"Scope" is a term sometimes used to describe the type of information in a database.
It will help you understand what type of material is available for retrieval. If an item is out of the scope of a database, it might exist, but will never be found in that database.
Some common types of scope in bibliographic databases are:
Look for an "About the database" or "Scope" link on a database site if you have questions about what you can expect to find.
Besides scope, it is useful to know what fields a database record contains and which of those fields are searchable.
Example:
If you want to find a doctor in your town who can tell you if you have allergies, you need to know that the record contains "medical field" or "area of specialty" along with location information. You would also need to know that these fields are searchable.
The illustration below from the AMA Doctor Finder database shows one of the search screens (by physician specialty). In this database, city, state, zip code, medical specialty and physician name are all searchable fields.
Subject headings are a form of "controlled vocabulary." Database creators can define which subject terms are acceptable and assign only those terms as subject headings for each record. The resulting list of terms is often referred to as a thesaurus. When done thoroughly, a thesaurus will not only list acceptable subject headings, but will also indicate related terms, broader terms and narrower terms for a concept.
The illustration below shows a sample thesaurus entry from the fee-based MEDLINE database. In this example you will see a definition of the term, broader terms (those with the + in front of them), and related terms. MEDLINE is known for its complex and thorough thesaurus structure.
Subject heading searching can be much more precise than keyword searching, as you are sure to retrieve only your intended concept. It will keep you from retrieving items with the same term, but meaning something different (i.e., AIDS -- the disease vs. aids -- assisting devices).
Generally a combination of keyword and subject heading searching will lead the researcher to the most complete and targeted results. This search strategy is described in more detail on the next page of this tutorial.
Look at the Overview to determine the scope of information contained in: Built in America
Could you use this database to find photographs of Fallingwater, a historic American house built by Frank Lloyd Wright in 1937?
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