1. The Cochrane Library
A Training Guide
Ron Hudson
Outreach Training Librarian
Croydon Health Library and Resources Service
NHS Croydon
12-18 Lennard Road
Croydon CR9 2RS
Tel: 020 8274 6316
Mob: 07733 300 104
Email: ron.hudson@croydonpct.nhs.uk
July 2010
With thanks to Mary Last, Clinical Support Librarian, Bloomsbury Healthcare Library

2. Contents
1. Overview - sources of research-based evidence
Sources of research-based evidence ............................................................. 3
The hierarchy of evidence ............................................................................... 4
2. Introduction to the Cochrane Library
What is the Cochrane Library? ........................................................................ 5
When to use the Cochrane Library.................................................................. 5
Background and history of the Cochrane Library ............................................ 6
The databases ................................................................................................ 7
Definitions ……………………………………………………………………………9
3. Getting started
Accessing the Cochrane Library.................................................................... 10
Site registration and password ..................................................................... 10
Explaining the home page ............................................................................ 12
4. Browsing the Cochrane Library
Browsing the main databases ...................................................................... 13
Cochrane Database of Systematic Reviews Symbols ..……………………….14
Browsing the Cochrane Database of Systematic Reviews ............................ 15
Browsing by Topic.................................................................................... 15
Browsing by Review Group ..................................................................... 15
5. Searching the Cochrane Library
Search tips and tricks ................................................................................... 17
Simple search ............................................................................................... 19
Advanced search .......................................................................................... 20
Search history .............................................................................................. 22
Searching MeSH .......................................................................................... 24
6. Viewing, printing and saving search results
Viewing search results .................................................................................. 27
Different sections of a Cochrane Systematic Review ……………………29
Following up on primary references………………………………………….30
Interpreting graphs ................................................................................... 30
Saving and printing search results ................................................................ 31
Saving a search............................................................................................. 32
Saving a search strategy ............................................................................... 33
Setting alerts ................................................................................................ 35
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3. Overview - sources of research-based evidence
Evidence-based practice has been described as:
… the conscientious, explicit, and judicious use of current best evidence in making
decisions about the care of individual patients. The practice of evidence based
medicine means integrating individual clinical expertise with the best available
external clinical evidence from systematic research.
Sackett DL et al. BMJ, 1996, Vol 312, pp 71-72
The range of the ‘external clinical evidence’ available to health care professionals is
often described as a hierarchy and this is shown on the following page, from individual
opinion at the bottom of the pyramid, through research methodologies of varying rigour.
You can access most of this enormous quantity of research-based evidence through the
primary journal literature by searching databases search as Medline.
There are, however, specialist resources that you can go to which evaluate and
summarise available research evidence when you want to know about the effectiveness
of a particular health care intervention. These can be divided into:
• Reviews
eg Cochrane Database of Systematic Reviews
Reviews are examples of secondary research. Standard reviews compare the results
of two or more primary studies. The systematic review, however, aims to give a full
picture of a topic by identifying all available evidence, appraising it and then
presenting a cumulative summary. This usually includes a meta-analysis, the
combination of results from primary studies into a single statistical result. More
information about systematic reviews can be found on page 9.
• Digests
eg Clinical Evidence
Digests identify the major evidence on particular topics and provide key messages.
• Guidelines
eg NeLH Guidelines Finder
Guidelines provide recommendations for effective practice based on current
evidence.
If you find a systematic review or summary of current evidence which answers your
question you will be saved the work of searching databases for journal literature as well
as much of the reading and critical appraisal involved.
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4. The Hierarchy of Evidence
BEST
A systematic review of at least two randomized controlled trials
A randomized, controlled trial
A cohort study
A case-control study
An uncontrolled study with dramatic results
An expert committee report or similar
Anecdotal evidence
WORST
Harrison S. (ed) Evidence-based medicine: its relevance and application to primary care
commissioning. London: Royal Society of Medicine Press Ltd, 1998.
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5. Introduction to the Cochrane Library
What is the Cochrane Library?
The Cochrane Library is described as the best single source of reliable information on
the effects of interventions in health care. It is designed to provide information and
evidence to support decisions taken in health care and to inform those receiving care.
The Cochrane Library is a collection of databases containing systematic reviews, health
technology assessments, economic evaluations and controlled trials. More information
about each database can be found on page 7. Some databases provide full-text articles,
some just bibliographic details with abstracts.
When to use the Cochrane Library
The whole of the Cochrane Library is concerned with the effectiveness of interventions
for a given health care problem or in a particular health care situation.
The Cochrane Library is useful for answering the following types of queries:
• What is the effectiveness of treatment X in condition Y?
What is the effectiveness of aspirin in vascular dementia?
• Is treatment A better than treatment B?
Is there any evidence that clozapine is more effective in the treatment of
schizophrenia than standard antipsychotics?
• What is an effective intervention to achieve outcome Z?
What are the most effective strategies for stopping smoking?
The Cochrane Library is not useful for these types of questions:
• General health care information
Are there any new drugs for manic depression?
• Statistical information
What is the teenage pregnancy rate?
• Cause, prognosis, epidemiology or risk factors for an illness
What are the health effects of unemployment?
• Guidelines
• Current research (apart from systematic reviews and randomised controlled
trials)
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6. Background and history of the Cochrane Library
Since 1996, systematic reviews prepared and maintained by the Cochrane Collaboration
have been published in The Cochrane Library, along with bibliographic and quality-
assessed material on the effects of health care interventions submitted by others.
Cochrane reviews are a highly regarded source of evidence about the effects of health
care interventions and widely thought of as being of better quality, on average, than their
counterparts in print journals.
The first issue of the Cochrane Library in 1996 therefore incorporated:
• Regularly-updated systematic reviews and protocols for reviews in preparation
• Quality appraisals of reviews published elsewhere
• A register of controlled trials
These collections were viewed as part of a hierarchy of evidence, ranging from regularly
updated reviews, to high-quality reviews published elsewhere, to reports of individual
controlled trials.
There are now six main databases plus one other giving information about the Cochrane
Collaboration and its Review Groups. Further information on each of the main
databases can be found below.
Further information
The Cochrane Collaboration's web site - www.cochrane.org/ - is a useful source of
information. The Newcomer's Guide on it provides background information on the
Cochrane Collaboration and its systematic reviews.
An article about the genesis and history of the Cochrane Library between 1988 and 2003
can be found at www.update-software.com/history/clibhist.htm.
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7. The Databases
Cochrane Database of Systematic Reviews (CDSR; Cochrane Reviews)
A systematic review identifies an intervention for a specific disease or other problem in
health care, and determines whether or not this intervention works. To do this authors
locate, appraise and synthesise evidence from as many relevant scientific studies as
possible. They summarise conclusions about effectiveness, and provide a unique
collation of the known evidence on a given topic, so that others can easily review the
primary studies for any intervention.
As of Issue 4, 2008, this database also includes systematic reviews of diagnostic test
accuracy. Cochrane diagnostic test accuracy reviews are not based on randomized
controlled trials, but mainly on cross sectional studies.
From Issue 2, 2007, this database also includes the methodology reviews that were
previously part of Cochrane Database of Methodology Reviews (CDMR; Methods
Reviews)
Cochrane Methodology Reviews are full-text systematic reviews of methodological
studies. Highly structured and systematic, evidence from methodological research is
included or excluded on the basis of explicit quality criteria, thus minimising bias. Each
review covers a specific and well-defined area of methodology. Data from studies are
often combined statistically to increase the power of the findings of numerous studies,
which on their own may be too small to produce reliable results. In such cases, the
review may also include graphs presenting the data from each individual study.
Protocols provide information about reviews which are currently being written. They
summarise the background and the rationale of the review.
Database of Abstracts of Reviews of Effects (DARE; Other Reviews)
DARE includes structured abstracts of systematic reviews from around the world which
have been evaluated by the reviewers at the NHS Centre for Reviews and Dissemination
(NHS CRD) at the University of York. Only reviews that meet minimum quality criteria
are included in DARE. These reviews cover topics that have yet to be addressed by a
Cochrane review.
Cochrane Central Register of Controlled Trials (CENTRAL; Clinical Trials)
CENTRAL includes details of published articles taken from bibliographic databases
(notably Medline and Embase), and other published and unpublished sources.
CENTRAL records include the title of the article, information on where it was published
(bibliographic details) and, in many cases, a summary of the article. They do not contain
the full text of the article.
Trials are identified from multiple sources, including searches of bibliographic databases,
hand searches of many hundreds of journals and conference proceedings, and searches
of other trial registers.
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8. Cochrane Methodology Register (CMR; Methods Studies)
This is a bibliography of publications which report on methods used in the conduct of
controlled trials. It includes journal articles, books, and conference proceedings. These
articles are taken from the Medline database and from hand searches. The database
contains studies of methods used in reviews and in more general methodological studies
which could be relevant to anyone preparing a systematic review. CMR does not contain
the full text of articles.
Health Technology Assessment Database (HTA; Technology Assessments)
This database contains information on healthcare technology assessments (defined as
prevention and rehabilitation, vaccines, pharmaceuticals and devices, medical and
surgical procedures and the systems within which health is protected and maintained).
The database contains details of ongoing projects and completed publications from
health technology assessment organisations. HTA records follow a standard structure.
Some records contain the title of the project, with the name of the centre responsible and
an indication of where further details can be obtained. Other records contain publication
details, with structured abstracts where available. Records do not, in either case, contain
the full text of the report.
NHS Economic Evaluation Database (NHS EED; Economic Evaluations)
This database contains structured abstracts of articles describing economic evaluations
of health care interventions. The articles are identified by searching through key medical
journals, bibliographic databases and less widely available literature. A paper will be
included if it provides a comparison of treatments and examines both the costs and
outcomes of the alternatives. The database also includes bibliographic details of articles
examining relevant topics, (for example the burden of illness, economic methodology
papers, and reviews of economic evaluations), and short abstracts of studies originally
included in the Department of Health Register of Cost-Effective Studies. Records do not
contain the full text of the original article.
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9. Definitions
Systematic Review:
Systematic reviews differ from other types of review in that they adhere to a strict design
in order to make them more comprehensive, thus minimising the chance of bias, and
ensuring their reliability. Rather than reflecting the views of the authors, or being based
on a partial selection of the literature, (as is the case with many articles and reviews that
are not explicitly systematic), they contain all known references to trials on a particular
intervention and a comprehensive summary of the available evidence. The reviews are
therefore also valuable sources of information for those receiving care, as well as for
decision makers and researchers.
Economic Evaluation:
Full economic evaluations, as defined by the NHS CRD, can be one of the following:
• a cost-benefit analysis (CBA), which measures both costs and benefits in monetary
values and calculates net monetary gains or losses (presented as a cost-benefit
ratio);
• a cost-effectiveness analysis (CEA), which compares interventions with a common
outcome (such as blood pressure level) to discover which produces the maximum
outcome for the same input of resources in a given population;
• a cost-utility analysis (CUA), which measures the benefits of alternative treatments or
types of care by using clearly defined utility measures (such as quality-adjusted life
years)
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10. Getting started
Accessing the Cochrane Library
You can either go directly to the Cochrane Library at www.thecochranelibrary.com or
from the following link:
• National Library for Health (under Evidence Based Reviews) – www.library.nhs.uk
The databases are updated monthly. Also on the National Library for Health site under
Evidence Based Reviews you will find links to DARE and NHS EED which represent the
most up to date versions of these databases. They can be searched individually.
Site registration and password
You do not need a password to access the Cochrane Library or to conduct one-off
searches, view full records or to print or to save them, but if you are likely to be a regular
visitor to Cochrane and would like to be able to save searches and search strategies and
to set up email alerts, you should register yourself on the Wiley InterScience site.
NB You cannot use your Athens username and password to log on to the site.
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2
1. Click ACCESS in the right centre of the screen
2. Click Register for Wiley Interscience
• Fill in the registration form
Your email address and the password you choose will be used as your username
and password for the future. Try to register using your work email address and to
avoid an email address ending in .com. You must also check the box to indicate that
you have read the Terms of Usage. The information you enter will not be used by a
third party.
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11. • Click Submit Registration
You will receive an email confirming receipt of your completed registration form. You
must validate your account by clicking on the link in the message within 24 hours
otherwise you may have to register all over again.
To get back to the Cochrane Library:
3. Type Cochrane in the search box
4. Check the radio button Publication Titles
5. Click Go
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3
5
• Then select the current issue of the Cochrane Library from the list of results
You will now be back at the Cochrane Library home page.
Logging on subsequently
• The next time you access the Cochrane Library and click Log In you are taken to
the main Wiley InterScience home page to enter your username and password. It
is not recommended to check the box Remember Me if you share your computer
with others.
