Multiple Ways to Search An Online Catalog of Electronic Theses and Dissertations

[tweetmeme source=”Intellogist” only_single=false] Free catalogs of non-patent literature (NPL) that cover the collections of multiple academic institutions can provide a valuable central search portal when a user is searching for a particular type of NPL.  For example, the OCLC WorldCat system allows users to search for print and media resources in thousands of library catalogs simultaneously. If you want to search for electronic resources, specifically electronically published theses and dissertations, then the Networked Digital Library of Theses and Dissertations (NDLTD) is an excellent central portal where you can begin your search.  Through two different search options provided by NDLTD, users can search an expansive catalog of electronic theses and dissertations submitted by a wide variety of academic and research institutions.

Technology may be discussed in theses and dissertations that isn’t patented, but it is still available in the public domain and therefore qualifies as relevant prior art.  During validity searches when professional patent searchers scour the earth for all available prior art, searching a central portal that accesses many websites simultaneously which host a particular type of NPL is a very useful search strategy.

After the jump, we’ll take a closer look at the purpose of the NDLTD website and options for searching its Union Catalog of electronic theses and dissertations.

What is the NDLTD?

The Networked Digital Library of Theses and Dissertations (NDLTD) is a website created by an organization of the same name that promotes “the adoption, creation, use, dissemination and preservation of electronic theses and dissertations.” The website includes options for users to find, submit, and manage electronic theses and dissertations (ETDs). Under the section of the website to “Find ETDs,” the user can access a variety of tools to search the NDLTD Union Catalog. The site describes the NDLTD Union Catalog as:

A collaborative effort of the NDLTD, OCLC, VTLS, and Scirus, the NDLTD Union Catalog contains more than one million records of electronic theses and dissertations. For students and researchers, the Union Catalog makes individual collections of NDLTD member institutions and consortia appear as one seamless digital library of ETDs.

The “Find” section of the site provides links to two tools to search the NDLTD Union Catalog (described in detail below), as well as a list of additional useful ETD search tools (like ADT (Australiasian Digital Theses Program) and DART-Europe E-theses Portal).

Search Option 1: Scirus ETD Search

Scirus ETD Search “is provided courtesy of Scirus, based on data harvested from the Union Archive hosted by OCLC.” The tool includes a basic search option (a simple keyword search form) and an advanced search form, which allows users to search for “all of these words,” “any of these words,” or “exact phrase” within specific fields (selected via drop-down menu). In the advanced search, the user can combine up to three text boxes (each corresponding with a selected field) with Boolean operators. Under the advanced search form, users can also limit results based on a publication date range (selected via drop-down menu) and subject matter (by selecting desired subjects via check box). Finally, users can select to search within the collection of ETDs or within the Scholarly Web collection (which appears to be all content indexed by the Scirus search engine).

The quick and advanced search forms of the Scirus ETD Search.

10 results are displayed per page, and result include the title, author, publication date, and an excerpt with query keywords bolded. Users can sort results by relevance or date, and they may also choose to refine the results using a list of relevant keywords.

The results page for the Scirus ETD Search tool.

Select a result title to view the full document record on the website of the institution where the document was originally published.

The full record for a document is displayed on the original institution’s website.

Search Option 2: VTLS Visualizer

The VTLS Visualizer also includes both a quick keyword search form and a fielded advanced search form, which allows users to enter text in up to four forms corresponding to a selected field (selected via drop-down menu) that contains “all of these words,” “exact phrase,” “at least one of these words,” or “none of these words.” Under the advanced search option, the user can also filter the query by language and document format. Results can be sorted by a range of criteria (relevance, recently added items first, title, author, publishing date, call number, or creation date).

The quick and advanced search forms for the VTLS Visualizer.

Results are displayed 30 to a page and include the title, author, and a link to the source record on the website of an outside institution (the full record opens in a new window). On the results, page, users can further refine the search through a side menu by addition additional terms or filtering results by “set,” language, format, publication year, author, or subject. Above the results list, users can also delete specific search terms from the query, or turn the query into an RSS feed.

The search results page for the VTLS Visualizer.

Finally, users can select results via check box to add to a cart. Under the “cart” section, users may email or export the list of selected documents (in CSV or EndNote format), and users who are registered through the portal can request or save selected items in the “cart” section.


Users can search the NDLTD Union Catalog through two different search forms that each offer unique benefits and drawbacks. The Scirus ETD Search allows users to filter directly from the advanced search form by publication date range and subject matter, while the advanced search form of the VTLS Visualizer can filter by language or format.  The filtering options from the results page are more sophisticated on the VTLS Visualizer, which allows users to add additional terms to the query or filter by a wide variety of criteria.  The VTLS Visualizer also allows more sorting options for the results than the Scirus ETD Search results page.  The Scirus ETD Search gives users the option to search the entire Scirus index, and the VTLS Visualizer has the added benefits of the option to save/email/export selected results and the feature turns a query into an RSS feed. Since both tools search the same catalog, users can benefit by utilizing the unique filtering options in both portals to refine their search and perhaps locate new relevant resources.

Do you know of any other portals for searching multiple collections of theses and dissertations simultaneously?  Let us know in the comments!

Patent Searches from Landon IP

This post was contributed by Joelle Mornini. The Intellogist blog is provided for free by Intellogist’s parent company Landon IP, a major provider of patent searches, trademark searches, technical translations, and information retrieval services.


3 Responses

  1. Thanks, very much. Is a very interesting article for me because I´m preparing classes for university history students on “research, the web and social medias: methodology and searching”.
    Ximena Cruzat;

  2. […] Multiple Ways to Search An Online Catalog of Electronic Theses and Dissertations (The Intellogist Blog) […]

  3. Hello very cool site!! Man .. Beautiful .. Wonderful .. I’ll bookmark your site and take the feeds additionally? I am glad to find numerous useful info right here within the submit, we want develop extra techniques in this regard, thank you for sharing. . . . . .

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: