How do I create a simple NLM Catalog search?

Enter one or more terms in the search box and click Search. Search terms are automatically ANDed together.

What is the difference between the NLM Catalog and LocatorPlus?

The NLM Catalog provides access to NLM bibliographic data for over 1.4 million journals, books, audiovisuals, computer software, electronic resources, and other materials. It contains detailed MEDLINE indexing information about the journals in PubMed and other NCBI databases.

LocatorPlus is the web-based public access catalog component of the Voyager system used at NLM. It contains information on NLM’s holdings, circulation status, and access to the records in MARC format. Users can access a title’s LocatorPlus record from the Full or Journal display options.

The NLM Catalog will serve the needs of the majority of users. Users searching for information about NLM’s holdings or the circulation status of a title, or users who are interested in the MARC format should view the title’s LocatorPlus record.

Can I import records from the NLM catalog into my reference management program?

Currently users cannot import records into reference management programs directly from NLM Catalog. There are two options available to import references:

1.

Link to LocatorPlus and use the “Bibliographic management” selection in the save option.

2.

Create a custom import template in your reference management software. Most commercial reference management software packages include the option for creating custom templates. Contact the producer if you have specific questions about their product.

I found an error in the NLM Catalog. Where do I send a correction?

Please send corrections to NLM Customer Service, custserv@nlm.nih.gov

Searching by title

Enter one or more words from the title, with each word followed by the field qualifier [ti].

Searching by author

You can search for either the name of an individual author (Personal Name) or for the organization (corporate name) or conference which is considered the author of a work.

Searching by subject

Subjects in NLM Catalog records include Medical Subject Headings (MeSH) terms, Personal Names, and Other Subjects.

Eye [A01.456.505.420]

Phrase Searching

When a phrase is entered as the search term, it is checked against the translation table used in Automatic Term Mapping. When a match is found, it is searched as a multi-word search term.

When a phrase is not automatically identified in the table, you can request a check for the phrase in the NLM Catalog's index of searchable terms. Either enter the phrase in quotes, e.g., "single cell," or qualify the phrase with a search tag, e.g., single cell[ti]. When a phrase in double quotes is found in the index, it is searched as a multi-word search term and automatic term mapping is not applied. There is no explosion of MeSH terms.

Note: If your search phrase is not in the index of searchable terms, the individual terms in the phrase are processed using automatic term mapping and all terms are ANDed together.

Send suggestions of phrases to add to this index to NLM Customer Service.

Searching with field qualifiers

Search for information in specific fields by adding the Search Field Label in square brackets after the search term. The qualifiers can be in upper or lower case.

Combining search terms with Boolean operators (AND, OR, NOT)

The NLM Catalog applies an AND operator between concepts, e.g. “vitamin c common cold” is translated as vitamin c AND common cold. Enter Boolean operators in uppercase characters to combine or exclude search terms:

• AND retrieves results that include all of the search terms.
• OR retrieves results that include at least one of the search terms.
• NOT excludes the retrieval of terms from your search.

Note: The NLM Catalog processes searches in a left-to-right sequence. To change the order in which the operators in a search statement are processed, enclose search terms in parentheses. The terms inside the set of parentheses are processed as a unit and then incorporated into the overall search strategy.

Click Details on Advanced Search or see the Search details portlet to see how the NLM Catalog translated your search strategy.

Truncating search terms

To search for all terms that begin with a word, enter the word followed by an asterisk (*), the wildcard character.

More information about truncation:

• This truncation feature is limited to the first 600 variations found. If the search retrieves more than the 600 variations, a warning message displays to lengthen the root word to search for all endings.
• Truncation turns off automatic term mapping and the process that includes the MeSH term and any specific terms indented under that term in the MeSH hierarchy. For example, heart attack* will not map to the MeSH term Myocardial Infarction or include any of the more specific terms, e.g., Myocardial Stunning; Shock, Cardiogenic.
• Truncating a word in a multi-word search may result in an unexpected phrase search. For example the search, fetus infection* maternal will treat fetus infection* as a phrase.

Previewing the number of search results

Use the Preview button in Advanced Search to preview the number of citations before displaying the search results:

1.

Click Advanced Search.

2.

Enter your search term(s) in the search box.

3.

Click Preview to display the number of results in Search History.

4.

To display the results, click the Search History result link.

Browsing the index of terms

The Advanced Search Search Builder Index provides an alphabetical display of all terms in each NLM Catalog search field.

1.

Click Advanced Search

2.

Use the Search Builder to select a search field from the All Fields menu.

3.

Enter a term in the search box and click Show Index.

4.

Select a term. To select multiple terms (and OR them together), select each term while holding down the Ctrl key (PC) or the Command key (Mac).

5.

Click the Add to Search Box button to add terms to the search box. Repeat steps as necessary.

6.

Click Search.

Combining searches using History

Previous searches can be combined or used in subsequent searches using the search statement number from the Search History on the Advanced Search page.

• Click Advanced Search
• In the Search History section, click the search statement number to display the options menu that includes Boolean operators to AND, OR or NOT your search to the search box. Alternatively you can enter a number sign followed by the search number, e.g., #1, in the search box.
• To view the results of a search, click on the result number.

Publication Type

The Publication Type limit restricts your search based on the type of physical format (items) and resource types. The Limits page displays a list of the most frequently used publication types:

• Conferences
• Consumer Health
• Dictionary
• Directory
• Handbooks
• Practice Guideline
• Review

Scroll down in the Publication Type box to display a more comprehensive list under “More Publication Types” or see Table 1. For a publication type not on the Limits page, enter it in the query box, qualified by the search field name [pt].

Table

Table 1 List of Publication Types

Material Type

The Material Type limit restricts your search to a particular item or resource type. The Limits page displays the most common material types:

• Books
• Book Chapters
• CD-ROMs/DVDs
• Images
• Internet
• Journals (All)
• Journals (Currently published)
• Manuscripts
• Videorecordings

For a material type not on the Limits page, enter it in the query box, qualified by the search field name Item Type [item] or Resource Type [res type].

Languages

The languages limit restricts your search to materials in a particular language.

The Limits page displays a list of the most frequently used languages:

• English
• French
• German
• Italian
• Japanese
• Russian
• Spanish

Scroll down in the Languages box to display the complete list under “More Languages.”

You may also search for a language by entering the language name in the query box and qualifying it with the search field tag [la].

The complete list of languages used is based on the official list of languages provided in the MARC Code List of Languages, a standard maintained by the U.S. Library of Congress.

Journals Referenced in the NCBI Databases

This limit allows you to restrict your search to the subset of journals that are referenced in the NCBI Databases, including PubMed. This limit can also be activated by searching from the Journals Referenced in the NCBI Databases page.

Note: See more information on searching for journals in the NLM Catalog.

Journal Subsets

The Journal Subsets limit allows you to restrict your search to various subsets of journals in the NLM Catalog.

• Only PubMed Journals
• Currently indexed in MEDLINE
• Currently or previously indexed in MEDLINE
• PubMed Central Journals
• PubMed Central Forthcoming Journals

Scroll down in the Journal Subset box to display additional subsets for currently indexed journals. Also see the list of journal subsets in Table 3.

Table

Table 3 Journal Subsets

Note: See more information on searching for journals in the NLM Catalog.

Full Text

To limit your search results to only journals that include links to full text, click the “Link to Full Text” box.

Publication Year

Use the "From" and "To" boxes to specify a range of dates. For a single year, enter the year in both boxes. If no date is entered in the "To" box, the NLM Catalog searches the date in the "From" box through the Year 3000. If no date is entered in the "From" box, the NLM Catalog searches all dates preceding the one in the "To" box, starting with year 1.

NLM Collection

To limit your search results to items owned by the National Library of Medicine, click the “NLM Collection Only” box. For holdings information, view the LocatorPlus record by using the link on the record’s full display (the NLM ID or NLM Holdings icon). The link opens a new window to display the record.

Search Field Tags

Choose a specific search field tag to limit all terms in the search box to that field.

Changing the display format

Results are initially displayed in the Summary format, except results for a single item display in the Full format. You can change the display for all or selected records by selecting a format from Display Settings.

To change the display format only for selected records, click the check box to the left of each record before selecting a display format.

See Table 2 for a description of all the display formats.

Table

Table 2 List of Display Types

Changing the number of items per page

From Display Settings, select the number of items per page to display. You can change the number of records displayed on a single page from 5 to 200 items.

Sorting your search results

From Display Settings, select a sort by option. Sort options include: Publication Date, NLM ID, Author, Title, Title Abbreviation, and Country of Publication. The default sort option is Publication Date, which displays in descending order.

Saving records temporarily using the Clipboard

The Clipboard gives you a place to collect records from one or several searches. The Clipboard will be lost after 8 hours of activity on the NLM Catalog or any of the other databases.

You may also save your search results indefinitely using My NCBI Collections.

To add records to the Clipboard:

1.