Once you have logged on you will still be on the Wiley page so will need to get back to
the Cochrane Library in the way described above.
Timing out
You will find that after periods of inactivity during a search session you will be timed out
and asked to re-enter your username and password. You will be taken back to where
you were in your search and not lose anything.
6. Always remember to Log Out when you have finished a search session.
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12. Explaining the home page Find out more about
the Cochrane
Collaboration
Return to
the home
page
Click here to log
in if you have
registered for a
Enter your username
search term
Links enabling you
to browse the
resources on the
Cochrane Library
There are different ways of accessing the Cochrane Database of Systematic Reviews.
You can view them:
By Topic – Select a topic of interest and narrow it down
New Reviews – Protocols and Reviews added to the database in the latest
update
Updated Reviews – Only those Reviews which have been recently updated
A-Z – List of Reviews by title (warning, there are over 5,000 titles in
alphabetical order)
By Review Group – Reviews and Protocols by one of the 51 specific Review
Groups
e.g. Cochrane Drugs and Alcohol Group
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13. Browsing the Cochrane Library
Four of the six main databases can be browsed, alphabetically by title, by clicking on
their name. Where necessary use the A-Z links and scroll bar to navigate the lists of
titles presented.
The exception is CENTRAL. Because it is so large it is not practical to browse.
Choosing to browse this database will take you to an advanced search screen where you
can restrict your search to CENTRAL alone. See page 20 for Advanced Searching.
This is the A-Z browse screen for the Cochrane Database of Systematic Reviews:
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1
1. The A-Z navigation tool
2. This allows various portions of the database to be displayed. The default will be all
records but some of the databases will allow you to choose subsets of records.
These options carry over to when you are viewing search results (see page 27).
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14. Cochrane Database of Systematic Reviews Symbols
On the Cochrane Database of Systematic Reviews you may also find the following
symbols after records, which have been changed with Issue 2, 2008:
A full review, complete with results and discussion, meta-
analysis and an odds-ratio diagram
This is an outline of a review in preparation, including
background, rationale and methods
A full-text systematic review of methodological studies
A full-text systematic review of studies assessing accuracy
of diagnostic tests
A new review or protocol that has been published in the
most recent quarter
A new search for studies and content updated (no change
to conclusions)
A new search for studies and content updated
(conclusions changed)
There has been an important change to the conclusions of
the review as published in the most recent quarter
The protocol has been amended to reflect a change in
scope as published in the most recent quarter
The review or protocol has been withdrawn, which may be
because it was considered to be out of date. Reasons for
withdrawal are specified in the article
The review includes comments. Readers can submit
comments which are incorporated into the review together
with answers and feedback from the review authors
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15. Browsing the Cochrane Database of Systematic Reviews
The Cochrane Database of Systematic Reviews can be browsed by topic, new or
updated reviews, A-Z or by Cochrane Review Group.
Browsing by topic
Use the drop-down list to browse review topics by your chosen Cochrane Collaborative
Review Group.
Selecting a review group shows the broad topic areas which that group covers. Clicking
on a heading opens out further sub-sections until you find a review of interest.
Click
Select your here to
chosen Cochrane see a
Collaborative complete
Review Group review
Browsing by review group
This brings up a list of the same review groups as searching by topic. But this time when
you select the name of the review group you are interested in you are presented with a
complete list of reviews for that group. This are split into protocols and reviews,
arranged alphabetically within each section.
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16. Searching the Cochrane Library
There are four ways of searching the Cochrane Library:
1. Simple search (see page 19)
Using the single search box on the home page is fine if you want to do a very quick,
one off search on a topic but you will not be able to build up a detailed or refined
search strategy.
2. Advanced search (see page 20)
Advanced search allows you to enter several search concepts in up to five search
boxes at one time. However we have found problems with this method and do not
recommend it.
3. Search history (see page 22)
Conducting searches from within search history allows you to build up detailed
search strategies by combining search statements together from a single screen.
Any searches you perform, no matter which method of searching you have used, will
be stored under search history for the duration of your current search session.
4. MeSH search (see page 24)
This is a specific method of searching using the index terms assigned to many of the
records in the Cochrane Library. It is best used in conjunction with free text
searching carried out within search history.
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17. Search tips and tricks
Unless you are searching using MeSH you will be entering your search terms in free-text
format. There are number of rules which will help you get the best out of the databases.
Combining terms The Cochrane Library supports the use of AND and OR to
using AND or OR connect search concepts together, eg
• postnatal and depression
• cancer or neoplasm
Hints:
Just as when you use a search engine such as Google,
typing in two or more words will automatically "AND" them
together, so the AND can be omitted, eg
• postnatal depression
Similarly, OR can be replaced by a comma, eg
• cancer, neoplasm
Phrase searching If you want two words to be adjacent to each other the phrase
must be enclosed in quotation marks, eg
• "postnatal depression"
Proximity connector Using the connector NEAR between words or phrases means
that they will appear within 6 or 7 words of each other (excluding
stop words), in any order, eg
• postnatal near depression
You can change how many words are between them, eg
• postnatal near/3 depression
Spelling tips Most plurals are automatically searched for, eg
• foot would also find feet
If you don't want to find the plural, type in the singular form in
quotation marks, eg
• "foot"
Common spelling variations are also automatically searched, eg
• randomise or randomize
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18. Wildcard/truncation The wildcard character is the asterisk *. It can be used at the
beginning, end or in the middle of words.
At the end of a word it acts as a truncation symbol to indicate
other letters that might appear after a word stem, eg
• diabet* would find diabetic or diabetes
Hint:
If you would only find the plural form of a word using
truncation there is no need as plurals are found automatically
(see above)
At the beginning of a word, eg
• *natal would find prenatal or antenatal or postnatal
In the middle of the words to pick up variations, eg
• hyp*tension would find both hypertension and
hypotension
Hint:
Although common spelling variations should be found for you
(see above), if you want to be sure that you have captured all
possible spelling variants, use the wildcard character, eg
• h*ematology would find haematology or hematology
The wildcard character should also be used to replace potentially
accented letters within words, eg
• “m*ni*re's disease” to find ménière's disease
Punctuation Hyphens are treated as spaces, so hyphenated and
unhyphenated forms of words will be searched for
simultaneously
• eg “body weight” will also find “body-weight’’
Other punctation, such as the apostrophe, are recognised, but
can equally be left out, eg either St John's wort or St Johns
wort both work fine
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19. Simple search
2
1
You can therefore conduct simple searches using the above search tips in the single
search box on the Cochrane Library front page:
1. Key in your search terms and click Go
2. As a default the Title, Abstract and Keywords fields are searched, but you can also
assign your search to other fields of the database, eg just the record title. For more
information about the various database fields see page 20.
Hint
If you use simple search for a search containing several search terms, including
synonyms, be sure to use brackets around terms to ensure that the search you want
runs smoothly. For example:
• ("otitis media with effusion" or "glue ear") and antibiotic and child*
It is vital to put brackets around the two synonymous terms to ensure that they are
OR'ed together. With complex databases such as the Cochrane Library, AND
commands will always run first within a search string, so without the brackets the
search would in effect be:
• "otitis media with effusion" or ("glue ear" and antibiotic and child*)
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20. Advanced Search
Advanced search allows you to enter several search concepts in up to five search boxes
at one time. However there are problems with this method and using Search History is
recommended in preference (see page 22).
• Click on Cochrane Advanced Search below the single search box on the home
page
You will see five interconnected search boxes and various options for restricting your
search.
Database fields
All text Your term in any field of all the databases. For CDSR this will be
the full text of the systematic review.
Record title Article titles only
Author Authors of articles only
Abstract Abstracts only
Keywords Your term in the Index field in all databases except "About" which
don’t have an index field. All of the databases except CMR use
MeSH as their index terms. CMR uses its own index terms called
CMR words. CDSR, CENTRAL and NHS EED additionally use
MeSH check words.
Title, Abstract Your term in any of the fields, title, abstract or keyword.
or Keywords
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21. Tables Your term in the Table field. Tables only appear in the CDSR
database.
Publication type Searches the Publication field in CENTRAL only. The following
possible terms used are: clinical trial; journal article; multicenter
study; randomized controlled trial; controlled clinical trial.
Source Searches the title field or the field which details the source of the
original article referenced in the database.
DOI A search for the DOI number in the DOA field of CDSR. (DOI
means Digital Object Identifier see www.doi.org/faq.html#1)
Restrictions and limits
You can also choose to:
• Restrict your search to particular databases within the Cochrane Library
• Select just new, updated, commented or withdrawn records (this applies to CDSR
only)
• Select a date range for your search
There is little value in restricting your search to individual databases because search
results are split by database allowing you to choose which set of results to look at.
Rather, the structure of the database you are most interested in should dictate the
search method you use.
On the whole we would recommend not using Advanced Search. This is because of the
misleading way in which terms are combined between the five search boxes. Just as
with the hint on using Simple Search on page 19 if you do use Advanced Search be sure
to incorporate all synonyms within a single search box and not split them up.
For example, do not construct a search statement such as:
"otitis media with effusion"
OR "glue ear"
AND antibiotic
AND child*
Instead, you should construct it as:
"otitis media with effusion" or "glue ear"
AND antibiotic
AND child*
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22. Search history
Clicking on Search History below the single search box on the home page takes you to
a much simpler search page than Advanced Search with a single search box.
The purpose of using Search History is to build up a search strategy consisting of
several search statements and then use commands to combine those individual terms
together. This forces you to think carefully about the construction of your search
statement. It encourages you to search for one term, or concept, at a time, and
additionally allows you to combine free text searching with MeSH searching (see page
24) to build up a thorough search strategy.
In addition to your search term you can
• Select just new, updated, commented or withdrawn records (this applies to CDSR
only)
• Restrict your search to a particular database
• Select a date range
Searching fields
You can now include field “labels” as part of your search statement to find the
occurrence of words or phrases in particular fields such as the title or author. Available
field labels are:
Field Name Label
Abstract :ab
Author :au
Keywords :kw
Source :so
Title :ti
Publication Type :pt
Tables :tb
DOI :doi
If no field tag is specified, “All text” is
searched as the default
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23. The following chart gives specific examples of how field labels can be used within a
search.
Options Example Action
Diabetes Searches diabetes in ALL text fields
No field tag
(current default)
One field tag Diabetes:ti Searches diabetes in title field
Diabetes:ti,ab Searches diabetes in title OR diabetes
Multiple field tags
in abstract
Supports truncation diabet*:ti Searches diabet* in title
“diabetes Searches the phrase diabetes mellitus
Supports phrase search
mellitus”:ti,ab in the title or abstract field
Supports phrase search (Diabetes next Searches the phrase diabetes mellitus
using NEXT operator mellitus):ti,ab in the title or abstract field
(diabetes near Searches for diabetes within 6 words
Supports NEAR operator mellitus):ti,ab (established default) of mellitus in the
title or abstract field.
(diabetes near/5 Searches for diabetes within 5 words of
Supports NEAR/x operator
mellitus):ti,ab mellitus in the title or abstract field
Support for more than one diabetes.ti and Searches diabetes in article title and
term in a search having endocrinology.so endocrinology in source
field labels
• Simply key your search term into the search box and click go
This is in example of a free text search where three concepts have been searched for
individually:
2 1
1. The red numbers tell you how many results (hits) have been found for each search
term. You can also edit or delete individual search lines.
You will now want to combine these three search concepts together to find items
mentioning all of them.
2 .Notice the ID column where each line of the search has been given a number, eg #1.
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24. 3. It is these numbers, including the #, that you use to combine terms together
4. When searched, this combination also appears in the Current Search History
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Searching MeSH
This is a specific method of searching using the index terms assigned to many of the
records in the Cochrane Library. It is best used in conjunction with free text searching
carried out within Search History.
MeSH stands for Medical Subject Headings which is the name given to the thesaurus
(the system of indexing terms, or descriptors) found on the Medline database.
So far we have just searched in a free text style. This is generally fine when looking for
information in the full text databases on the Cochrane Library, namely CDSR and to a
lesser extent DARE. However, the other databases only provide you with abstracts
rather than whole documents. Therefore the most efficient way of searching CENTRAL,
HTA, NHS EED and DARE is to use, in conjunction with free text searching, the index
terms assigned to these articles, because you cannot guarantee that your chosen terms
will appear within the abstract itself.
You can get directly to the MeSH search option from the Cochrane Library home page
below the simple search box or access it from within Search History.
Below is a very simple free text search, conducted within Search History, for records
about the use of acupuncture to help people stop smoking.
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25. You will now want to incorporate the relevant MeSH terms for your two concepts into the
search.
• Click on MeSH Search
• Key in the term you want to match into the search box and click Thesaurus. This will
search for likely terms within the indexing system.
