If you are doing a literature-based project you will need to do a much more thorough and systematic literature search and analysis of the literature. Like a lab-based project you should still be devising a research question to answer by identifying a gap in knowledge.
You should not just produce a descriptive summary of the literature. Instead you will need to compare results reported in the literature, using the existing studies to answer your research question. Evaluate the literature you find for inclusion and quality. You should aim to add to the knowledge by producing your own graphs, tables or data drawn from the literature to create new interpretations of the knowledge.
In some cases literature driven projects are similar to journal review articles that bring together and analyse all the research on a particular topic. However it is still a research project it should include:
The skills of note-making, referencing, structuring and writing explored in the 'Analysing the literature' pages in this guide will all be very relevant to your project. Your analysis of the literature will be woven throughout most chapters of your whole report as opposed to being found in a single literature review/introduction section (as in a lab-based project).
Not all literature driven projects are identical and different techniques and styles will be required depending on the topic you are researching, for example you could be carrying out a systematic review, critical review or meta-analysis using the literature. Therefore it is important that you speak with your supervisor at the beginning of the project to identify the style of literature analysis you will be carrying out.
If you are doing a systematic review take a look at our separate guide:
The International Food Information Service also have a detailed guide to conducting systematic searches for food-related topics:
Key resource for finding publications in the sciences of food and health. Includes over 5,500 journals, plus books, trade publications, conference proceedings, patents and more. Updated weekly. All journals are assessed for quality so you can be confident FSTA does not contain any fake science.
References to journal articles in the biomedical sciences. Covers 1950 to the present day. Includes 'In press' articles.
Gives references to journal articles, books, conference proceedings and patents in all subjects. Also offers extensive tools to analyse results, and measure impact for articles, journals and authors.
Use to search across a number of databases covering a range of subject areas. Provides references to journal articles, books, conference papers, patents, research data and other materials.
See the Key resources page on the food guide for other subject-specific database which might be useful:
Before you start you MUST carefully consider what words you need to include in your search. Think about...
To get started try a search for your basic keywords on Summon, the Library's discovery service. Look at the title, abstract and keywords in any relevant articles - what other terms are used to describe your concepts? Add them into your list of alternatives.
Use the template below to analyse your topic - breaking it down into separate concepts, working out alternatives for each concept, and deciding on any limits. Discuss this with your supervisor.
How are you going to decide which papers should be included in your study? Create a list of inclusion and exclusion criteria. This could include the following:
It might be possible to include some of these criteria in your search. But mostly you will use your inclusion and exclusion criteria to judge each article, firstly by reading the title and abstract, and then by reading the full articles of those which appear to be relevant. This will enable you to filter your results down to the most relevant studies.
Discuss your inclusion and exclusion criteria with your supervisor.
The following techniques work on most databases to build a comprehensive search.
Although databases have developed, and some will automatically search for variant spellings and plurals, mostly they will just search for the exact letters you type in. Use wildcard and truncation symbols to take control of your search and include variations to widen your search and ensure you don't miss something relevant.
A truncation symbol (*) retrieves any number of letters - useful to find different word endings based on the root of a word
medic* will find medic, medics, medicine, medicinal... and any other words beginning with medic
Wildcards can be used to stand for one or no letters within a word. They can be useful for retrieving alternate spelling spellings (i.e. British vs. American English) and simple plurals Wildcard symbols vary between databases - check the help. PubMed does not support wildcards. The following work on Web of Science:
- the wildcard symbol (?) replaces a single letter e.g. wom?n will find woman or women
- the wildcard symbol ($) stands for one or no letters e.g. behavio$r will find behaviour or behavior
Search operators control how your words are combined. Using operators means you can search for all of your terms at once rather than carrying out multiple searches for each alternative.
There are three main operators:
If you have words you want to search for together, as a phrase, you can specify this by enclosing them in double quotation marks e.g. "cardiovascular disease". This makes your search more specific, will reduce the number of results you find and increase the relevance. Note that on Scopus instead of using quotation marks you use these brackets { } e.g. {cardiovascular disease}.
Once you have all your keywords and their alternatives you can build a search statement like this:
(prebiotic* OR probiotic*) AND ("inflammatory bowel disease" OR "ulcerative colitis" OR "crohn's disease")
Note the way the sets of alternative words combined with OR are enclosed in brackets. This ensures correct processing of the search.
On Web of Science and Scopus you could use the Add row/Add Search Field option to enter each set of keywords in separate boxes and it will insert the AND operator and brackets for you. On PubMed you can use the Advanced search to build the statement for you.
It might be possible to use the limit options on databases to apply some of your inclusion/exclusion criteria to your search results. Standard ones available on all databases include:
On PubMed it is also possible to limit in additional ways:
If it is not possible to apply a limit on the database you are using you might need to add an extra concept to your search statement. For example, when searching Scopus if you are only interested in human studies you will need to add 'human*' as an extra search word.
It is important to keep an accurate record of your searches as this will help you plan and revise your search.
Managing your search resultsOnce you have finalised your search statement you should aim to run the search on your chosen databases on one day and download the results to a reference management tool. EndNote is recommended because...
Download it and use the guidance via the link below to learn how to use it.
See the video and guide below for step-by-step instructions on using EndNote to manage the results of your literature searches for your critical review. Although they refer to doing a systematic review, following the same process for managing and analysing the literature for your critical review will ensure you use a structured approach.
A PRISMA diagram, such as the one shown above, is a standard way to record the number of records retained at each step in the literature search and review process. Download a template using the link below. Use the first template on the page if you are only searching databases. If you are finding references by searching Google, Google Scholar or via citations in key papers you will need to use the second template on the page.
Jump to around 1 minute 18 seconds in to this video for an explanation of filling in the PRISMA flow diagram:
If you are unable to access the full-text of articles you need for your project we can usually get them from another library via our inter-library loans service. You can request up to 10 articles from this service. On filling in the request form you will usually receive the article by email within a couple of days.