Frequency Information on the frequency of<unk>  in the West is limited, in part due to the complexities of the diagnostic process. In neurology clinics, the reported prevalence of unexplained symptoms among new patients is very high (between 30 and 60%). However, diagnosis of<unk>  typically requires an additional psychiatric evaluation, and since few patients will see a psychiatrist it is unclear what proportion of the unexplained symptoms are actually due to<unk> . Large scale psychiatric registers in the US and Iceland found incidence rates of 22 and 11 newly diagnosed cases per 100,000 person-years, respectively. Some estimates claim that in the general population, between 0.011% and 0.5% of the population have<unk> . Culture Although it is often thought that the frequency of<unk>  may be higher outside of the West, perhaps in relation to cultural and medical attitudes, evidence of this is limited. A community survey of urban Turkey found a prevalence of 5.6%. Many authors have found occurrence of<unk>  to be more frequent in rural, lower socio-economic groups, where technological investigation of patients is limited and people may know less about medical and psychological concepts. Gender Historically, the concept of 'hysteria' was originally understood to be a condition exclusively affecting women, though the concept was eventually extended to men. In recent surveys of<unk>  (formerly classified as "hysterical neurosis,<unk>  type"), females predominate, with between two and six female patients for every male but some research suggests this gender disparity may be confounded by higher rates of violence against women. Age<unk>  may present at any age but is rare in children younger than ten or in the elderly. Studies suggest a peak onset in the mid-to-late 30s.
Conversion disorder
Somatization disorder
Otodental syndrome
Malingering
Bruxism
Anterior cerebral artery syndrome
Perisylvian syndrome
Diencephalic syndrome