Click here for Thesaurus
1. Select the most appropriate term from the list
2. One or more trees of terms will appear. You can choose to search within a
specific tree or all trees where your term appears. The default is all trees
and explode. Explode will thereby also search for any narrower terms
which you may see below your term and indented to the right. You can only
Explode all trees. The latter is generally recommended
3. You can also either search only your chosen term (the one in red).
4. If you tick the box Go directly to Search History you will be taken directly
back to the Search History screen once you have clicked View Results,
allowing you to enter further terms or to start combining terms.
4
1
2
3
Once you have repeated this process for each search concept you are in a position to
combine your free text and MeSH searches together, or indeed just combine the MeSH
terms together:
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26. 5
5. Notice the use of OR to join together the free text and MeSH versions of each
concept.
You will notice that there are fewer results just using the MeSH headings. This will be a
much tighter, more focused search, and so long as the records on the database have
been indexed correctly and consistently, should give you very relevant results. If you are
specifically interested in trials this is a good method of searching CENTRAL.
Using a combination of free text and MeSH terms will, on the whole, provide you with a
larger number of results. While this method does ensure that you don't miss anything
you will also pick up irrelevant results.
Adding qualifiers
1. You may also add Qualifiers to your search terms. Qualifiers narrow your search to
specific aspects of a topic, eg diet therapy, rehabilitation, complications,
ultrasonography.
1
NB You can also search by qualifier alone, eg for the qualifier rehabilitation which
could be attached to any thesaurus term.
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27. Viewing, printing and saving search results
Viewing results
To view your search results from within Search History click on the relevant search
statement of the set you want to look at it, eg #7 and #8.
No matter which search method you have you used you will be automatically taken to a
list of results in the Cochrane Database of Systematic Reviews, or the first database in
which results appear (unless you have restricted your search to a particular database).
1
4
5
3
2
1. You will also be able to see how many records have been found in each of the other
databases. Click on any of these database headings to switch to the results from
that database.
2. Records are automatically displayed by Record Title, ie alphabetically, but you can
re-order them to be displayed by Year, with the most recent items first, or by Match
%, in order of likely relevance.
3. Again, you may restrict the records displayed in this particular database to completed
reviews or protocols.
4. You may also have the option to Save Search or Edit Search. You will only see
these options if you are viewing a single search statement which is not reliant on any
other search statement. In the search example above this would apply to #1, #2, #4
and #5 but not the other lines of the search because they combine other search
statements together.
Choosing to edit a free text search statement will take you to an Advanced Search
screen. Choosing to edit a MeSH search will take you back to the MeSH search
screen.
You will only be able to save the search if you are logged on to your account. See
page 32 for more information on saving searches.
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28. 5. To view a complete record click on Record
You will see that the screen is now split in two, with the text of the systematic review on
the right (starting with an abstract and synopsis) and an index of the contents on the left.
This method of navigation applies to all the main databases with the exception of
CENTRAL and CMR.
2
1
The contents index has been re-organised and each heading is listed and explained on
page 29. Each section heading now appears in italics, Quick links; The review;
Supplementary information; About this article
1. The section Authors' conclusions will give you a baseline outcome of the study split
into implications for practice and implications for research.
2. You should always check the date of the review, or its last update at the top of
the review. If you are looking for the most up to date information on a topic there
may have been new trials published, which you will find on CENTRAL, since the review
was published.
You can also look at the Index terms with which the review has been indexed which
may help you to find similar studies.
Comments about the systematic review can be added via Submit Feedback, and any
replies from the authors read in Feedback.
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29. Different sections of a Cochrane Systematic Review
Abstract A structured abstract for the review, giving brief information on
its background, objectives, search strategy, selection criteria,
results and authors’ conclusions
Plain language Summarises the findings of the review in one paragraph
summary
Quick links
What’s new Details when published, updated and historical information of
the review
The review
Background An overview of the condition and treatment on which the
evidence is being reviewed
Objectives Aims of the review
Methods The types of study, participant, intervention and outcome
measures that were required for a study to be required
Results Detailed description of studies’ findings
Discussion What the results show
Author’s conclusions Gives a baseline outcome of the study, split into implications for
practice and implications for research
Acknowledgements Acknowledgements of people who helped the authors
References References to studies included and excluded from the review
Figures Other charts included in the review
Tables Tables of results
Supplementary
information
Data and analyses Statistical analysis tables
Appendices Featuring relevant additional information and documents
Feedback Replies from authors concerning any feedback queries from
this review
About this article
Contributions of Indicate which authors contributed to which part of the review
authors
Declarations of interest Any potential conflict of interest on the part of the reviews
authors
Sources of support List of any internal or external sources of support provided to
the review’s authors
Index terms Look at the terms with which the review has been indexed to
help find similar studies
Submit feedback Comments about the systematic review can be added here
Export citation A tool to export your citation into a tool such as Reference
Manager
Protocol and previous Any protocols and earlier versions of this review
versions
29

30. Following up primary references
If you go to References and click on Links beside an article reference you may be taken
to a further link providing you with title and abstract information (note, not full text) for
that primary reference in PubMed which is the freely available online version of the
Medline database.
