This section of the Guide explains how
information in the Cochrane Library is organised and highlights some of
the search functionality. If you are new to the Cochrane Library, the
examples given here show how, with a little practice, you can navigate
your way around the Library to find the information you are looking for.
One tip to remember is that you can return to the Cochrane Library opening
screen directly from any other page simply by clicking on the Home
link at the top of the screen.
There are two ways to find information in the Library. From the Cochrane
Library opening screen you can either choose to browse the content or
use one of several search options.
The BROWSE feature is the best way to get an overview
of the range of conditions and topics covered by Cochrane reviews.
Selecting By Topic brings up a list of 52 topics (corresponding
to the 52 Cochrane review groups). The number beside each topic indicates
the number of relevant reviews and protocols (reviews in progress). To
see the titles of these reviews and protocols and to link straight to
the full-text, simply navigate down the hierarchy by expanding the topic
you're interested in.
An alternative to browsing By Topic is to select By
Review Group. Selecting a review group will jump to an alphabetical
listing of that group's protocols and reviews. You can view the full-text
of any review or protocol simply by clicking on the title.
Selecting A-Z brings up an alphabetical listing of the
5000-plus completed reviews and protocols. The selection can be further
refined by choosing to browse just Protocols or Reviews.
The New Reviews and Updated Reviews
options bring up an alphabetical listing of reviews and is a useful way
of quickly seeing what new and updated topics have been covered in this
issue of the Library.
For the Other Resources, the browse feature brings up an alphabetical
listing of the contents of each database. Note, that because of the very
large number of records in the clinical trials database the browse function
is not available for this part of the Library. Selecting Clinical
Trials takes you to the Advanced Search page.
The most basic search can be done from the opening page of the Cochrane
Library. To the right of the screen there is a single search window where
you can enter your search term(s). The default is to search for your selected
term(s) or phrase in the Title, Abstract or Keywords fields.
When using this basic search option, searches are performed across all
the databases. For example, searching arthritis will
retrieve records from the Cochrane Database of Systematic Reviews
(Cochrane Reviews), the Database of Abstracts of Reviews of Effects
(Other Reviews), the Cochrane Central Register of Controlled
Trials (Clinical Trials) plus any other database which contains records
with the word arthritis.
The number of records or 'hits' retrieved in each database by that word
or phrase appears in the Search Results. The default
display is to show the results in Cochrane Reviews. In the example below,
you can see that arthritis (as a word in the Title, Abstract or Keywords)
appears in 99 out of the 5320 records in the Cochrane Database of
Systematic Reviews, in 92 records in Other Reviews, in 4995
records in the Clinical Trials database, etc. Switch between
databases by clicking the relevant link.
In the list of Cochrane reviews that follows, reviews and protocols appear
in order of relevance (matched) in multiples of 25. If you only want to
look at complete reviews then use the Restrict to function
to the right of the screen. View the full-text of a review by clicking
on Record or click the 26-50 link to
view the titles of the next 25 reviews. Reviews can also be sorted by
Record title or Year.
It's worth remembering that the first three resources in the Cochrane
Library are arranged as a hierarchy of evidence. Once you've done a search,
look first to see whether there is a Cochrane review on your topic, if
there isn't, check Other Reviews for any other systematic reviews. If
you still can't find a review relevant to your area, then Clinical Trials
will tell you about any trials that have been conducted.
The Cochrane Library also supports phrase searching. So for example, if
you want to see what there is on low back pain, a search on "low
back pain" retrieves any record which contains these three words
as a phrase (i.e. appearing next to each other). Note, that you need to
insert the phrase within quotation marks to create an exact match.
» Field searching
Restricting searches to the Title, Abstract or Keywords should be sufficient
for most searches, especially since search results for Cochrane reviews
and Other reviews are ranked by relevance. However, to restrict to other
fields or to search all text in the Library, you can select the appropriate
option from the drop-down menu.
Be aware that if you select Search All Text you may find your search retrieves
many hundreds of records, some of which might not seem very relevant when
you browse the titles. The reason these records show up is because somewhere
in the text the authors have mentioned the word arthritis, even though
arthritis may not be the main subject of the record.
If your search returns too many irrelevant records and you want to be
more precise, then there are several other ways of refining your search.
