Background. There is a lack of current detailed national data on the prevalence, correlates, disability and co-morbidity of DSM-IV specific phobia (SP), the prevalence of specific objects and situations feared, and associations between impairment, treatment and co-morbidity and the number of specific situations and objects feared, among adults in the USA.

Method. The data were derived from a large (43093) representative sample of the adult population in the USA.

Results. Prevalences of 12-month and lifetime DSM-IV SP were 7·1% and 9·4% respectively. Being female, young, and low income increased risk, while being Asian or Hispanic decreased risk (p<0·05). The mean age at onset of SP was 9·7 years, the mean duration of episode was 20·1 years and only 8·0% reported treatment specifically for SP. Most specific phobias involved multiple fears, and an increasing number of fears, regardless of content, was associated with greater disability and impairment, treatment seeking and co-morbidity with other Axis I and II disorders.

Conclusions. SP is a highly prevalent, disabling and co-morbid disorder in the US adult population. The early onset of SP and the disorders most strongly associated with it highlights the need for longitudinal studies beginning in early childhood. Results suggest the existence of a generalized subtype of SP much like social phobia, which, once revealed, may lead to a classification of SP that is more etiologically and therapeutically meaningful.