In your search results, use the check boxes to select records. To save all records do not click any check boxes.

2.

Use Send to, and select Clipboard.

3.

To view your selections, click the Clipboard portlet link.

To delete records from the Clipboard:

• Use the Remove from clipboard link to delete individual items, or use the check boxes to select items to delete, and then click the Remove selected items link.
• To delete all records from the Clipboard, do not select any items, click the Remove all link.

More information about the Clipboard:

• The Clipboard portlet displays the total number of items in the Clipboard.
• The maximum number of items that can be sent to the Clipboard is 500. If you select Clipboard from Send to without selecting citations, the system will add all (up to 500 citations) of your search results to the Clipboard.
• The Clipboard will not add a citation that is currently in the Clipboard; it will not create duplicate entries.
• The NLM Catalog uses cookies to add your selections to the Clipboard. For you to use this feature, your Web browser must be set to accept cookies.
• Records in the Clipboard are represented by the search number #0, which may be used in Boolean search statements. For example, to limit the records you have collected in the Clipboard to English language articles, use the following search: #0 AND english [la]. This does not affect or replace the Clipboard contents.

Saving records as a text file

1.

In your search results, use the check boxes to select records. You may move to other pages to continue your selections. If you do not make any selections, the NLM Catalog will save the entire retrieval.

2.

From Send to, select File.

3.

Your Web browser will prompt you to save the search results in a file on your computer.

More information about saving records to a file:

• Saving a large retrieval may take several minutes.
• The default for the Send to File feature is to save the entire retrieval unless you select specific records. For example, if you use the Send to File feature for results displaying 1 to 20 of 2,356, your saved file will contain all 2,356 records.
• To save records in HTML format, use the Save as... function of your browser. Change the file extension to html. When saving as HTML, only those records displayed on the page will be saved so you may want to consider changing the number of items per page.

E-mailing records

1.

In your search results, use the check boxes to select records. To e-mail all records displayed on the page, do not make any selections.

2.

From Send to, select E-mail.

3.

Choose selections for Format, Sort by, Number to send, and start from citation.

4.

Enter an e-mail address. You may also enter additional text that will be included in the e-mail.

5.

Click E-mail. The system returns you to your results page and displays a confirmation e-mail sent message.

Note: Use My NCBI to create an automatic e-mail update for searches.

Your NLM Catalog results will be sent from the NCBI automatic mail server with a "Subject" of NLM Catalog Search Results. Do not reply to this message. This is not a functioning customer service e-mail address.

More information about e-mailing records:

• You may e-mail up to 200 items at a time to a single e-mail address.
• The search will be included in your results email, or a notation indicating the number of selected items.

Searching for journals in the NLM Catalog

1.

Click on Journals in NCBI Databases on the home page of the NLM Catalog.

2.

Enter a topic, journal title or abbreviation, or ISSN into the search box. Automatic suggestions will display as you type your search terms.

3.

Click Search.

4.

On the summary display, click the journal title for a specific journal or select the Journal or Full displays from the Display Settings menu to view additional information. The Journal display includes fields of interest to those searching for information about the journals in the NLM Catalog, including indexing information. The Full display has been expanded to include all available fields where applicable.

Building a PubMed search for journals

1.

Run a search and use the check boxes to select journals.

2.

Click Add to search builder in the PubMed search builder portlet. PubMed search builder only retrieves citations for PubMed journals.

3.

To add additional journals, continue searching the database and adding the journals to the PubMed search builder using the Add to search builder feature, and then click Search PubMed.

More information about searching for journals in NLM Catalog:

• You can also visit the Limits page to limit a search to various journal subsets. The NLM Catalog will apply an AND Boolean operator when the Journals referenced in the NCBI databases limit is selected with a Journal Subset limit. A notice appears at the top of your search results indicating that limits have been activated.
• Click the NLM ID to link to NLM holdings information in Locator Plus.
• Search results are displayed in Publication Date (descending) order.

Abstract/Index Tags [itag]

Used to specify the publications or databases in which a title has been indexed and/or abstracted, and the status of the indexing if known.

Use the index feature on the Advanced Search page to identify searchable values for the indexing publications or databases. These values include but are not limited to:

• Abridged Index Medicus
• Hospital and Health Administration Index
• Hospital Literature Index
• Index Medicus
• Index to Audiovisual Serials in the Health Sciences
• Index to Dental Literature
• International Nursing Index
• MEDLINE
• NLM Gateway meeting abstracts
• OLDMEDLINE
• PubMed

The searchable values for indexing status are:

• Ceased-publication
• Continued-by-another-indexed-title
• Currently-indexed
• Currently-indexed-Title-changed
• Date-range-of-indexed-citations-unspecified
• Deselected

Acid Free

Some or all of the publication is printed on acid-free paper. Search as acidfree.

All Fields [all]

Includes all searchable NLM Catalog fields.

Author [au]

The format to search for an author is: last name followed by a space and up to the first two initials followed by a space and a suffix abbreviation, if applicable. Do not use punctuation. Initials and suffixes may be removed when searching. The NLM Catalog automatically truncates on an author's name to account for varying initials. To turn off the automatic truncation, enclose the author's name in double quotes and qualify with [au] in brackets.

Broad Subject Term(s) [st]

Subject terms are assigned by NLM to MEDLINE journals to describe the journal’s overall scope. All of these subject terms are valid MeSH headings. The complete list of subject terms is available.

Corporate/Conference Name [cn]

Identifies the corporate or conference name associated with an item. Corporate or conference names display exactly as they appear in the item. Browse the index to build a search, to verify the form of name and/or spelling, or consult the Authority Index.

Country of Publication [pl]

The item’s country of publication. Geographic regions are not directly searchable. In order to retrieve records for all countries in a region (e.g., North America) it is necessary to OR together the countries of interest.

Current Format Status [cfs]

Search for all journals in electronic-only format using: electronic only[cfs]

Current Indexing Status

Search for MEDLINE indexed journals using: currentlyindexed. For everything in the NLM Catalog that is not a MEDLINE-indexed journal, use: notcurrentlyindexed.

Current Subset

To search for an indexed journal subset, enter in the search box jsubset?, where ? represents the subset value.

Currently or Previously Indexed for MEDLINE

Search for journals currently or previously indexed for MEDLINE using: reportedmedline[All Fields]

Filter [sb]

You can view the available filters by browsing the index on the Advanced Search page. The following new filters have been created: Journals in the NCBI databases, Journals Currently Indexed in MEDLINE, PubMed Only Journals. For more information about changing filter preferences, please see the MyNCBI Help.

Full Author Name [fau]

The complete name of the author. The format is last name then a space and the full first name, a space and middle initial, if applicable.

Indexing Subset [xs]

Used for internal processing at NLM.

ISO Abbreviation [iso abbr]

The Internal Organization for Standardization (ISO) journal abbreviation.

ISSN [issn]

The journal’s ISSN number.

ISSN Type [is]

Search for all print, electronic, or linking ISSNs as:

• print[is]
• electronic[is]
• linking[is]

Item Type [item]

This field contains data related to the format of the material. It contains one of the following values:

• Book
• Book Chapter
• Collection manuscript
• Collection print
• Electronic Resource
• Electronic Serial
• Kit
• Manuscript
• Map
• Mixed Material
• Nonmusical Recording
• Printed Music
• Serial
• Still Image
• Three Dimensional Object
• Visual Material.

Journal [jo] and title abbreviation [ta]

Includes the journal title abbreviation or full journal title. If a journal title contains special characters, e.g., parentheses, brackets, enter the title without these characters.

You can also search for journals by their NLM Title Abbreviation using the title abbreviation [ta] tag.

Language [la]

The material’s language of publication.

The complete list of languages used is based on the official list of languages provided in the MARC Code List of Languages, a standard maintained by the U.S. Library of Congress.

To see the list of available languages, browse the index.

MESH Major Topic [majr]

A MeSH term that is one of the main topics discussed in an item denoted by an asterisk on the MeSH term or MeSH/Subheading combination.

MeSH Subheading [sh]

MeSH Subheadings are used with MeSH terms to help describe more completely a particular aspect of a subject. For example, the drug therapy of asthma is displayed as asthma/drug therapy. The MeSH Subheading field allows users to "free float." MeSH Subheadings automatically include the more specific Subheading terms under the term in a search. To turn off this automatic feature, use the search syntax [sh:noexp]. In addition, you can enter the MEDLINE two letter MeSH Subheading abbreviations rather than spelling out the Subheading.

