Notes from Newman: HNFE Research & Resources: Expert Research Tip: Using DOIs, PMIDs, and Other Unique Identifiers

When I first started working in libraries (in 1999), a DOI was virtually unheard of. When I first started working in academic and research libraries (in 2003), DOIs had only been around for 3 years, so a considerable amount of confusion still surrounded the concept. Now, in 2011, I think the most people have a pretty good idea what a DOI does, and how it can be useful. Even so, I still get questions about using DOIs, PMIDs, and other unique identifiers that can help you locate literature quickly and easily, especially if you are using EndNote, Zotero, or another bibliographic manager. My expert research tip for today is:

Pay attention to unique identifiers on books and articles, and use them to save time as you organize your resources and research.

A bit of background on the four types of identifiers I will discuss: ISBNs, ISSNs, DOIs, and PMID--

ISBN: International Standard Book Number. Example: 978-0060852566

The idea of the ISBN was first established in 1966; since 2007, all books are required to have a 13-digit number, which is why you will see books have a 10-digit and an 13-digit ISBN. You can use the ISBN import book information into Zotero, and to find books if you are using LibX. Finally, you can also search Addison, the catalog, for a book using its ISBN--you can simply drop down the main drop-down search box on the library home page (www.lib.vt.edu), select ISBN, and search that way.

ISSN: International Standard Serial Number. Example: 00987484

The ISSN is the unique identifier for a journal. You won't be able to find specific articles with this number--use DOIs or PMIDs for that--but you will be able to locate the journal itself that way. For example, you would use this if you were checking Addison to find our subscription information for a particular journal. The instructions I wrote for the ISBN (above) in Addison also work for using the ISSN in Addison.

DOI: Digital Object Identifier. Example: 10.1186/1475-2875-9-284

I've often heard other librarians refer to a DOI as a social security number for a journal article. A DOI will permanently link you to a particular article, regardless of the database that you find it in! This is great, since publishers will often redesign their websites, making previous links to articles unusable. You can even create a stable link to a journal article by turning the DOI into a URL. The formula for creating a URL from a DOI is: http://dx.doi.org/DOI

PMID: PubMed Identifier. Example: 21298748

The PMID will link you directly to the PubMed record for a particular article; the PMID will be found at the very bottom of an article's PubMed record. You can go to PubMed, and use this number in the basic search box. Remember, though, to sign in through Off Campus Sign In if you want to use Get VText to find the full text of the article you're locating.

Basically, these numbers can really help you while you are conducting research in a database, or even in a commercial bookseller, like Amazon. All books will have an ISSN, which can be a quick way for you to store or remember a particular book. The same strategy works for articles that you find in PubMed--all articles will have a PMID. Instead of jotting down the entire citation, you can jot down the PMID, and then simply type in that PMID when you need to access the PubMed record for that article again. In other databases, look for the DOI--it will work the same way.

If you are using a bibliographic manager--EndNote and Zotero are the most popular--then you can use these numbers to help you locate, and in some cases, easily import new references. Images below show Zotero, on top, and EndNote, on the bottom: