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Police Degree Programmes: Search Tips

What is a Literature Search?

Pile of books

A literature search is a systematic and comprehensive search for information.

The information you search for will inform, underpin and /or shape your research. 

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

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

How to undertake a literature search

When searching the Internet or library resources, get the best search results by using some of these search tips:

Broaden your search

  • To provide more results (expand) use OR between the keywords. This is useful when something can be described in different ways e.g. USA OR America
  • Some databases allow you to broaden your search by using the stem of a word and an asterisk* to find variant endings e.g. Crim* .  
    • This will find crime, crimes, criminal, criminals, criminology, criminologies, criminologist, etc.
  • Use a question mark ? to find different spellings e.g. organi?ation (finds organization and organisation)

Narrow your search

  • To add 2 topics together use AND between the keywords e.g. crime AND security
  • Using brackets allows you to perform quite sophisticated searches. this is especially relevant to internet searching e.g. ("circles of support and accountabilty" AND "probation service") AND crime*

Search for a phrase

  • To ensure that words always appear together as a phrase, enclose with “quotation marks” e.g. “probation service"

Academic sources

  • In order to find information on a specified subject which originates from academic sources such as University websites, include +ac (British) or +edu (USA) to your search e.g. "crime prevention" +ac 

Exclude words/topics

  • To exclude topics which are irrelevant or not wanted use NOT between the words e.g. "Crime prevention" NOT CCTV
  • A minus sign (-) can also be used to exclude a term when searching the Internet e.g. to find information on whistleblower and not sport, enter whistleblower -sport*

Exact match

  • Many search engines on the Internet find synonyms automatically i.e. they will find center if you have searched for centre. 
  • Use a plus symbol (+) or "quotation marks" to ensure a specific spelling of a word is found e.g. +Excel or "Excel"


  • To find similar websites to one that you have already found use Related: e.g. Related:  will find other websites which are similar to the National Probation Service website
  • Use site: to search within certain types of websites with either a specified subject (e.g. design)  or domain (e.g. academic websites) eg. to search for statististics in crime or academic websites use Statistics site: crime or Statistics site: ac

Getting answers

  • To find a definition of something use Define: e.g. to find a definition of Bayesian statistical modelling use Define: "criminal justice system"
  • To get an answer to a question use an asterisk * e.g. to find out what John Howard developed enter john howard developed*

Literature search strategy

In order to develop an effective search strategy, you will need to have formulated a clearly defined question. This will allow you to identify appropriate keywords which you can use to search with.

You will also need to consider the resources that you are going to use in order to find information i.e. appropriate journal databases and/or other resources.

It is also important to consider what you want and what you don't want (Inclusion/Exclusion criteria) e.g. language, length of trial/study, publication date etc.

Before you start your literature search use the worksheet below to plan your search strategy. A 'completed' version is included to show how the worksheet is used.

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

A simplified version (Keywords: Improving your search) can also be used to help you come up with search terms.