Searches

A literature search is a systematic and organised investigation across a range of sources for material relevant to your topic.

A literature search will enable you to find out what has already been written in your subject area and identify the main trends. 

The information may be found in books, journal articles, reports, case studies, policy documents, conference proceedings etc.

10 Tips for literature searching

Literature Reviews

Research Methods

Systematic reviews

Systematic Reviews:

SRs are used in evidence based medicine to ensure that practitioners have the best available evidence in order to decide how to treat patients. SRs are now applied to other disciplines.

Within the health discipline there may be lots of research being carried out, but not necessarily a summary of what has been done. There is a need to bring the research together to see if there is consensus of evidence from trials. Therefore a systematic approach is used to ensure that all research is found and evaluated.

•Clearly defined research question
•Aims for comprehensive, exhaustive searching
•Transparent methods – SR are explicit about how the search has been carried out i.e. transparent about method i.e. same filters, terms etc so that search can be replicated. e.g. only looks at research that looks at experimental trials in England etc.
•Pre-specified eligibility criteria to determine what’s included
•May include a meta-analysis – statistical analysis of the combined results of quantitative studies i.e. pool all the data from different studies to get an overall answer.
•Seeks to systematically search for, appraise and synthesise research evidence, often adhering to guidelines on how to conduct a review (e.g. PRISMA)

The PRISMA Statement was developed by an international group with the aim of transparent reporting of systematic reviews and meta-analyses. The PRISMA Statement consists of a checklist and a flow diagram. The latter is useful for recording the flow of information through the different phases of a systematic review.
PRISMA Flow Diagram Generators

This is an updated version of the original PRISMA flow generator. Includes a downloadable PDF version.

Contains both PDF & Word versions. From PRISMA.

Critical Appraisal

Critical Appraisal is the process of assessing and interpreting evidence by systematically considering its validity, results and relevance. The following resources provide a useful introduction to this process:

Understanding Research Methodologies

Critical appraisal of the evidence

Critical appraisal is the process of evaluating and interpreting evidence by systematically considering its validity, results and relevance.  The following resources should provide a useful introduction to this process:

Articles about critiquing research: