A database is a searchable collection of information. In library research, a database is where you find journal articles.
Each database contains thousands of articles which you can search for simultaneously and quickly to find articles with higher relevancy than searching in individual journals.
The most common databases used in the NHS are:
- Pubmed is freely searchable and contains 32 million citations for biomedical literature from MEDLINE, life science journals, and online books.
- Cochrane Library
- The Cochrane library is also freely searchable and contains citations from Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Clinical Answers and more.
- Contains over 29 million records from more than 8, 500 journals from at least 90 countries. It is an Elsevier owned database which requires an institutional login or subscription to access.
- NICE Evidence search
- Freely searchable and sources include the British National Formulary, Clinical Knowledge Summaries, SIGN, the Cochrane Library and Royal Colleges, Social Care Online and GOV.UK.
Searching for a paper:
This section will show you how to search the Pubmed database for articles you are interested in.
MeSH (Medical Subject Headings) is the National Library of Medicine’s controlled vocabulary thesaurus, used for indexing articles for the MEDLINE®/PubMED® database. Each article citation is associated with a set of MeSH terms that describe the content of the citation.
Pubmed itself has a very useful set of guides on how to use it and get the information you want, and I can’t really improve on its clarity. It is a very intuitive system and just typing in the subject you are interested in and hitting ‘Enter’ should be enough to give you a pretty close match to what you need.
“I’m doing a literature review, how do I find the right papers and make sure I haven’t missed anything?”
A literature review is a search and evaluation of the available literature in your given subject or chosen topic area. The steps to write one are as follows:
- Search for relevant literature
- Evaluate sources
- Identify themes, debates and gaps
- Outline the structure
- Write your literature review
So how do you do step 1?
Choose your key themes and keywords, for example if you are looking to do a review on the use of fentanyl in obstetric rapid sequence inductions, your key words are likely to be “fentanyl”, “obstetric” and “rapid sequence induction”.
You can then note down the most common similar terms that might have been used in addition to those, eg. “opioids”, “caesarean section”, “general anaesthetic”.
If you typed in “fentanyl”, “obstetric” or “rapid sequence induction” into Pubmed, you’ll likely find information about one or more of these, for example fentanyl patches in labour analgesia; or rapid sequence induction in obstetric patients, but not all three. Pubmed recognises Boolean operators, so if you type in the following in between, you’ll get what you’re looking for.
- AND to find sources that contain more than one keyword (e.g. fentanyl AND obstetric AND rapid sequence induction)
- OR to find sources that contain one of a range of synonyms (e.g. obstetric Z OR Caesarean section)
- NOT to exclude results containing certain terms (e.g. fentanyl NOT remifentanil)
It is worth searching for each term and then combining them using the search numbers eg. 1 AND 2 AND 3 below.
Once you’ve done your search on Pubmed, you’ll probably have too many results. You can filter that down further using the ready available filters on the side bar (as shown below). There are more filters than listed in the photo.
If you are writing up your literature review, please remember to note down exactly which filters you have used to get the papers you did so that it is reproducible.
More advanced search options are available on Pubmed, shown in the videos below – if you need something like that done, do ask your local medical librarian who will have the expertise to help you!
Once you’ve done your searches, you can save your search history by clicking the ‘Download” button, or redo the whole search using “Delete”.
- How to improve your PubMed/MEDLINE searches: 1. background and basic searching: https://pubmed.ncbi.nlm.nih.gov/24197398/
- How to improve your PubMed/MEDLINE searches: 2. display settings, complex search queries and topic searching: https://pubmed.ncbi.nlm.nih.gov/24352897/
- How to improve your PubMed/MEDLINE searches: 3. advanced searching, MeSH and My NCBI: https://pubmed.ncbi.nlm.nih.gov/24614997/
Writing a literature review might include reading a number of articles and referencing them later. You can of course do this yourself manually by saving PDFs of each article and manually citing them in your manuscript and writing a reference list later. But that is a lot of hard work!
Reference management software is available for you to use to help streamline this process.
The most common ones used include:
Endnote – The basic software is free but the advanced package requires a paid subscription. Many career researchers and writers opt to use the paid version (usually from their institution) which is a lot more powerful, but if you are just starting out and using a few references as a once off then the basic software is fine for your needs. It operates from a web browser (free) or a downloadable application for your windows/Mac/iPad (paid). Both versions sync to Microsoft Word 2016 and onward (see how to use it here) so you can write your manuscript and directly put in references which will be numbered accordingly and formatted the way you want it.
Papers – This is a paid package software for Apple users.
RefWorks – This is also a paid package software for Mac and Windows – many institutions have subscriptions to this.
Zotero – This is a free, open source software for Mac and Windows users and has offline backup
Mendeley – Also free, useful for collaboration and works for Mac, Windows, and Linux users