in Trials (Word variations have been searched)

Using Search Functionality

This tab provides information on the most commonly used features for the tab being used. For complete information on New Search including demonstrations, information on error messages, and FAQ's, click here

Using Search Tab

Use the Search Tab to perform quick searches of the Cochrane library using just a few terms. Also for experienced searchers who prefer to use pull down menus to search using field labels. Includes auto-suggest feature and supports up to five search rows.
Search Basics

Search – Advanced Options

Search commands and syntax

Limit by Field

Use pull down menu to limit searches to specific fields (title, abstract, keywords, and authors). Default is set to title, abstract and keywords to ensure most relevant articles are found. If search retrieves too few articles, try changing limit to “All text”.

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Entering Search Terms

  • Enter search term(s) in box. By default on Search Tab, common variants of the word are searched.
  • If two or more terms are entered, search will “AND” terms and find articles or selected fields where both terms appear.
  • To search a phrase, put terms in quotes, “lung cancer” searches for that specific phrase.
  • Selecting phrases using auto-suggest will automatically add quotes and search as a phrase.

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Term Search: Using term variants (automatic stemming)

When a term is entered, the search automatically finds its word variants (listed below) eliminating the need to enter common variants.

  • Linguistic variants: clear finds clear, clears, cleared, clearing, clearer, clearest
  • Common British vs. American spelling variants: tumor also finds tumour
  • Non-standard plural variants: mouse also finds mice
  • Common irregular verbs: run also finds ran, runs, running

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Term Search: Without using term variants

Automatic stemming can be shut off by putting the term in quotes and selecting the “Word variations will not be searched” box in the Search Limits. This feature is also disabled if search terms include wildcards (* or ?)

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Searching Multiple terms

When entering two or more terms without quotes, search will “AND” all terms. Finds articles where all terms must appear in the article (or selected fields).

Example: lung cancer (finds articles containing lung and cancer anywhere in the article)

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Phrase Searching

To search for a phrase, put terms in quotes. Phrase search does NOT support the use of wildcards.

Example: “diabetes mellitus” (finds the phrase diabetes mellitus in the article or selected fields)

Example: “Food and Drug Administration” (finds phrases that contain a Boolean operator (AND, OR, NOT))

Example: hearing NEXT aid* (If using wildcards, use NEXT operator).

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Viewing Results

To view results, hit the “Enter” key or click the “Go” button. Results will be displayed at the bottom of the page. In the left hand column of the results, the radio button will indicate which database results are being displayed. The numbers in parentheses after the database names show the number of articles found for your search in that specific database.

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Use the Search Limits button to limit by database, status, review group or date. There are two dates to choose from:

  • Publication Year: This is the year that the document was originally published. For a Cochrane Review which has been updated, this is the year of the last significant update.

  • Cochrane Library Online Publication Date: This is the date (month / year) that the Cochrane Review was added or last updated on the Cochrane Library.

If you only have Cochrane issue and year and not the month and year information, refer to the Cochrane Library Online Load dates for each issue.

Click “Apply” to select limits and “Go” to run your search using these new limits.

To apply a limit to all articles in The Cochrane Library, place * in the search box and select your limits.

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Insert or Delete a line

Use the [+] and [-] buttons to add or delete search lines. Up to 5 lines can be added on the Search Tab. To develop longer and more complex search strategies it is recommended that you use the Search Manager Tab.

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Adding a Search to Search Manager

For users want to build complex searches in Search Manager, after entering your terms and applying all desired limits, use the “Add to Search Manager” button to add your Search to the Search Manager.

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Saving Search

Individual Searches can be saved by entering term(s), running the search and using the “Save Search” button. To save searches, a user must be registered with the Cochrane Library and be logged in to their account.

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Running a Saved Search

To run a previously saved search, a user must be registered with the Cochrane Library and be logged in to their account. Go to the Saved Searches section under the Search Tab and click on the arrow, ►, to see All Saved Searches. Select the load button, , to run the search. Note: The Saved Search section appears only if user has one or more saved searches.

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Setting (and turning off) a Saved Search Alert

For Saved Searches, users can set an alert so they will receive an email every time new articles indexed with their search terms are published in the Cochrane Library. To set alerts, a user must be registered with the Cochrane Library and be logged in to their account. To set an alert, go to the Saved Searches Section and click on the arrow, ►, to see All Saved Searches. Find the search you wish to set the alert for and click the checkbox at the end of the search line. A check in the box means the alert is on, remove the check to turn off alerting.

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Boolean Operators: Using AND, OR, NOT

Boolean operators can be selected from the pull down menus or directly keyed Supports use of AND, OR, NOT to combine search terms.

Both terms MUST appear in the article or selected field(s).

Example: insulin AND diabetes

At least one of the terms MUST appear in the article or selected field(s).

Example: heart OR cardiac

The first word must appear but the second word cannot appear in the article or selected field(s).

Example: aids not hearing

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Proximity Operators: Using NEAR and NEXT

Supports use of NEAR, NEAR/X and NEXT. Finds terms within close proximity to each other in the article or field(s) being searched

Finds the terms when they are within 6 words of each other. Terms can appear in either order.

Example: cancer near lung (finds lung cancer as well as cancer of the lung)

Finds the terms when they are within X words of each other where X = the maximum number of words between search terms. Terms can appear in either order.

Example: cancer near/3 lung (finds lung cancer, as well as, cancer of the lung)

Finds the terms when they appear next to each other. Terms must appear in the order specified. Use for phrase searching with wildcards.

Example: lung next cancer (finds lung cancer but not cancer of the lung)

Example: hearing NEXT aid* (finds hearing aid and hearing aids)

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Order of Precedence

If a search contains more than one Boolean operator and it does not use nesting, the system will perform the operations in the following order:

  • All NOT operations first
  • All AND operations second
  • All OR operations last

For better precision, use nesting to specify order of operations.

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Nesting (or grouping terms)

Use parentheses () to explicitly group searches using Boolean or proximity operators and to change the default precedence order.

Example: (kidney OR renal) AND dialysis

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Using Wildcards (truncation)

Use to find terms containing a common word root. Use * to search for one or more characters, and ? for single character. A wildcard can be added to the right (end of term), left (beginning of term) and internal (within) a term, however the word root must be at least 3 characters.

transplant* Use an asterisk (*) to match all terms beginning with a word root.
Finds transplant, transplants, transplanting, transplantation, and transplantable.

*glycemia Use an asterisk (*) at the beginning of a word to match terms with the same suffix.
Finds hyperglycemia or hypoglycemia.

leuk*mia Use an asterisk to match multiple characters within a word.
Finds both leukemia and leukaemia.

wom?n Use a question mark (?) to match a single character within a word.
Finds women or woman.

system? Use a question mark to match all terms beginning with the word root + one additional character.
System? Will match system and systems but not systematic or systemic.

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Searching Field

Limit to specific fields using the pull down menu.

Use this label to limit search to terms in the article title

Use this label to limit to the Abstract field

Use this label to limit to Keywords. Limit includes MeSH terms but does not allow for MeSH term explosion. Also searches EMBASE keyword fields

Use label to limit a search to the author field

Publication Type
Use this label to limit to Publication Type. Used only in CENTRAL

Use this label to limit to the Title of journal, conference name, report name, etc.

Use this label to limit to the Captions of tables

Digital Object Identifier (DOI)
Use this label to limit a search using a DOI. Must search using the entire number

Accession Number
Use this label to limit a search on text or id numbers found in the Accession Number field in some CENTRAL articles. It will allow users to search based on the source database, Pubmed or Embase, or accession number ID, e.g. 2006328324.

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