Databases vary by the type and number of records they contain, their dates of coverage, the formats of literature they consider (i.e., books, articles, and/or multimedia items), and the scope (or subject area(s)) of the database.
When searching for animal research alternatives, it is very important to look in more than one database. While your first instinct may be to look only in PubMed, there are a wide variety of other options that will usually give you different but just as relevant results.
