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Overview of Digital Collections from the National Library of Medicine

Digital Collections is the National Library of Medicine's (NLM) free online archive of historical biomedical books and videos. All the content in Digital Collections is in the public domain and freely available worldwide. From the home page, search for books and videos by terms or phrases, narrow resources by selecting a “Refine by” category, or choose a collection from the rotating carousel. View books and videos using the Book Viewer and Video Player, which are accessible via the Resource page.


Enter search terms or phrases in the search box at the top of any page on the site. Your search is executed against the full-text and metadata fields of every resource in the repository. Only resources with terms matching your search term or phrase will be included in the search results. Click the title link or the thumbnail to view the resource's record page or narrow your results using the “Refine by” categories (see Figure 1).

A complete list of metadata fields is included in the Resource Records section. See Search Inside This Book and Searching Video Transcripts for how to search within an individual resource.

Search Results Display

The search results display includes a list of “Refine by” categories (see Figure 1A) to narrow the results, the terms, phrases and/or selected categories related to your search (see Figure 1B), a “Start Over” link to clear the current search (see Figure 1C), the total number of results (see Figure 1D), the display options for results per page, sorting options for relevancy and title (see Figure 1E), and the list of results sorted by relevancy (see Figure 1F). Each result includes the resource’s title, a thumbnail of the cover page or video still, as well as the authors, publication information, and subjects. Click the title link or the thumbnail to view the resource's record page.

Refining Search Results

Narrow your search results by selecting one or more categories listed in the “Refine by” column to the left of the results (see Figure 1A). Click one of the categories to view an expanded list of metadata fields in the category. The total number of resources with the same metadata field is listed in parenthesis.  Every time you select a new category, the search results narrow further to include only results matching the selected refinements and terms/phrases.

The “Refine by” categories include; collections, subjects, authors, titles, formats, languages, and date range. Each category includes up to 10 of the most common metadata fields for the category based on the current search results.

Each time you refine the search, the new category is displayed above the search results.  Click the “x” next to the category in the “Refine by” list or at the top the page to remove it from your search.

Changing the Display

Use the drop-down menus above the first result to change the number of results per page or the sort order. Ten results are displayed by default. Change the number of results per page to 20, 50, or 100 based on your preference (see Figure 1D).

Sort results by relevance or title. Results are displayed in order of relevance by default. Select sort by title to view an “A” to “Z” list of titles. Titles beginning with quotations may appear before the titles beginning with “A” (see Figure 1D).

The Digital Collections basic search feature determines search result relevancy using a weighted search algorithm. The algorithm searches the metadata fields and the full text of all resources and ranks your search results according to where the term or phrase appears in the Title, Author, Subject, Full Text, and Description.

Search Results Display

Figure 1: Search Results Display for the phrase "Asiatic cholera." The "Refine by" categories are displayed in the left column (A), the search results statement includes the term or phrase you searched for (B), a "Start Over" link to clear the search terms (C), the total number of results and navigationt results on the previous and next page (D), display options for the number of results per page is automatically set to 10 and sorted by relevance (E), and the search results (F).

Navigating Between Results

Navigate between results on the search results page (see Figure 1D) or the resource record page (see Figure 2A). Select “Next” or “Previous” to view the list of results on the search results page or the next or previous resource record in the results.

Starting a New Search

Click “Start Over” on the search results display or resource record page to clear the current search terms and refinements (see Figure 1C or Figure 2B). Otherwise, the selected refinements will be applied to the new search results. The current search terms, phrases, and refinements are listed after “You searched for” above the results.

Resource Records

The "Resource Record" page includes the resource's metadata information and a link to the Book Viewer (Figure 2) or the Video Player. The resource metadata fields include; titles, authors, publication date, publication information, languages, format, subjects, geographic subjects, rights, identifiers, and description.

Open the resource by selecting the "View Book" or "View Video" links to view the resource in the Book Viewer or the Video Player (see Figure 2F). Click the linked authors or subjects to search for other resources with similar metadata (see Figure 2C and D).

Select the "See catalog record…" link in the "Identifier" field to view the resource's bibliographic record in LocatorPlus, NLM's online catalog (see Figure 2E).

Page through the search results via the resource record pages by selecting the “Next” or “Previous” links (see Figure 2A). Select the “Back to Search” link to return the search results display (see Figure 2B). Start a new search by selecting “Start Over” and entering a new search term or phrase in the search box on the Home page.

Resource Record

Figure 2: Resource Record. Navigate between individual search results by selecting "Previous" or "Next" (A). Click "Back to Search" to return to the search results page or "Start Over" to clear your search terms and refinements (B). Select the "Authors" and "Subject" links to view related resources (C and D). The identifiers includes links to the catalog record and the permanent URL (E). Select "View Book" to open the resource in the book viewer (F).

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