The difference between social phobia and social anxiety disorder (SAD) is largely chronological, in that social phobia is the former term and SAD is the current term for the disorder. The official psychiatric diagnosis of social phobia was introduced in the third edition of the Diagnostic and Statistical Manual (DSM-III). Social phobia was described as a fear of performance situations, and did not include fears of less formal situations such as casual conversations.
In 1994, with the release of the DSM-IV, the term social anxiety disorder (SAD) replaced social phobia. The new term was used to describe how broad and generalized fears are a part of the disorder. The disorder was defined as a "marked and persistent fear of one or more social or performance situations in which the person is exposed to unfamiliar people or possible scrutiny by others."
The terms social phobia and SAD are often used interchangeably in current literature to refer to SAD.
Sources:
Weiner IB, Freeheim DK. Handbook of psychology. New York: John Wiley & Sons; 2004.
Furmark T. Social phobia: From epidemiology to brain function [dissertation]. Uppsala, Sweden: Department of Psychology, Uppsala University; 2000.
