Searching the Cochrane Library

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Searching the Cochrane

Library

Acute

Primary Care & Community

Marisa Martínez-Ortiz

Marie Hounsome

Knowledge Skills & Systems

Outreach Clinical Support

Librarian

Tel: (01293) 600431

Internal x3431

Mob: (07787) 531918

maria.martinez-ortiz@sash.nhs.uk

marie.hounsome@sash.nhs.uk

www.surreyandsussex.nhs.uk/lis

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Learning objectives

At the end of this session you should be able to:

• Identify when to use Cochrane

• Log on to the Cochrane Library databases from home and work

• Formulate a search string, using basic Boolean logic

• Search using Keywords and MeSH terms

• Use the search history function to combine search results

• Refine search criteria by author or title

• View records from each database and navigate through a review

• Print records from each database

• View graphs and tables from a review

What is the Cochrane Library?

The Cochrane Library is a database of reliable evidence on the effectiveness of

healthcare interventions. It is regarded as the best resource available of this

type. The Cochrane Library is put together by the Cochrane Collaboration, the

NHS Centre for Reviews and Dissemination and other related organisations and

is updated quarterly.

When should you use the Cochrane Library?

The Cochrane Library should be used when looking for the best evidence on the

effectiveness of treatment and health promotion interventions. The best type of

evidence comes from systematic reviews and randomised controlled trials

(RCTs). It is also a source of information on the methodology of systematic

reviews.

It should be used when looking for information on the effectiveness of an

intervention, for example:

• What is the effectiveness of treatment y?

• What is the effectiveness of treatment x in condition z?

• Is treatment y better than treatment x?

• Are there any systematic reviews of stroke rehabilitation effectiveness?

The Cochrane Library should not be used for the following:

• General healthcare information

• Guidelines for clinical practice or audit procedures

• Primary research (other than systematic reviews and randomised

controlled trials)

• Questions relating to the cause, prognosis, epidemiology or risk factors for

an illness or disease1

1 Ask your local health librarian if you need advice on where to search for this type of information

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Overview of the Cochrane Library databases

The Cochrane Library consists of several different databases:

The main databases

• Cochrane Database of Systematic Reviews (Cochrane Reviews)

Database of completed, full text systematic reviews carried out by the

Cochrane Collaboration, plus ‘protocols’ (reviews currently in progress)

• Database of Abstracts of Reviews of Effectiveness (Other Reviews)

Database of structured abstracts of other systematic reviews from

alternative sources of literature

• Cochrane Central Register of Controlled Trials (Clinical Trials)

Detailed references to randomised controlled trials identified through

searching databases such Medline and Embase, as well as hand

searching journals

Other databases

• Cochrane Database of Methodology Reviews (Methods Reviews)

Contains full text, ongoing and completed reviews of methodological

studies

• Cochrane Methodology Register (Methods Studies)

Bibliography of publications on how to conduct reviews and trials

• Health Technology Assessment Database (Technology

Assessments)

Database of information on healthcare technology assessments

• NHS Economic Evaluation Database (Economic Evaluations)

Database contains structured abstracts of articles describing economic

evaluations of healthcare interventions

• About the Cochrane Collaboration (Cochrane Groups)

Contains information about the work of the Collaboration and lists the

Cochrane Review Groups with their contact details.

When you search the Cochrane Library, you will search all the databases at

once. You are able to decide which database you want to view the results in.

Accessing the Cochrane Library

1. The Cochrane Library may be accessed from the Library website at:

www.surreyandsussex.nhs.uk/lis (or if you are in East Surrey or Crawley

hospitals click on Library Service from the Intranet and click on Electronic

resources. Click on Cochrane Library).

2. Or directly from: www.thecochranelibrary.com

Access is available to everyone, without requiring a username and password. It

is possible to create an account if you wish to save your searches.

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Planning your search

Before starting any search you should first decide exactly what you want to

search for and from what perspective. A useful method of doing this uses the

acronym PICO2:

Patient, problem or population

Age, sex, race, condition or disease,

care setting, etc

Intervention

Type of intervention e.g. test, therapy

or clinical procedure

Comparison

Alternative interventions, if applicable

Outcomes

Measurement, result, effect

This will allow you to form your search strategy and give you keywords.

For example, if you are looking to find out whether antibiotics are effective in the

management of severe asthma, the keywords you would need to search for are

antibiotics and asthma

Conducting a keyword search

A keyword search will search for a particular word or phrase anywhere in the text

of documents in all the databases.