For anything but the most basic of searches, the Cochrane
Advanced Search page is the place to start.
» Combining terms using AND
Because the Cochrane Library contains a lot of information, you may find
some search terms retrieve an overwhelming number of records (even after
restricting your search to the title or abstract). If you're looking for
information about a particular treatment for a specific condition, then
it's often quicker and easier to combine these in the same search using
the AND operator.
For example, corticosteroids are used in the management of acute severe
asthma. To search for records in the Cochrane Library that contain BOTH
the word asthma AND corticosteroids you would enter the search asthma
and corticosteroids.
» Combining terms using OR
Sometimes it's helpful to use multiple words to search for a single topic.
This would be the case if the condition or intervention is referred to
differently in different parts of the world, or if there are different
spellings (e.g. British English vs American English). It's also helpful
to combine synonyms (e.g. bed-wetting is the same as enuresis).
Searching on viagra is an example of when it would be sensible to use
OR, since viagra (its proprietary name) is also referred to as sildenafil
(its generic drug name). In this example, a search on viagra or
sildenafil retrieves any record which contains EITHER of these
two terms.
» Truncation
Sometimes the topic you're interested in may have several variations,
for example pregnant, pregnancy or pregnancies. You could search each
of the words individually, but it's quicker to use the truncation facility.
Inserting an asterisk (*) after the main stem of the word retrieves all
variant endings, so pregnan* will retrieve pregnant, pregnancy or pregnancies.
You can also use the truncation symbol at the beginning of a word, so
*eclampsia will retrieve pre-eclampsia and preeclampsia as well as eclampsia.
For greater flexibility choose Advanced Search. The Advanced Search
screen allows you to build searches by combining several different concepts
using Boolean operators (AND, OR or NOT) and lets you limit your search
according to particular databases, types of record or year(s).
The following example shows how you might use the Advanced Search if you
were interested in finding out about the benefits of using fluoride toothpaste
to prevent dental caries in children.
In this example we have chosen to restrict to Title, Abstract or Keywords.
You will need to change the default selections from Search All Text, Record
Title and Author.
Searches can be further refined by limiting to one or more of the databases
in the Cochrane Library. The default search selection is set to All of
The Cochrane Library. You can also choose to retrieve records according
to their status, for example, if they are new or updated. And finally,
there is the option of limiting your search to a range of publication
years. We recommend keeping the default selections unchanged.
Note that a useful feature of the Advanced Search page
are the Search Tips to the right of the screen. You can
use these tips to check specific search query options.
There are several other search options that can be accessed from the Advanced
Search page.
» MeSH searching
MeSH searching allows users to search for concepts using the US National
Library of Medicine's controlled thesaurus of medical subject headings.
For casual users of the Library, you can safely ignore this search option.
A detailed description of MeSH searching can be found in the Search
Tips to the right of the page.
» Search history
Search History allows you to view searches run during your current search
session. It's a useful feature that allows you to build searches by combining
several search concepts. The example below shows how searches are built
using search ID numbers.
» Saved searches
Saved searches provides a method for storing and maintaining individual
searches and search strategies. You can save individual searches by clicking
the Save Search Strategy button on the Search History
page.
Note: to take advantage of this feature, users first have to create a
profile and then log in. To create a profile, click on Log In
in the top right-hand corner of the Library and select Register
Now. Registration is free and requires you to provide an email
address and password.
In this section of the Guide we have highlighted the main features of
searching the Cochrane Library. For a more detailed description of each
search function, either browse the Search Tips that appear
to the right of the screen when you select Advanced Search, MeSH Search
etc. or choose Help from the Library homepage.
Resources available from the Library Help page include the User
Guide (Version 2.2) developed by the Library's publishers. This
29-page booklet is available as a PDF file and gives an overview of the
Cochrane Library on Wiley InterScience. It provides some useful supplementary
material on aspects of the Library that haven't yet been covered in detail
in the ACC User Guide, such as how to export citations and display the
meta-analysis diagrams. The User Guide is available in several languages.
There is also a shorter Quick Reference Guide.
The publishers of the Cochrane Library and the Cochrane Collaboration
are continually looking to make the Library more user-friendly. You can
pass on your comments on any aspect of using the Cochrane Library by clicking
the Feedback button
at the top of the page.
