“Anxiety disorder” is a blanket term covering several different forms of abnormal and pathological fear and anxiety which only came under the aegis of psychiatry at the very end of the 19th century. Gelder, Mayou & Geddes (2005) explains that anxiety disorders are classified in two groups: continuous symptoms and episodic symptoms. Current psychiatric diagnostic criteria recognize a wide variety of anxiety disorders. Recent surveys have found that as many as 18% of Americans may be affected by one or more of them, including:
Generalized anxiety disorder
Panic disorder with agoraphobia
Social anxiety disorder
Post-traumatic stress disorder
Childhood anxiety disorders
The term “anxiety” covers four aspects of experiences an individual may have: mental apprehension, physical tension, physical symptoms and dissociative anxiety (symptoms associated with hyperventilation). Anxiety disorder is divided into generalized anxiety, phobic, and panic disorders; each has its own characteristics and symptoms and they require different treatment (Gelder et al. 2005). The emotions present in anxiety disorders range from simple nervousness to bouts of terror (Barker 2003).
Standardized screening clinical questionnaires such as Zung Self-Rating Anxiety Scale can be used to detect anxiety symptoms, and suggest the need for a formal diagnostic assessment of anxiety disorder.