When keyword searching it is necessary to consider as many alternative terms

and synonyms as you can for your topic (e.g. Heart attack, Myocardial infarction,

MI etc.)

To keyword search, select Advanced Search.

2 PICO can be a helpful tool, but should not dictate your search.

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Enter the term(s) in the search box.

To search for reviews or trials with your search terms anywhere in the text select

Search All Text from the drop down menu.

Click on Search to carry out the search.

You may find a lot of ‘false hits’ (documents which contain your search terms in

the text but these terms are not the main focus of the review).

To search for reviews or trials which have your search term in the title, abstract

or as ‘keywords’ select Title, Abstract, Keywords from the drop down menu.

Each database will then indicate the number of references found.

Search Tips

• To search for a phrase you must enter it in quotes e.g. “smoking

cessation”

• Truncation can make keyword searching more effective and

comprehensive. Use the * symbol at the end of a word to search for

different endings e.g. depress*. (Will search depression, depressed etc.)

• Internal truncation may also be used to search for different spellings e.g.

p*diatric. (Will search paediatric and pediatric)

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MeSH (Medical Subject Headings) Searching

MeSH is a controlled thesaurus. It is used to index articles on the same subject

in the same way. When you search using the database’s thesaurus you will only

retrieve records that are about that subject, not those which merely mention the

word. This means that you will retrieve more relevant results.

In order to conduct a comprehensive search it is best to search using both

keywords and MeSH.

To search using MeSH click on MesH Search from the front page or from the

Cochrane Advanced Search page.

Advanced Search | MeSH Search | Search History | Saved Searches

Enter your term in the search box, and click on Thesaurus. This brings up a list

of terms, select the one most appropriate.

Search term or explode

Search this term only will select the main heading (in this case Asthma).

Explode will broaden your search to include any narrower terms (in this case

Asthma, Exercise-Induced and Status Asthmaticus).

Explode

All

Tree Number 1

Tree Number 2

Tree Number 3

Tree Number 4

Search this term only

Tree Number 1

Respiratory Tract Diseases [+14]

Bronchial Diseases [+10]

Asthma [+2]

Asthma, Exercise-Induced

Status Asthmaticus

Bronchial Fistula

Bronchial Hyperreactivity

Bronchial Neoplasms

Bronchial Spasm

Bronchiectasis [+1]

Bronchitis [+2]

Bronchogenic Cyst

Bronchopneumonia

Tracheobronchomegaly

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Click in the Go directly to search history box and press View Results to be

taken to your search history so far.

Your search history will appear displaying a list of the searches done so far. To

view the results click on the link.

Combining results

The Cochrane Library gives three options to connect your search results

together:

AND will combine all terms

OR will combine similar terms into one big group

NOT will exclude term from the search

To combine, enter #(line number) and #(line number) in the search box

e.g. #1 and #2. Then click on Go

Search For:

#1 and #2

The combined results will appear in your search history. To view the results of

your combined results click on the link

Current Search History

ID Search

Hits Edit Delete

#1 asthma in All Fields, from 1800 to 2005 in all products

13371 edit delete

#2 MeSH descriptor Anti-Bacterial Agents explode all trees in MeSH products 12911 edit delete

#3 (#1 AND #2)

edit delete

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Displaying Results

To view results from a particular database, click on the title of that database.

Click on Record to open the review you want and the review will be displayed in

full on screen.

Click Record to see full text

Select database to view results

The symbol indicates a full review is available

The symbol indicates a protocol (the review is still in progress)

Reviews can be long, use the headings of the review, which are outlined in the

index on the left hand side of the screen, to navigate your way through the

document. To return to your list of records click on your browsers Back button.

To see the conclusions of the review click on Authors’ / Reviewers’

conclusions

• Results

• Discussion

• Reviewers' conclusions

To display the meta-analysis of trials data click on Figures (full size)

Figures (full size)

Tables

Printing

Cochrane Systematic reviews may be opened as a pdf file and then printed.

Click on PDF at the top of the index on the left hand side of the screen.

[Review]

Continuous passive motion following total knee arthroplasty

PDF (Size 343K)

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NOTE: some systematic reviews are very long! You may only wish to print

selected pages. To do this highlight the section you wish to print, go to File,

Print, and from the Page Range section select Selection. Click on Print.

Limits

There are some options for limiting your searches. Click Advanced Search.

Using the drop down arrows refine your search by Author, Record Title, and

Source.

The Date Range limit is further down the screen.

AND

antibiotics for severe asthma

Record Title

AND

lasserson

Author

AND

Abstract

AND

Keywords

Date Range

1800

2006

(4-digit years, or '*' for any year)