dren may show anger or occasionally aggres sion toward someone who is forcing separa-
tion. When alone, especially in  the evening or the dark, youn g children may report unusual
perceptual experiences (e.g., seeing people p eering into their room, frightening creatures
reaching for them, feeling eyes staring at them ). Children with this disorder may be de-
scribed as demanding, intrusive, and in need of constant attention, and, as adults, may ap-
pear dependent and overprotective. The indi vidual’s excessive de mands often become a
source of frustration fo r family members, leading to resent ment and conflict in the family.
Prevalence
The 12-month prevalence of separation anxiety disorder among adults in the United States
is 0.9%–1.9%. In children, 6- to  12-month prevalence is estima ted to be approximately 4%.
In adolescents in the United States, the 12-mo nth prevalence is 1.6%. Separation anxiety
disorder decreases in prevalence from child hood through adolescence and adulthood and
is the most prevalent anxiety diso rder in children younger than 12 years. In clinical sam-
ples of children, the disorder is equally common in males and females. In the community,
the disorder is more frequent in females.
Development and Course
Periods of heightened separation anxiety from attachment figures are part of normal early
development and may indicate the development of secure attachment relationships (e.g.,
around 1 year of age, when infants may suffe r from stranger anxiety). Onset of separation
anxiety disorder may be as early as preschoo l age and may occur at any time during child-
hood and more rarely in adolescence. Typica lly there are periods of  exacerbation and re-