In order to select a source, you need to know a few things about it:

● Cover:

• subjects covered
• dates, languages,
• types of documents (bibliographic elements, articles, patents, pictures, digital data, …)

● Information delivered:

Bibliographic reference, abstract or full text for the whole database.

Access to full text on part of the database: Moving wall or embargo on archives or conversely, partial subscription for the most recent numbers.

● Conditions for access:

• free access online / University memberships and access restricted to university space / University membership and remote access with password.
• immediate access to bibliographic elements and access to full text via a link resolver and in accordance with memberships at your university.

Base de données (Database), 2008, Stéphane Pouyllau. Licence CC BY-NC-SA. Source: Flickr

Not all sources offer the same ranking options.

These options depend on the method used for indexing the documents, on available operators and possible restrictions.

The best ones rank results for a request by review, by author, by laboratory, by topic and thus offer a chance to multiply, in a few clicks, the perspectives on a topic (see the restrictions tab).

The quality of the information delivered by a source is the result of an editing process which you need to either be familiar with or imagine.

Does the selected source of information propose heterogeneous pages, academic website pages, scientific articles, selected and ranked review articles, with a high profile advisory board?

The most sophisticated databases offer watch services for identified users (for instance:  monitoring Ebsco databases via RSS feed), they also allow saving the results of a search, edit or export of a bibliography or of annotations.