Interpreting graphs
A key component of the systematic review is the statistical method of combining the
results of different primary studies that look at the same intervention. This is known as
meta-analysis and the results of a meta-analysis are usually shown in one or more odds
ratio diagrams.
At first glance they can be rather frightening but you don't need an in-depth
understanding of statistics to be able to interpret them quite simply.
This odds ratio diagram looks at the outcome of smoking cessation after 6 months
comparing sham acupuncture (the control) with real acupuncture (the treatment).
The odds ratio for each individual trial is shown by a blue square. The horizontal line
through it represents the confidence interval for that result.
The meta-analysis result is shown by the black diamond the width of which represents
the confidence interval. Confidence intervals are usually shown as 95% confidence
intervals, representing the range in which we can be 95% confident that the real result of
the study lies.
The vertical line through the diagram at the odds ratio of one is known as the line of no
effect. Anything crossing this line cannot show whether the intervention is any better or
worse than the control. But results that fall to the left of the line indicate less of the
outcome in the experimental (treatment) group and results to the right of the line indicate
more of the outcome in the treatment group. Just be aware that more of an outcome is
not necessarily a good thing, ie when you are measuring mortality.
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31. Saving and printing search results
You can print entire records, including the very lengthy systematic reviews, if you view
them as PDF files. Simply use the integral print and save icons within Adobe Acrobat.
Otherwise you can print, or save to file, selected citations.
1
2
3
1. Put a tick in the box beside the individual references you are interested in or click
select all at the bottom of the list
2. Select all will pick up the entire search set from the database you are viewing but
you can select records from different databases and export them together.
3. Click Export Selected Citations
This screen will appear:
1
2
1. You can choose to select just the Citation or Abstract and citation from the drop
down Export Type box
2. Click Go
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32. You will then be asked whether you want to open the file on your computer now or to
save it to your hard drive or a floppy disk.
N.B. There is a distinction made on the Cochrane Library between Save Search and
Save Search Strategy.
Saving a search allows you to save individual search statements, or lines of a
search
Saving a search strategy allows you to save a string of search commands
Saving your search
You will see this option when you are viewing the results of individual search statements.
1. Click on Save Search. If you are not already logged on you will be asked to enter
your username and password.
1
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33. Saving your search strategy
Saving a search strategy allows you to save a string of search commands
1. You may save your search strategy from within the Search History function as long
as you are logged on to your account.
2. You may also clear your history at any point.
2
1
Once you have clicked Save Search Strategy the dialog box below appears for you to
enter the name of your search and any comments.
1
1. Then click Save Search Strategy
The next time you log on the Cochrane Library you will be able to access your saved
searches and search strategies by clicking Saved Searches below the simple search
box on the home page or from within whichever search mode you are in.
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34. Saved searches do not currently appear in the My Profile banner at the top of the
screen.
1 3
2
1. To run the search click Run
2. To delete any saved searches, check the tick box(es) and click Delete Checked
Items
3. To export your saved search, click export. This allows you to download a copy of
your search strategy to include it in a word processing document. Select either
open or save
Each line of your search will be displayed separately. The file is in .txt format, as shown
below.
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35. Setting alerts
Currently, alerts may be set for individual search statements, not full search strategies.
To activate the alert
click on this link
• If your search can be set as an alert you will see Activate Alert beside it.
• To cancel an alert click on Stop Alert
You will be sent an email to the address you gave when you set up your profile if new
records matching your search criteria are added to the database at subsequent quarterly
updates.
You may set various options for your alerts by clicking My Profile in the banner at the
top of the screen.
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