to height or hair color because those system labels are not as straightforward and
consistent as the alphabet is. The phone book is another example of a structure
for organizing information. The white pages are arranged in alphabetical order.
This is a very effective way to organize information when one knows the name
of the business one is seeking. The yellow pages offer another organizational
structure for searching. Subject listings in the yellow pages were created so
that if one knows the type of business, but not its name, the information can
be found. The key to using the yellow pages, though, is to know exactly what
terms the creators used for the subject areas. For example, if you need a haircut,
would you use “hair,” “barber,” or “beauty shop” as a keyword? Although this
example might seem very elementary right now, understanding how the phone
book is organized will be beneficial when considering the most common types
of electronic searches.
Structures can also be designed to organize physical objects. For example, in
bookstores, books are organized in subject areas around the store, and within
each area, they are perhaps grouped into subcategories and shelved by the author’s
last name. Libraries are arranged in the same manner, but, because there are
many more books to organize, a consistent number or letter/number combina-
tion system is used. Most public and school libraries use the Dewey decimal
system, while most academic libraries in the United States use the Library of
Congress system. Many health sciences libraries use the National Library of
Medicine system. Here too, when the books are in their general subject areas,
they are then categorized into smaller subcategories and shelved according to
the author’s last name. In the library system, every item has its own unique
call number according to its subject area and author’s last name. No other item
will have that same number. Familiarity with the system and knowing which
system the library uses make searching for sources more efficient.
Knowing general call numbers of a subject can also expedite searches for
items in a library collection. For example, in academic libraries using the Library
of Congress method, medical books are located within the R area shelves and
nursing books are on the RT shelves. Further knowledge of what subjects the
numbers connote can lead to more detailed browsing, such as knowing that
the nursing research texts’ section is RT 81.5, while writings about nursing
history are on the RT 31 shelves. Call numbers for specific books are easily
found through searching the library’s catalog.
Although the structure used in libraries is quite efficient for locating sources,
confusion can occur when sources can be classified in more than one way.
Information on a specific topic might be scattered throughout the collection. For
example, in a search for sources on the topic of ethical practices and how they relate
to health care, it is helpful to browse multiple areas, such as nursing ethics, medi-
cal philosophy, medical ethics, law of the United States, and medical legislation.
KEY TERM
call number: Unique
identification
number assigned to
items in a library by
subject and author
name4.3 How Sources Are Organized 105