MeSH Terms [mh]

Notes on MeSH Terms and Major MeSH Topic search fields:

• To search the term only as a MeSH term, qualify it using the search field tags, e.g., [mh] for MeSH Terms or [majr] for MeSH Major Topic. A qualified term is checked against the MeSH Translation table and mapped to the appropriate MeSH term. Some concepts may map to two or more MeSH terms. To turn off this mapping, enclose the MeSH term in double quotes and qualify with [mh], e.g., "cold" [mh].
• MeSH terms are arranged hierarchically by subject categories with more specific terms arranged beneath broader terms. MeSH terms in the NLM Catalog automatically include the more specific MeSH terms in a search.
• To turn off the automatic inclusion of the more specific terms, use the syntax [field:noexp], e.g., hypertension [mh:noexp], or hypertension [majr:noexp], or hypertension/therapy [mh:noexp]. The latter example turns off the more specific terms in both parts, searching for only the one Subheading therapy attached directly to only the one MeSH term hypertension.
• If parentheses are embedded in a MeSH term, replace the parentheses with a space and qualify with [mh].

NLM Unique ID [nlmid]

The NLM Integrated Library System alpha-numeric identifier for the item. You can also search the NLM Catalog for an NLM ID without the qualifier.

Olio [olio]

Includes: general note, NLM catalog record owner, abstract, contents note, and other abstract.

Other Number [other num]

Includes: ISBN, government document classification number, LCCN, other id, and report number.

Other Term [ot]

Includes: broad journal heading and other subject name.

Personal Full Name as Subject [fps]

Use this search field tag to limit retrieval to records in which the name is the subject of the title/material. Search using the full name; last name comma space and the first name.

Personal Name as Subject [ps]

Use this search field tag to limit retrieval to records in which the name is the subject of the title/material. Search names following the Author field format.

Publication Status [status]

Includes the status of a serial: open, closed, or unknown.

Publication Type [pt]

Describes the type of material the item represents. See the full list of publication types.

Publication Year [dp]

The year that the item was published. To enter a year range, insert a colon (:) between each year.

Publication End Year [eyr]

The last year of the publication. To enter a date range, insert a colon between each date, e.g., 1996:1998 [eyr]

Publication Start Year [syr]

The first year of the publication. To enter a date range, insert a colon between each date, e.g., 1996:1998 [syr]

Publisher [publ]

The name of the publisher.

PubMed Central Holdings

Search for journals currently in PubMed Central (PMC) as: journalspmc and for forthcoming PMC journals as: journalspmcforthcoming.

Resource Type [res type]

Describes the type of resource the item represents See the full list of resource types.

Table

Table 4 List of Resource Types

Series [ser]

Related items with an overall title for the group; they may be numbered.

Title [ti]

Words and numbers included in the title of an item. Do not use punctuation.

URL [url]

The Uniform Resource Locator (URL) or the Web address of a particular item. To search for URLs, the item must start with http:// and be enclosed in quotes. Also the URL must be the exact address of the item.

Version Indexed

Search for the version of the journal indexed as currentlyindexedprint or currentlyindexedelectronic.

What is the Authority Index?

• Provides access to an index of full author names (including dates and name qualifiers), organizations, conference names, and series titles, associated with the bibliographic records in the NLM Catalog.
• Offers added value by incorporating rich cross-reference entries for variant forms of names (includes personal, corporate or conference names) and titles that lead the user from a raw, initial search to the established form used on bibliographic records in the NLM Catalog.
• Supports searching of names that may have changed over time, providing links to other and historical names used by authors or organizations and to conference names and series titles that have changed numerous times. For series titles, additional information regarding NLM's bibliographic treatment of that series is also provided (see Display of Series Information below).

Using the Authority Index

Click on the Authority Index on the NLM Catalog home page. Enter the name (includes personal, corporate or conference names) or series title as an unqualified search in the search box and click Search.

Alternatively, use the Authority Information index on the Advanced Search page to find the exact name of a person, organization, conference, or series title. Then add the term(s) to the search box and run the search.

Results of a Search of the Authority Index

A search of the authority index results in an alphabetic display. The established form of the name is hyperlinked; clicking on this link retrieves the bibliographic record(s) associated with that name in the NLM Catalog.

Using Cross References in the Authority Index

The authority index also provides access to cross-reference entries for variant forms of names and titles that can assist the searcher in identifying the form used in NLM bibliographic records and improve the success and exactness of retrieval. Additionally, links are provided to the different forms of a name or series title that may have changed over time.

Display of Series Information

When a series title is searched in the authority index, the display of the series title is prefaced by a plus sign (+) and the label "Series: ," with the title of the series appearing alphabetically.

Clicking on the plus sign reveals additional information related to the NLM treatment of that series title. The information provided includes the NLM analysis practice, classification practice, and classification number (when present). These data appear labeled as:

Special Considerations

• New and changed authority information is added to the NLM Catalog on a weekly basis; therefore, the search results may not be comprehensive.