Index terms are controlled vocabulary terms used in database records to make searching easier and more successful. By standardizing the words or phrases used to represent concepts, you don't need to try and figure out all the ways different authors could refer to the same concept.
Most reference resources are considered "tertiary" souce materials. These books and websites provide background information and an overview and analysis of a subject or concept.
Tertiary souirces have been compiled from secondary sources. Unlike a secondary source book or journal article, tertiary sources are not intended to be read in their entirety. Instead, they are most often used to clarify terms and concepts about a particular topic.Tertiary sources include
*Also considered secondary
The American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM) is a classification of mental disorders with associated criteria designed to facilitate more reliable diagnoses of these disorders. Since a complete description of the underlying pathological processes is not possible for most mental disorders, it is important to emphasize that the current diagnostic criteria are the best available description of how mental disorders are expressed and can be recognized by trained clinicians. DSM is intended to serve as a practical, functional, and flexible guide for organizing information that can aid in the accurate diagnosis and treatment of mental disorders. It is a tool for clinicians, an essential educational resource for students and practitioners, and a reference for researchers in the field.
The Merck Manuals have been standard medical reference sources for over 100 years providing detailed information on virtually all disorders, complete with discussion of symptoms and current therapy.
The publisher provides free access to some Merck Manuals: